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Here at National Geographic Kids, we love wonderful wild bears! Join us as we learn about one of nature's cutest critters in our facts about pandas!
Facts about pandas

1. Giant pandas (often referred to as simply "pandas") are black and white bears. In the wild, they are found in thick bamboo forests, high up in the mountains of central China - you can check out our cool facts about China, here!

2. These magnificent mammals are omnivores. But whilst pandas will occasionally eat small animals and fish, bamboo counts for 99 percent of their diet.

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3. Pandas are BIG eaters - every day they fill their tummies for up to 12 hours, shifting up to 12 kilograms of bamboo!

4. The giant panda's scientific name is Ailuropoda melanoleuca, which means "black and white cat-foot".

5. Giant pandas grow to between 1.2m and 1.5m, and weigh between 75kg and 135kg. Scientists aren't sure how long pandas live in the wild, but in captivity they live to be around 30 years old.

6. Baby pandas are born pink and measure about 15cm - that's about the size of a pencil! They are also born blind and only open their eyes six to eight weeks after birth.

7. It's thought that these magnificent mammals are solitary animals, with males and females only coming together briefly to mate. Recent research, however, suggests that giant pandas occasionally meet outside of breeding season, and communicate with each other through scent marks and calls.

Did you know that we have a FREE downloadable panda primary resource? Great for teachers, homeschoolers and parents alike!

8. Family time! Female pandas give birth to one or two cubs every two years. Cubs stay with their mothers for 18 months before venturing off on their own!

9. Unlike most other bears, pandas do not hibernate. When winter approaches, they head lower down their mountain homes to warmer temperatures, where they continue to chomp away on bamboo!

10. Excitingly, conservation efforts mean that panda bear numbers are increasing in the wild. Though there's still lots of work to be done, the species is no longer considered endangered. Hooray!

Love reading about brilliant bears? Then check out our ten black bear facts, here!

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10 facts about pandas! - National Geographic Kids

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Check out ten facts about pandas here at National Geographic Kids. Learn where pandas live, what they eat, how big they grow and much more!

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Bears - Discover Kodiak - Kodiak Island, Alaska

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Bears and humans have coexisted on the Kodiak Archipelago for almost 8,000 years. Ancestors of the Alutiiq people venerated and respected their island co-habitants and although they were hunted for food, clothing and tools, native hunters left the head in the field as a sign of respect to the spirit of the bears.

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ABC Nightline - Featuring Hercules the Liger

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Lions, Tigers and Ligers! | World's Weirdest

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Bears are highly evolved social animals with intelligence comparable to that of the great apes. Bears often share friendship, resources and security.

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Behavior

Contunico © ZDF Enterprises GmbH, Mainz

© Galyna Andrushko/Fotolia

The diet of bears is varied and flexible: most kinds eat just about anything. Bears that live near campsites or dumps do not even mind swallowing inedible things along with their food. Most species are especially fond of ants and honey. Bears also eat seeds, roots, nuts, berries, insects, rodents, fishes, deer, pigs, and lambs. Some brown bears fish for salmon, and the polar bear feeds almost exclusively on seals. The spectacled bear, on...

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bear - Behavior - The diet of bears is varied and flexible: most kinds eat just about anything. Bears that live near campsites or dumps do not even mind swallowing inedible things along with their food. Most species are especially fond of ants and honey.

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Why are sloths slow? And six other sloth facts

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Sloths—the adorable and lethargic animals living in treetops—depend on the health and survival of Central and South American tropical forests. Take a look at some common questions about sloths.

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The scientific answer to 'Why do living things have to die?'

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The scientific answer to 'Why do living things have to die?'

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Why do living things die?: originally appeared on Quora: The best answer to any question. Ask a question, get a great answer. Learn from experts and access insider knowledge. You can follow Quora on Twitter, Facebook, and Google+. Answer by Paul King, Computational Neuroscientist

CC-BY-SA-3.0/Matt H. Wade at Wikipedia

It's not that living things die; it's that multicellular organisms die. But why?

Every single-celled organism alive today has been in existence since life began over 3 billion years ago. This is because individual cells do not give birth, they divide. After cell division, the two cells that result are each as old as the single cell that preceded them. The cell does not become younger by dividing. (Although this may not be exactly true, see: [1])

Thus every cell in your body is over 3 billion years old.

The strategy that multicellular organisms such as humans use to project themselves into the future is to create new cell colonies from a single undifferentiated cell rather than maintaining existing colonies indefinitely. The main reason is that reproduction is more flexible and robust than maintenance, and it provides a way of starting over with a "clean slate" and slightly different genes. Complex organisms accumulate billions of errors and problems over their lifetime. Most of these errors are fixed as fast as they happen, but life takes a toll and not all problems are reversible. Just as reinstalling Microsoft Windows every so often fixes accumulated system issues, so does generating a new organism every so often from a single cell.

Given that biology has selected this strategy, evolution has optimized for producing the most successful offspring. Once the individual has reproduced, its only evolutionary role is to support the success of its offspring. Aging longer is just not something evolution has had a reason to optimize. And in fact given limited environmental resources, the offspring often do better if the older generation doesn't stay around forever competing with younger generations for scarce resources.

In terms of what happens physiologically, there are two main contributors to aging.

The first is the accumulation of biological defects. Viruses and disease take a toll even after healing; UV rays slowly but inevitably damage DNA; and proteins, cell structure, and the neurons which hold memories all degrade over time due to thermodynamic molecular disruptions and invasions by other species.

The second is the aging process itself. The organism develops to maturity and ages in stages according to a genetically determined life plan. Muscles atrophy, bones brittle, and metabolism changes. But the life plan has never run more than 80 years until recently, and evolution only ever optimized the first 40 years or so. So humans are in new territory that is poorly understood, and which evolution has never had a reason to fine tune.

It may be possible to slow or stop some of the genetically determined aging processes. While this may not be good for an overpopulated planet, it is sure to be popular with those that can afford the medical intervention. Let's just hope the social security system holds out!

[1] There is evidence that even in "symmetric" cell division, one child cell may be slightly "younger" (less prone to death) than the other. See: Stewert EJ, et al (2005). Aging and death in an organism that reproduces by morphologically symmetric division. PLoS Biology.

More questions on Quora:

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What Is the Scientific Answer to "Why Do Living Things Die?"

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Why do living things die?: originally appeared on Quora: The best answer to any question. Ask a question, get a great answer. Learn from experts and access insider knowledge. You can follow Quora on Twitter, Facebook, and Google+. Answer by Paul King, Computational Neuroscientist CC-BY-SA-3.0/Matt H.

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Fun Rabbit Facts for Kids - Interesting Information about Rabbits

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Check out our fun rabbit facts for kids. Learn about rabbit ears, where they live, what a young rabbit is called and much more.

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Surprisingly, Arctic Foxes are omnivores. They feed on lemmings, voles, Arctic Hares, birds and their eggs, and carrion. A famiy of Arctic Foxes can eat dozens of lemmings every day! Fish under the surface of ice are also part of their diet.

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The arctic fox is an incredibly hardy animal that can survive frigid Arctic temperatures as low as -58°F in the treeless lands where it makes its home. It has furry soles, short ears, and a short muzzle-all-important adaptations to the chilly clime. Arctic foxes live in burrows, and in a blizzard they may tunnel into the snow to create shelter.

Arctic foxes have beautiful white (sometimes blue-gray) coats that act as very effective winter camouflage. The natural hues allow the animal to blend into the tundra's ubiquitous snow and ice. When the seasons change, the fox's coat turns as well, adopting a brown or gray appearance that provides cover among the summer tundra's rocks and plants.

These colorings help foxes to effectively hunt rodents, birds, and even fish. But in winter prey can be scarce on the ground. At such times, arctic foxes will follow the region's premier predator-a polar bear-to eat the leftover scraps from its kills. Foxes will also eat vegetables when they are available.

Like a cat's, this fox's thick tail aids its balance. But for an arctic fox the tail (or "brush") is especially useful as warm cover in cold weather.

Female arctic foxes give birth each spring to a large litter of up to 14 pups.

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The arctic fox is an incredibly hardy animal that can survive frigid Arctic temperatures as low as -58°F in the treeless lands where it makes its home. It has furry soles, short ears, and a short muzzle-all-important adaptations to the chilly clime.

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Mix a zebra and a horse, and you get a zorse. Swap the horse for a donkey, and you have yourself a zonkey. When a pony and a zebra love each other very much, you wind up with a zoni.

It's fun to think of animal hybrids as the Reese's peanut butter cups of nature. You take a little of this and mix it with a little of that, and voilà -you get an end product more interesting (and delicious?) than the creatures you started with. But hybridization has its costs.

Zebroids-the name for any zebra-based hybrid-are almost always infertile, and they sometimes suffer from dwarfism. Perhaps this isn't so surprising. While horses, zebras, and donkeys look similar and belong to the same genus ( Equus), each species has a different number of chromosomes. So just because you can interbreed them doesn't mean you should.

And that Ian Malcolm-ian sentiment resonates across the world of hybrids. Take ligers, the chimera created by a lion and a tiger, popularized at least in part by a cameo in the not-quite-cult-classic Napoleon Dynamite. Whereas zebroids can run small, ligers suffer from unsustainable growth.

"Their hearts give out," says Susan Bass, director of public relations for Big Cat Rescue, the largest accredited big cat sanctuary in the world. "Their organs literally can't handle the weight."

Big Cat Rescue has cared for numerous hybrids over the years, including a liger that has since died. Bass says any hybridization between big cat species is irresponsible breeding at its worst, a deed done only for greed and with absolutely no conservation value.

"They are bred for lives in a cage. They're never going to be released into the wild. There is no wild for these cats," she says.

The liger is only one such concoction, by the way. There are also tigons, which is a cross between a female lion and a male tiger. (Ligers are technically the opposite.) Then you have leopons (leopard plus lion), jaguleps (jaguar plus leopard), and savannah cats (domestic cat plus serval). Or you can smush a female liger with a male lion and get a liliger. Same goes for mating a female tigon with a male ligon, the offspring of which is called a litigon. Tiligers, titigons. And on.

Basically, if you put a couple of kitties together for long enough, something will pop out, and people will shell out cash to see it. And, according to Bass, it'll probably have birth defects, die young, or end up in a rescue organization like Big Cat Rescue.

But big cats aren't the only cash cows. In the Middle East, the money mammal is the camel.

Camel racing and camel beauty pageantry-seriously, it's a thing-are now fueling an interest in more controlled and more effective camel breeding. Camel milk is also an up-and-coming industry, with some bottles already available for purchase in the United States.

But it's safe to say that if you've heard of the Camel Reproduction Centre in Dubai, it's probably not for any of the aforementioned reasons. No, you know them for the cama. The cama is a hybrid made from a camel and a llama. Because at this point, well, why the hell not?

Camas are sort of like llamas that have nibbled Eat Me cake. They're bigger than normal llamas but not quite as sizable as camels. They lack humps, but they do seem to have a thicker bone structure than llamas. Their other features also split the difference between the parents. Camels have short ears, llamas have long ones, and camas' are medium-size. Camels have round feet, llamas' are cloven, and the cama's again lie halfway between. The coat is long-haired and llama-y while the tail is more camelicious-which is also the name of a popular camel milk brand, FYI.

Lulu Skidmore, the scientific director of the CRC, says her team has managed to breed six camas so far, though all have been infertile. So why bother trying to make the cama happen? "If you get the best of both breeds you would have an animal that is bigger than a llama, but a more manageable size than a camel," says Skidmore. It would also have a good quality coat like the llama, and "because it is bigger there would be more of it."

I don't know-seems like a lot of work for a little extra wool.

It is possible, of course, for hybrids to occur without human intervention. For instance, the coyotes that have spread across the eastern U.S. over the past 70 years actually have a hefty helping of wolf and domestic dog genes. Africanized or "killer bees" were created by humans but persist in the wild. Marine iguanas have lain with land iguanas, there's been hanky-panky between hooded seals and harp seals, saltwater crocodiles have gotten busy with Siamese crocs, and six types of gulls have been known to dabble in extra-species sexcapades.

"Love is blind," jokes Andrew Derocher when I called him to confirm the existence of pizzlies-a hybrid between polar bears and brown bears, or grizzlies.

Derocher is a polar bear expert and professor at the University of Alberta. He says he's seen a handful of the hybrids in person but that there's evidence the crossover has been happening on and off for thousands of years. How, exactly, do a polar bear and brown bear join reproductive forces? Derocher isn't sure. It's likely, though, that the pair is a result of a male grizzly and a female polar bear. For one, the sizing would match up a little better-polar bears are larger than grizzlies, and males of both species are larger than females, so a male grizzly and a female polar bear wouldn't look all that awkward in a prom photo.

And two, grizzlies are epic bullies.

"At bowhead whale carcasses, where grizzly bear and polar bear territories overlap, you'll see the grizzlies basically dominate the carcass," says Derocher. "They push polar bears around like crazy." Does that mean male grizzlies might also actively out-compete male polar bears for mates? We don't know. Perhaps we'll find out if such hybridization becomes more common with the onset of climate change, as some project.

Actually, there's a good chance you're a bit of a hybrid yourself. Scientists now think our ancestors nookied around with Neanderthals some 30,000 years ago, and some of us retain portions of their DNA as a result. In other words, if you're of European or Asian descent, up to 4 percent of your DNA may come from another species.

All we need now is an annoying portmanteau to go with it. Say it with me now:

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Mix a zebra and a horse, and you get a zorse. Swap the horse for a donkey, and you have yourself a zonkey. When a pony and a zebra love each other very much, you wind up with a zoni. It's fun to think of animal hybrids as the Reese's peanut butter cups of nature.

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Encyclopaedia entry

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Liger, offspring of a lion and a tigress. The liger and the tigon (the result of mating a tiger with a lioness) possess features of both parents, in variable proportions, but are generally larger and darker than either. It is thought that most, if not all, male ligers and tigons are sterile.

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Big Cat Rescue is dedicated to the ethical treatment and conservation of big cats. Join our mission to end abuse in captivity and protect wild cats in their natural habitats.

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Photos and videos of wildlife, places, and nature from WWF.

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By Michael Evans - 06 Dec 2010 10:11:0 GMT

The bleak future for polar bears as global warming encourages brown bears to range further north. Something that is not widely realised is that polar bears only evolved as a distinctive species as recently as 200,000 years ago during the Pleistocene.

It is believed that today's polar bears are descended from a group of brown bears that became isolated by glaciers in an area near Siberia and underwent a rapid series of evolutionary changes in order to survive and adapt to Arctic life. These involved a change in the colour of their fur, the shape of their body, sharper teeth and large feet with thick, curved, non-retractable claws that are used for grasping prey as well as providing vital traction when running or climbing on ice.

Polar Bears are the world's largest land carnivore and the only member of the bear family that is entirely carnivorous. They live on a diet entirely composed of seal flesh and blubber. As a result of this relatively rapid evolution into a semi-aquatic Arctic life with a very specialised diet, the polar bear has developed a cranial morphology that is weaker than that of brown bears and less suited to processing tough omnivorous or herbivorous diets.

Polar bears live almost exclusively on the flesh of young ringed or bearded seals. They have 42 teeth and have developed blade-like incisors to shear off pieces of flesh, with strong canine teeth to grasp prey and tear tough hides. Since they swallow most of their food in large chunks rather than chewing it first, strong molars are not necessary and these are much smaller than those of their brown cousins. While their teeth are super-efficient for processing seal flesh and blubber, polar bears' teeth are less suited for processing bones and hard-to-chew diets with lots of vegetation.

The polar bear's low, flat skull with its high-sitting eyes is ideal for a semi-aquatic life and it gives them the advantage of being able to thrust their heads into breathing holes or puppy dens.

A recent study by the on-line research journal PLoS One (Public Library of Science) says that although the heads and muscle power of polar bears and brown bears are similar, tests reveal that the polar bear's skull is a 'weaker, less work-efficient structure' and does not appear to be well-suited to large amounts of chewing.

Although brown bears will eat animals when they are available, they will also eat a large amount of plant material in the summer, which all requires a considerable amount of chewing before it can be swallowed.

It is estimated that the world population of polar bears is between 20,000 and 25,000, of which about 60 per cent live in Canada, but the study concludes that as the earth warms and the brown bears continue to range northwards, this is likely to present polar bears with a significant challenge. Where Arctic foxes overlap with red foxes, it is always the red foxes that end up controlling the prime feeding and breeding areas and the fear is that polar bears will share a similar fate.

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Topics: Bears

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The bleak future for polar bears as global warming encourages brown bears to range further north. Something that is not widely realised is that polar bears only evolved as a distinctive species as recently as 200,000 years ago during the Pleistocene.

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Despite apparent differences in size and colour, grizzly vs black bear are often difficult to tell apart. Why is this important? Every year, black bear hunters kill several grizzly bears by mistake, which can have dire consequences for local grizzly bear populations.

It is also extremely important to know which species is which when you encounter a bear in your community or in the backcountry.

Black bears can be black, blue-black, dark brown, brown, cinnamon and even white. Grizzlies, likewise, may range in colour, from black to blond. Although grizzly bears are, on average, significantly larger than black bears, size is not a good indicator of which species is which. Male black bears in Manitoba's Riding Mountain National Park, for instance, can weigh up to 800 pounds in the fall, and female grizzly bears on Alberta's Eastern Slopes can weigh as little as 250 pounds in the spring.

The best indicators are the size of the shoulders, the profile of the face and the length of the claws. The grizzly bear has a pronounced shoulder hump, which the black bear lacks. Grizzlies have a concave or "dished" facial profile, smaller ears and much larger claws than the black bear. Black bears have a flatter, "Roman-nose" profile, larger ears, no visible shoulder hump and smaller claws.

Not all black bears are black and not all grizzlies are "grizzled"

Despite the names grizzly and black, coat color is the least reliable characteristic for identifying bears. For instance, grizzlies may be pale-almost luminous blond, or reddish blond, light brown, darker brown, or almost black. To add to the confusion, the common name grizzly is derived from the term "grizzled," which refers to white-tipped hair. Grizzled hair occurs mainly on the back and shoulders; thus, from a distance, a grizzly bear appears to have darker legs and lighter upper parts. And to complicate matters just a bit more, black bears, despite their name, are not always black. They can also be brown, cinnamon, blond, or a combination of light and dark hair. Kermode/Spirit/Ghost bears, found in Northwestern BC, Canada, can be white.

Just like hair color, body size is unreliable for identification

Just like color, body size is also not a reliable indicator for identifying bears. Most people tend to overestimate the weight and size of bears. A typical adult female grizzly weighs 200-350 pounds and adult males weigh 300-650 pounds. An adult black bear, which can easily weigh 200-300 pounds, may not only weigh the same as a female grizzly but also be about the same height (3-3½ feet at the shoulder). Then too, an adult male black bear will be much heavier and taller than a young grizzly. And just in case it isn't difficult enough yet, try to imagine yourself distinguishing a juvenile dark-haired grizzly from an adult cinnamon-colored black bear in the dim light of an early morning or the long dusky shadows of an early fall evening. Even under the best of conditions you'll find it's nearly impossible to judge the size and weight of a bear in the wild. Other characteristics such as diet, behavior, and habitat use are even less reliable because black bears and grizzly eat similar food, display similar behaviors, and occupy much of the same areas in some provinces and states.

Shoulder hump

Grizzly bears have well-developed shoulder muscles for digging and turning over rocks. These muscles appear as a prominent shoulder hump between the front shoulders, which is visible in profile. Black bears have no shoulder hump. A black bear's highest point, when it's on all fours, is the middle of the back or the rear, depending on how the bear is standing.

Facial profile

A grizzly typically has a concave or dishshaped profile that extends from between its eyes to the end of its nose. A black bear normally has a fairly straight profile from forehead to nose tip. A grizzly's muzzle is broader and more prominent; their eyes appear closer together and deeper set. Black bears look more dog-like and have flatter, shorter fur. Grizzlies appear to have longer, fuzzier looking fur, especially on the face.

Ear shape

Grizzly bears have smaller, more rounded ears (in proportion to their head size), that are much fuzzier looking (the fur is longer). Whereas the ears of a black bear appear larger, longer, more erect, and pointed. As seen below, you will have to take into account, whether the angle at which you are looking at the bear. If the grizzly bear has been swimming, his/her ears will appear bigger relative to the wet head.

Front claws

Long claws on the front paws are also a good way to differentiate a grizzly from a black bear. For obvious reasons, this method has its limitations! Grizzly bears have gently curved, often light-colored, two- to four inch long claws adapted for digging roots and excavating a winter den or small prey. The claws of an adult grizzly can be longer than a person's finger. Black bears have shorter, more sharply curved, dark claws that are often much less than two inches long. These claws are well adapted for climbing trees and tearing into rotten logs in search of insects.

Tracks

Compared to a black bear's tracks, grizzly tracks of the front feet are more square. If you take a straight edge and hold it across the track of a grizzly front foot, just in front of the pad and behind the toe on either side, it will not cross the toe on the other side of the foot. A black bear front track is more rounded and a straight edge will cross the toe on the other side of the foot.

Take a test to see if you can tell the difference.

For more information about the world's eight bear species, including black bears and grizzly bears, visit the website of the International Association for Bear Research & Management.

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Grizzly vs Black Bear | Know the Difference - BearSmart.com

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Despite apparent differences in size and colour, grizzly vs black bear are often difficult to tell apart. Why is this important? Every year, black bear hunters kill several grizzly bears by mistake, which can have dire consequences for local grizzly bear populations.

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Bear With Us | Black Bear Rehabilitation, Education, Research, Bear Facts

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To view photographs in a larger format, click on photo. When finished click on back arrow.
1-North American Black Bear - Ursus Americanus - colour - black, bluish-black, brown, white (Kermode or Spirit bear). The North American Black Bear is the most common bear in North America ranging from the State of Florida north, into Canada and north to Alaska. The black and brown colour phase of the black bear is common. The white colour phase is more rare occuring in north western British Columbia, Canada. The black bear is omnivorous. Their diet is mostly vegetable matter. Males reach full size at about 8 years of age. Females mate and produce cubs at 5 to 7 years of age, 8 years and older in the boreal forest regions(Ontario). Males weigh up to 280kg(600 pounds), occasionally much more. Black bears live up to 25 years in the wild. Older bears have been documented, however the majority of bears never reach old age due to human activity (hunting). Credits-two white(Kermode)black bear photos-Charlie Russell, text, photos-Mike McIntosh

- Ursus Arctos - Several subspecies. The Brown Bear can be found in Alaska, western Canada,and parts of Washington, Montana and Wyoming. Small individual populations are scattered throughout parts of Europe and Asia. Russia has a healthy population of brown bears currently. Brown bears range in colour from almost black, brown to very light brown or blonde. Size varies greatly depending on geographic location and general food availability. The largest bears, the "Big Browns" exist along the coast of Alaska and Russia growing to very large sizes rivaling that of the Polar Bear. The interior bears of the North American Rocky Mountains (Grizzly Bear) and the mountains of Europe tend to be much smaller. The really big bears (1500pounds/700kg and bigger) are now very rare. Credit -text- Mike McIntosh, photographs of brown bears - Charlie Russell-www.cloudline.ca .

3-Polar Bear - Ursus Maritimus Polar bears are among the largest bears in the world. Adult males may reach 800 kilograms (kg) or 1760 pounds (lbs). In Ontario, the largest male bear recorded from "live capture" research studies weighed 654 kg (1439 lbs). The average weight of male polar bears in Ontario is about 500 kg (1100 lbs). Adult female bears are smaller and average around 300 kg (660 lbs); their peak weights do not usually exceed 400 kg (880 lbs). Credit -text- Ontario Ministry of Natural Resources. polar bear photographs - Roy de Haas/Agami.nl

4-Asiatic black bear, Himalayan black bear, moon bear - Ursus thibetanus Asiatic black bears have long black fur with a distinct white patch on the chest that is often crescent-shaped. The fur around the shoulders and throat is particularly long, and their ears are relatively large. Asiatic black bears live in eastern Asia, including Afghanistan, Bangladesh, Bhutan, Cambodia, China, India, Islamic Republic of Iran, Japan, Democratic People's Republic of Korea, Lao People's Democratic Republic, Malaysia, Mongolia, Myanmar, Nepal, Pakistan, Russian Federation, Taiwan and Vietnam. Asiatic black bears are more carnivorous than their American counterparts, although only a small part of their diet is made up of meat. This includes small mammals, birds, fish, molluscs and carcasses. They also feed on grasses, fruits, berries, seeds, insects and honey. In autumn they fatten up for the winter by feeding on nuts. In northern climates they hibernate. In southern climates they do not hibernate. Credit -text- BBC Science and Nature. Photos courtesy of Wildlife S.O.S.

5-Andean Bear or Spectacled Bear - Tremarctos ornatus Most scientists refer to spectacled bears as Andean bears (they are found only in the Andes mountains in South America). The bears are an endangered species, listed as Vulnerable, and it is illegal to kill them. The Andean bear is the last remaining short-faced bear (subfamily Tremarctinae) and the closest living relative to the Florida spectacled bear and short-faced bears of the Middle Pleistocene to Late Pleistocene age. Spectacled bears are the only surviving species of bear native to South America, and the only surviving member of the subfamily Tremarctinae. The Spectacled Bear is technically the largest land carnivore on that continent, although as little as 5% of its diet is composed of meat. South America's largest obligate carnivore is the jaguar. Among South America's extant, native land animals, only the Baird's and South American Tapirs are heavier than this species. The Spectacled bear is a mid-sized species of bear. Overall its fur is blackish in color, though bears may vary from jet black to dark brown and to even a reddish hue. The species typically has distinctive beige-coloured marking across its face and upper chest, though not all Spectacled bears have "spectacle" markings. The pattern and extent of pale markings are slightly different on each individual bear and bears can be readily distinguished by this. Males are a third larger than females in dimensions and sometimes twice their weight. Males can weigh 100 - 200 kilograms (220 - 440 lb), and females 35 -82 kilograms (77 - 181 lb). Length can range from 120 to 200 cm (47-79 in), with a tail length of a mere 7 cm (2.8 in), and shoulder height from 60 to 90 cm (24-30 in). Compared to other living bears, this species has a more rounded face with a relatively short and broad snout. In some extinct species of the Tremarctinae subfamily, this facial structure has been thought to be an adaptation to a largely carnivorous diet, despite the modern Spectacled bears' herbivorous dietary preferences. Credit -text- Wikipedia. Photo credits-files from the Wikimedia Commons.

6-Panda Bear - Ailuropoda melanoleuca Length: 5 ft (1.5m) (with a 6 inch(.2m)tail). Weight: Around 250 lbs (113 kg) (males); around 220 lbs (100 kg) (females). The giant panda is a rare, endangered and elusive bear. Science used to believe that the giant panda was a member of the raccoon family. With DNA analyses science proved itself wrong. The giant panda and the red panda are not related. Giant pandas are famous for their love of bamboo, a diet so nutritionally poor that the pandas have to consume up to 20kg each day. The extra digit on the panda's hand helps them to tear the bamboo and their gut is covered with a thick layer of mucus to protect against splinters. Habitat loss is the greatest cause of the giant panda's decline, and today their range is restricted to six separate mountain ranges in western China. A giant panda is born pink, hairless, blind and 1/900th the size of its mother. Unlike other bears, giant pandas do not hibernate. In the winter, they move to lower elevations to keep warm, while traveling to higher elevations in the summer to stay cool. They can be active at any time of the day or night. Credits- text- various sources. Photo credits-www.amazing-world-in-free-stock-pictures-and-photos.com.

7-Sloth bear-Melursus (Ursus) ursinus -Two subspecies: Sri Lankan Sloth Bear and Indian Sloth Bear. Body length: 140-190cm, Weight: male: 80-140kg, female: 55-95kg. These shaggy-haired bears can be heard sucking up termites a long distance away. Sloth bears are stocky with long, shaggy, black hair and a white U- or Y-shaped marking on the chest. They have large lips, a long tongue, a pale muzzle and well-developed hook-like claws that enable them to climb trees and dig for termites. Sloth bears live in Sri Lanka, India, Bhutan, Nepal and Bangladesh. Sloth bears are nocturnal and occupy home ranges that they seem happy to share with other sloth bears. Male sloth bears have an average range of 13 square km. This is much smaller than most other bears, probably due to the fact that they do not suffer from seasonal fluctuations of food supply (ants and termites are available all year round). The constant availability of ants and termites also mean that they do not need to undergo a winter sleep. Credit -text- BBC Science and Nature. Photo credits - Photos on left(2) of Sri Lankan Sloth Bears by photographer Cai Priestley - www.toothandclawphotography.com. Photos on right(2) - Indian Sloth Bear - courtesy of Wildlife S.O.S.

8-Sun Bear - Ursus malayanus - Body length: 120-150cm, Weight: female 27-50kg, male 27-65kg. They are the smallest species of bear. Sun bears have short black/dark brown water-repellent fur, with a yellow crescent on their chest. They have strong paws with naked soles and long sickle-shaped claws. They have flexible snouts and very long tongues, which are an adaptation for extracting termites from nests. Relatively(to their size), they have the largest canines of all the bear species. Canine teeth are specialised for tearing meat, but sun bears are not particularly carnivorous. They may use their sharp canines as weapons or as tools for tearing at trees to get at insects. Sun bears live in south east Asia: Brunei Darussalam, Cambodia, China, India, Indonesia, Lao Peoples Democratic Republic, Malaysia, Myanmar, Thailand and Vietnam. Credit -text- BBC Science and Nature. Photographic credit - Bornean Sun Bear Conservation Centre (BSBCC).

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The Eight (8) Bear Species of the World | Bear With Us

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To view photographs in a larger format, click on photo. When finished click on back arrow. 1-North American Black Bear - Ursus Americanus - colour - black, bluish-black, brown, white (Kermode or Spirit bear). The North American Black Bear is the most common bear in North America ranging from the State of Florida north, into Canada and north to Alaska.

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Ladybird facts for kids | National Geographic Kids

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Calling all budding young naturalists! It's time for the lowdown on one of our planet's most beautiful bugs ...check out our cool ladybird facts ... Scientific name: Coccinellidae septempunctata (seven-pot ladybird) Family name: Coccinellidae Classification: Insect IUCN status: Not Evaluated Lifespan (in wild): Around one year (two years maximum) Body length: Up to 1cm Top speed: 24km/h Diet: Mostly carnivores Habitat: Grasslands, forests, cities, suburbs and along rivers.

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If you've ever watched a nature program, or gone on a perilous trek of your own somewhere in the wilds of the world, then you're probably familiar with (and a bit wary of!) snakes. There are nearly 3,000 different species of snakes in the world, and more than 10% of these are venomous. Of that 10-15%, a very small portion are actually dangerous to humans.

Even so, the fear of being bitten by a poisonous snake still runs rampant through global cultures, because we have heard about or seen the terrible and fast-moving effects that snake venom can have on a body (Hollywood has made sure we're aware of the power of snake venom!)

That being said, if snake venom is so powerful and deadly, why doesn't it poison the snake? After all, the snake is slithering around with a bunch of venom inside, right?

The Science of Snake Venom

What is snake venom?

Snake venom is a special form of saliva that contains a range of zootoxins and is stored in something akin to our salivary gland. Once the venom is created and stored in these glands, it does not move back through the body, where it could infect other tissues, just as it does in their prey. The toxic venom is stored in these specially protected glands until it is moved down through narrow tubules in the fangs and delivered into the snake's prey.

How does snake venom work?

This is a common question for those fascinated by the mysteries of Nature, as well as those who are deathly afraid of snakes. To understand this fully, we should first understand a bit about snake venom, as well as the mechanisms snakes have developed over millions of years.

Snake venom is primarily made up of proteins, the vast majority of which are broken down in the stomach, just like the proteins found in meat and beans. In other words, eating a protein-based poison wouldn't be very harmful, as they would be neutralized in the stomach. However, if that venom somehow bypassed your stomach or entered your bloodstream in another way (such as through a bite), then the toxins wouldn't break down and would begin to do real damage to your organ systems, typically in the form of necrosis and hemorrhage. When these toxic proteins are broken down in the stomach, they are separated into their simple, harmless amino acids.

The same thing is therefore true for snakes, in terms of eating their food. Those protein poisons function to debilitate and digest prey, in addition to natural defense, so snakes are exposing themselves to their own poison when they eat their food. However, when they devour that small animal (or even another snake), they are able to neutralize their own venom through this protein breakdown process while they digest their food.

Why doesn't the venom affect the snake?

Other than breaking it down in their digestion tract, snakes have adapted these glands to prevent any undue exposure to their own venom, there is a low level of exposure (Nature isn't perfect, after all). This has led most researchers to believe that as snakes evolved, they developed antibodies to protect themselves from their own particular blend of venom. Research has shown that snakes of the same species often do not use their venomous attacks when fighting for territory or mates. This may be explained because the snakes know that their venom won't necessarily provide an advantage in the fight, so they conserve it and use their brute strength to win.

However, snakes do not have antibodies for ALL types of venom, and there are hundreds of different venomous snake species in the world. Also, some venomous snakes eat non-venomous snakes, who are definitely affected by their toxic bite.

Furthermore, some snakes are susceptible to large concentrations of their own venom, as they've only developed tolerance to handle a low level of exposure. Therefore, if certain snakes bite their own tail, mistaking it for prey, and injecting a full dose of venom, the quick-acting venom could damage the musculature or cause low levels of necrosis. There is a relatively low chance of the snake dying, but definitive research is lacking in this field, given the ethical and logistical complications of researching snake fights to the death.

Snakes appear to be expert managers of their internal toxin levels, crafty about who they pick fights with, and reliant on the protein breakdown powers of their stomach, all of which keep them protected from their own venom and the venom of most other snakes.

They're formidable and fascinating creatures, to say the least. It takes a pretty confident creature to spend its life with deadly sacs of poison stored right behind its eyes!

References

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How Does Snake Venom Kill Humans? Why Doesn't It Kill The Snake Itself

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Snake venom is a special form of saliva that contains a range of zootoxins and is stored in something akin to our salivary gland. Once the venom is created and stored in these glands, it does not move back through the body

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australia’s animals; mammals; marsupials; monotremes; birds; reptiles; marine animals

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Australia teems with native animals, many which are found only here.

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Native Australian Wildlife Which Animal is Native to Australia?

Ever wondered what animals are really native to Australia? Generally speaking, it is any animal that has been in Australia before the arrival of humans. The reason this definition is the best is because animals such as the koala and emu have been in Australia for millions of years and are unquestionably native. The dingo, on the other hand, which considered native by some, was only brought to Australia by humans about 5,000 years ago. Many other animals such as camels and rabbits were introduced by European settlers less than 200 years ago. These animals are definitely not native to Australia.
*Related Article: Why Australian Animals are Different
There Were No
Mice, Apes & Monkeys
in Australia

Until Europeans came to Australia in 1788, there were no hoofed animals (like horses, cattle, goats, deer, etc.) in Australia. There were no apes or monkeys in Australia either.

Rats and mice were the only animals that the Europeans didn't bring intentionally. They arrived as stowaways on ships.

Australian Mammals Types of Native and Introduced Mammals in Australia

There are three types of mammals in Australia. These are monotremes, marsupials, and placentals.

Monotremes first appeared between 145-99 million years ago and are the oldest type of Australian mammals. Two out of the five known species of monotremes in the world live in Australia. The echidna and platypus are two such animals found in Australia.

Marsupials appeared about 64-65 million years ago and are the second oldest type of mammal found in Australia. They occupy every niche of the Australian habitat and range from the large red kangaroo to marsupials smaller than a mouse.

Placental mammals are relatively recent arrivals to Australia. Bats were the first to arrive, getting here about 23 million years ago. Rodents arrived about 5-10 million years ago. These animals reached Australia by flying or hitching a ride on floating debris and crossing the oceans that separated Australian from Asia as Australia as it stated drifting slowly closer to Asia. These placental mammals make up a very small percentage of the total mammalian population. Humans introduced several animals. The dingo was the first of these, coming here about 5,000 years ago. Beginning in 1788 many types of placental mammals such as cattle, the fox and rabbit were brought to Australia.
*Related Article: Difference Between Marsupials, Placental & Monotreme Mammals
Australian Amphibians and Reptiles Some are the Most Poisonous Snakes

Australia has many amphibians, and reptiles found nowhere else in the world.

Lizards - There are over 700 species unique to Australia alone.

Snakes - Australia has 140 species of land snakes and 32 species of sea snakes. Of these about a 100 are poisonous snakes. The bite from about 12 of these can be fatal to humans. The taipan and red-bellied black snake are some such poisonous snake.

Frogs - Four families of native frogs numbering 230 species inhabit the continent. 135 of these are unique to Australia.

Crocodiles - Australia has two species of crocodiles. The Saltwater crocodile is the world's largest and can weigh as much as 1,000 kilos and is known to attack humans. Freshwater crocodiles are much smaller and do not attack humans.

Turtles - There are 35 species of freshwater turtles. Six species of sea turtle also visit the coastlines.

Australian Birds Desert, Outback and Rainforest Birds of Australia

Australia has 800 species of birds of these 350 are only found in Australasia.

Ratites such as the emu and cassowary are large flightless birds similar to the ostrich. The Emu lives in the Australian Outback. And the critically endangered cassowary lives in the tropical rainforests of Australia.

Megapods such as the Mallee fowl, trace their ancestry as far back as Gondwanan time. These stocky birds look somewhat like chickens, but they have small heads and large feet (that's why the name "megapod" meaning big-feet). These birds are usually found in forested areas.

Parrots unique to Australia comprise nearly 20% of the world's know species. These include the cockatoo and the almost extinct night parrot, which lives in the Australian desert.

Other birds such as Kookaburras are the world's largest kingfishers.

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Australian Native Animals - 100 Australian Animals A-Z List

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Ever wondered what animals are really native to Australia? Generally speaking, it is any animal that has been in Australia before the arrival of humans. The reason this definition is the best is because animals such as the koala and emu have been in Australia for millions of years and are unquestionably native.

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Enyclopaedia entry

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Bilby: Bilby, (Macrotis lagotis), small, burrowing, nocturnal, long-eared marsupial belonging to the family Thylacomyidae (order Peramelemorphia) and native to Australia. Prior to the arrival of Europeans, bilbies occupied habitats across more than 70 percent of Australia. At present, however, they are

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Why do things have to ? What a great question that has been asked by many of our Wonder Friends. In fact, it's a question that every human being has surely thought about at one time or another.

At some point in time, every single person comes face-to-face with the reality of his or her . All things that live will eventually . It's a fact of , but it can be hard to face at times. When we lose a beloved pet or a special loved one, the loss can be devastating and difficult to cope with.

So why can't we live forever? There are philosophical and religious aspects to that question that are way beyond the scope of this Wonder of the Day. We can, however, look at some of the , scientific aspects that will shed light on that question. We'll also look at how we might live longer in the future, even if we can't live forever.

Death is an essential part of the of . Whether you're talking about a human being, an animal, or a plant, every living thing comes alive at some point. For humans and animals, the first step in the of is birth.

From birth onward, the cycle is focused on survival. If we survive, we grow and mature. At some point, our bodies begin to age more rapidly until our eventual death ends the cycle.

To survive, most living things need food, water, sunlight, and oxygen. For human beings and animals, these things are usually supplied by our parents until we're able to provide them for ourselves. For human beings, survival is usually fairly easy, and we're able to concentrate on many other enjoyable aspects of .

For some humans, most animals, and nearly every other form of , survival is a day-to-day task that requires effort and energy. Because survival can be such a struggle, the cycle of some organisms is very short. For example, the cycle of a typical can be as short as a week. On the other hand, bristlecone pine trees can live for thousands of years.

Today, adult human beings have a expectancy of 75-80 years. About 200 years ago, that expectancy was only about 35 years. So you can see that we've more than doubled our average expectancy over the past couple hundred years. Advances in medicine and technology have had a lot to do with that. Do you think the next hundred or so years could see another doubling of expectancy ?

Some scientists think so. There are many scientists today who continue to work on solving the problems that cause human beings to age and . As we get older, our bodies eventually wear out. Many times they to various diseases that cause death. Some scientists identify these natural events as problems to attempt to solve scientifically.

For example, can scientists identify the reasons why we age? If so, can they invent ways to stop the aging process? Likewise, can scientists figure out how to eliminate all diseases and health problems that might lead to death?

If you look around at the products available in stores today, not to mention the advances in modern medicine you can see at most hospitals, it's clear that scientists are working hard on these issues. They're also experiencing many successes along the way. Even though true immortality may be a long ways off - and ultimately maybe only the stuff of fairy tales - scientific progress is definitely helping us to live longer lives.

As you ponder these and death issues, it may help also to consider whether you would want to live forever if you could. What would the benefits be? What negative consequences could you imagine? What might Earth look like if no one ever died?

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Why do things have to ? What a great question that has been asked by many of our Wonder Friends. In fact, it's a question that every human being has surely thought about at one time or another. At some point in time, every single person comes face-to-face with the reality of his or her .

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As Sumatran rain forests fall to palm oil plantations, their critically endangered tiger may soon vanish from the planet.

There are now only two regions on the Indonesian island with enough breeding females to sustain the species, according to a new study.

Watch Big Cat Week on NatGeo WILD all week, starting Sunday, December 10 at 9/8c.

"The erosion of large wilderness areas pushes Sumatran tigers one step closer to extinction," says study leader Matthew Luskin, research fellow with the Smithsonian Institution who's based at Nanyang Technological University in Singapore.

The Sumatran is the smallest of the nine original subspecies-males rarely grow to eight feet long.

Despite successful anti-poaching efforts, the Sumatran tiger population has declined about 17 percent since 2000, to just 600 animals left in the wild. Tigers on the neighboring islands of Java, Bali, and Singapore went extinct in the 20th century. ( Read how some tiger populations are rising.)

That's largely because, between 2000 and 2012, some 17 percent of prime tiger habitat was torn down, mainly for oil palm plantations, which covers nearly 30 million acres of the country.

"Sumatra has one of the highest rates of deforestation in the world," adds Luskin, who received funding for his research from the National Geographic Society.

Using images and videos from hundreds of infrared camera traps set up in two national parks, Luskin and his team identified individual tigers by their unique stripe patterns. This provided an estimate of how many tigers live in a given area. (Read: " How Many Tigers Are There Really? A Conservation Mystery.")

This new information was combined with data from 17 previous estimates of tiger population density.

The results revealed that tiger numbers are twice as high in primary versus degraded, or logged, forests-highlighting the extreme importance of primary forest to the survival of the species.

Luskin and colleagues' global conservation strategyfor tigers depends on maintaining a network of "secure source populations" with at least 25 breeding females in suitable habitat large enough to have more than 50 breeding females.

Sixty years ago Sumatra likely had a dozen of these secure source populations across the island. Today there are just two: Sumatra's Kerinci Seblat National Park and Gunung Leuser National Park, in the northern part of the island.

"We set up a bunch of cameras inside Kerinci Seblat National Park, but when we returned to retrieve them 10 weeks later, I was shocked to see about 50 hectares of the forest had been clearcut," says Luskin, whose study was published December 5 in the journal Nature Communications.

Illegal logging in Kerinci Seblat is a major threat to other species, as well. "It's an incredibly beautiful jungle with endangered Sumatran elephants, clouded leopards, and many others species. It should be a conservation priority." ( Learn about the National Geographic Society's Big Cats Initiative.)

Many local and international groups are working to preserve the forests; the Indonesian government is also on board, but needs do a lot more, he adds. In 2014, under pressure from conservation groups, the big oil palm companies adopted a no-deforestation policy.

Found in a huge array of products, from shampoo to cosmetics to chocolate bars, palm oil is one of the world's most commonly used vegetable oils. ( Read about the human cost of Indonesia's palm oil plantations.)

"Flying over Sumatra is like flying over an ocean of oil palm plantations," adds co-author Mathias Tobler, a scientist with San Diego Zoo Global. "There's no question that it's the main driver of deforestation."

"Safeguarding the remaining expanses of primary forests is now absolutely critical to ensuring tigers can persist indefinitely on Sumatra," Tobler says.

At the end of the day, Luskin says he's optimistic about the future of the Sumatran tiger.

"People love tigers. They really want to protect them and it's easier to do now that there's less forest to protect."

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Extremely Endangered Tiger Losing Habitat-and Fast

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As Sumatran rain forests fall to palm oil plantations, their critically endangered tiger may soon vanish from the planet. There are now only two regions on the Indonesian island with enough breeding females to sustain the species, according to a new study. Watch Big Cat Week on NatGeo WILD all week, starting Sunday, December 10 at 9/8c.

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TIGERS IN CRISIS: THE PROBLEMS

In order to live in the wild, tigers need water to drink, animals to hunt, and vegetation in which to hide. As the mountains, jungles, forests, and long grasses that have long been home to tigers disappear, so, too, do tigers.

Agricultural expansion, timber cutting, new roads, human settlement, industrial expansion and hydroelectric dams push tigers into smaller and smaller areas of land.

These forest fragments are surrounded by rapidly growing and relatively poor human populations, including increasing numbers of illegal hunters.

Without wilderness, the wild tiger will not survive.
CONTINUE TO HABITAT LOSS

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TIGERS IN CRISIS: THE PROBLEMS In order to live in the wild, tigers need water to drink, animals to hunt, and vegetation in which to hide. As the mountains, jungles, forests, and long grasses that have long been home to tigers disappear, so, too, do tigers.

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The Status of Tigers in the Wild

Of the original nine subspecies of tigers, three have become extinct in the last 80 years; an average of one every 20 years. It has been predicted all tigers may become extinct in the wild within the next decade. Poaching, habitat loss and fragmentation have reduced the global population of tigers from over 100,000 in the 1900′s, to less than 4,000 in the 1970′s.

Today, four of the remaining subspecies of tigers are considered endangered by the IUCN, while two of the subspecies are considered "critically" endangered. The total number of all the wild populations of the six remaining subspecies of tigers (Bengal, Indochinese, Malayan, Siberian, South China, and Sumatran) is estimated to be between 3,000 - 3,600 tigers.

Remaining Tiger Subspecies:

Bengal tigers (Panthera tigris tigris): are the most numerous tiger subspecies with its remaining wild populations estimated at around 2,500. The Bengal tiger roams a wide range of habitats including high altitudes, tropical and subtropical rainforests, mangroves, and grasslands. They are primarily found in parts of India, Nepal, Bhutan and Bangladesh. Bengal tigers are sometimes called Indian tigers and account for over half of all tigers remaining in the wild. Poaching for tiger parts is their major threat. The Bengal tiger is classified as endangered by the IUCN.

Indochinese tigers (Panthera tigris corbetti): are located in Thailand, Cambodia, China, Lao PDR, Myanmar and Vietnam. The population of this subspecies had fallen by more than 70 percent in slightly more than a decade, and the total population of Indochinese tigers is estimated at fewer than 300 individuals. However, due to restricted access to areas where the Indochinese tiger lives, little is known about their population status. Human development, such as road construction is fragmenting habitats. And decades of poaching has also contributed to their rapid decline. The Indochinese tiger is classified as endangered by the IUCN.

Malayan tigers (Panthera tigris jacksoni): are found only on the Malay Peninsula and in the southern tip of Thailand. They were recently recognized as a new subspecies closely related to -but being genetically distinct- from the Indochinese tiger. Habitat fragmentation due to development projects and agriculture, along with commercial poaching are serious threats to the remaining 500 Malayan tigers. In Malaysia there is a very active market for tiger meat and manufactured tiger bone medicines. The Malayan tiger is classified as endangered by the IUCN.

Siberian tigers or Amur tigers (Panthera tigris altaica): are found mainly in the Sikhote Alin mountain region and the southwest Primorye province in the Russian Far East. It is estimated there are around 300 Siberian tigers in this region with small pockets of Siberian tigers in China and North Korea. The primary threats to the survival of Siberian tigers are poaching and habitat loss from intensive logging and development. The Siberian Tiger is classified as endangered by the IUCN.

South China tigers (Panthera tigris amoyensis): are the smallest of all the tiger subspecies; it is also the most critically endangered. Little is known about their exact numbers in the wild, but some estimates would put the number at under 20 tigers. Others would say that estimate is high and that the South China tiger is extinct in the wild. The reality is that no South China tiger has been seen in the wild for the last 20 years. The South China tiger was native to the provinces of Fujian, Guangdong, Hunan, Jiangxi in southern China. However now, the less than 100 South China tigers that remain on the face of the earth, are found only in Chinese zoos. The South China tiger is classified as critically endangered by the IUCN.

Sumatran tigers (Panthera tigris sumatrae): are found only on the Indonesian island of Sumatra off the Malaysian Peninsula. Their habitat ranges from lowland forest to mountain forest and includes evergreen, swamp and tropical rain forests. It is estimated that only between 500-600 Sumatran tigers remain in the wild, and the actual number may be as low as 400. The major threats to Sumatran tigers are habitat loss due to expansion of palm oil plantations, the planting of acacia plantations and illegal trade for tiger parts and products. The Sumatran tiger is classified as critically endangered by the IUCN.

Extinct Tiger Subspecies:

The Bali tiger (Panthera tigris balica): is an extinct subspecies of tiger which was found solely on the Indonesian island of Bali. It was one of three subspecies of tigers found in Indonesia, together with the Javan tiger, which is also extinct, and the critically endangered Sumatran tiger. It was the smallest of the tiger subspecies. Bali tigers were last positively recorded from western Bali in the late 1930s. The Bali Barat National Park was established in 1941 in tiger habitat, but it is likely that Bali tiger became extinct by the end of World War II or possibly as late as the early 1950s. The causes of extinction include hunting and loss of forest habitat and prey base. There are no Bali tigers in captivity.

The Caspian tiger (Panthera tigris virgata): is an extinct tiger subspecies with the last records in the wild dating to the early 1970s. The Caspian tiger is also known as the Hyrcanian tiger, the Mazandaran tiger, the Persian tiger and the Turanian tiger. Caspian Tigers were found in the sparse forest habitats and riverine corridors west (Turkey) and south (Iran) of the Caspian Sea and west through Central Asia into the Takla Makan desert of Xinjiang, China. Its extinction can be attributed to hunting of tigers and their prey, habitat loss and conversion, and increased vulnerability of small populations. The last Caspian tiger was seen in the early 1970s, and there are none in captivity.

The Javan tiger (Panthera tigris sondaica): is an extinct tiger subspecies that inhabited the Indonesian island of Java until the mid-1970s. Javan tigers were last positively recorded from Java's Meru Betiri National Park in 1976. They likely disappeared from much of the rest of the island -outside the park boundries- by the 1940s. It is estimated that only 20-25 Javan tigers remained on Java by the mid-1950s. The causes of the Bali tiger's extinction include hunting of the tiger, along with loss of forest habitat (destroyed for agriculture uses) and the demise of the tigers prey base. There are no Javan tigers in captivity.

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Of the original nine subspecies of tigers, three have become extinct in the last 80 years; an average of one every 20 years. It has been predicted all tigers may become extinct in the wild within the next decade.

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Here, the carnivorous sundew plant growing on the foothills of Mt. Cameron, in northeastern Tasmania. Researchers have found the plant's snappy tentacles can capture an insect in just 75 milliseconds.

Credit: MFdeS, Wikimedia Commons

The twitchy tentacles of a sundew can catapult prey into the carnivorous plant's sticky traps in a fraction of a second, researchers say.

These fast-moving snares are among the quickest seen yet in the plant kingdom, the scientists added.

Researchers investigated a sundew plant from southern Australia, Drosera glanduligera, whose "flower" trap grows up to 1.5 inches (4 centimeters) wide. Sundews get their name from the sticky drops resembling the morning dew at the end of each of their tentacles. Carnivorous plants such as sundews go after meat to help them survive in the nutrient-poor soils they call home.

Past research showed D. glanduligera has a way of ensnaring prey that is unique among carnivorous plants. In addition to its sticky tentacles, this sundew possesses longer, touch-sensitive tentacles that can snap forward, hurling insects at its flypaper-like glue traps. The sticky tentacles then slowly bend to move the prey to spoon-shaped leaves, from where it is slowly digested.

The snap tentacles (shown here) of the sundew plant are among the quickest seen yet in the plant kingdom.

Credit: Poppinga et al. / PLoS ONE 7(9): e45735. doi:10.1371/journal.pone.0045735

"Although the fast snap tentacles were basically known for decades, they received only very little attention from the scientific community," said researcher Thomas Speck, a biophysicist at the University of Freiburg in Germany. [ Image Gallery: Wacky Carnivorous Plants]

To show for the first time how these tentacles work, scientists collaborated with private sundew cultivators. They analyzed these plants with microscopes and high-speed video cameras in the lab, testing the sundews with fruit flies.

" D. glanduligera is not only extremely tough to cultivate by needing high-temperature fluctuations between day (above 20 degrees C) and night (close to zero degrees C) and regular feeding with flaked fish food and fruit flies, it also grows for only a few months from germination until seed production and wilting," wrote researcher Simon Poppinga, a botanist at the University of Freiburg in Germany, in an email. "We hence had a very small time slot to accomplish all experiments needed." In Fahrenheit that temperature range is 68 to 32 degrees.

The secret to the quick tentacles probably involves releasing pent-up hydraulic pressure in a sudden burst, the researchers found. And it happens fast. The sundew takes about 75 milliseconds to catapult prey with snap tentacles, "which is by far the fastest motion reported from the sundew genus," Speck told LiveScience. "It is quick enough to outsmart walking prey animals, and is a bit faster than the snap-trapping action of the famous and closely related Venus flytrap and waterwheel plant."

However, the title of fastest predator in the plant kingdom belongs to another plant, the bladderwort Utricularia, "which features traps that suck in their prey in less than a millisecond," Poppinga said.

These snap tentacles are each one-shot weapons, with their hinges essentially breaking after they catapult, the researchers found. The sundew grows fast, developing new leaves every three to four days, so losing a snap tentacle to get food is apparently worth it.

The researchers suggest the snap tentacles extend the range of each plant beyond just their glue traps and perhaps help them capture larger animals that might ordinarily be strong enough to free themselves from a sticky tentacle.

Future research will endeavor to see how these carnivorous plants behave outside the lab in the wild and what prey they catch. "Fruit flies are definitely not the main prey in the natural habitat," Speck said.

The scientists detailed their findings online Sept. 26 in the journal PLoS ONE.

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How a Sneaky Sundew Hurls Insects Into Its Trap

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The twitchy tentacles of a sundew can catapult prey into the carnivorous plant's sticky traps in a fraction of a second, researchers say. These fast-moving snares are among the quickest seen yet in the plant kingdom, the scientists added. Researchers investigated a sundew plant from southern Australia, Drosera glanduligera, whose "flower" trap grows up to 1.5 inches (4 centimeters) wide.

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Encyclopaedia entry

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Sundew: Sundew, (genus Drosera), any of the approximately 152 carnivorous plant species of the genus Drosera (family Droseraceae). Sundews are widely distributed in tropical and temperate regions, especially in Australia, and are common in bogs and fens with sandy acidic soil. Predominantly perennials, the

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Research examines the cellular process behind the plant's quick bite.

Thomas Sumner, Contributor

(ISNS) -- Plants aren't typically known for their speed, but the carnivorous Venus flytrap can close its jaw-like leaves in the blink of an eye. Charles Darwin once referred to the Venus flytrap as "one of the most wonderful plants in the world." But despite the plant's notoriety, its closing mechanism remains a mystery 250 years after its discovery.

Biophysicists at the Ecole Polytechnique Universitaire de Marseille, in France, are investigating the cellular process behind the Venus flytrap's rapid response to prey. The researchers have already thrown out one popular explanation for the Venus flytrap's quick motion, that water movement within the plant makes its jaw snap. They announced this finding in San Diego at a meeting of the American Physical Society's Division of Fluid Dynamics.

"This is the first time someone has looked at how Venus flytraps move on the cellular level," said biophysicist and lead researcher Mathieu Colombani. "We are looking for an explanation that's both biologically and physically possible."

Venus flytraps are native to the coastal bogs of North and South Carolina. The bogs' soil lacks the proper nutrients -- particularly nitrogen and phosphorus -- for plants to grow. The plant manages to survive in this tough environment by trapping and digesting insects in order to fulfill their nutritional needs.

"In these bogs you see a lot of carnivorous plants that rely on animals and insects for nutrients," said biophysicist Jacques Dumais of the Universidad Adolfo Ibanez in Chile.

When an insect is drawn into one of the plant's traps, it tickles a small, hair-like outgrowth on the inside of the leaf. When two different outgrowths are triggered in short succession, a rapid process triggers the leaves to shut, trapping the insect in as little as one-tenth of a second.

As the insect struggles to escape, it triggers even more outgrowths, causing the Venus flytrap to tighten its grip and release enzymes to digest its snack. Each "mouth" can only snap shut four or five times before it dies, whether it catches something or not.

In 2005, scientists discovered the large-scale principle behind the plant's bite. Each leaf pops from convex to concave as it closes, like a jumping popper toy or an inverted contact lens.

"A Venus flytrap is like two popper toys put together," said Colombani. "Once the process is started, the two leaves snap together very quickly."

When the plant's leaves are separated, the trap is in a stable equilibrium and remains open. Once the plant's prey springs the trap, some internal process in the plant upsets the system, causing the two leaves to quickly snap together. Identifying this internal process is the focus of Colombani's research.

"The Venus flytrap's movements are as much a biological process as a physical process," said Dumais. "Colombani's work is a really wonderful attempt to understand everything from beginning to end."

Currently there are several theories on how the Venus flytrap's leaves become unstable.

The researchers were able to rule out one popular theory, which suggests that cells on the inside of the plant's leaves transfer water to cells on the outside of the leaves. The resulting cell size change would alter the shape of the leaves, possibly causing them to quickly destabilize and pop together. Colombani's team looked at the pressure change inside a single cell as the leaves snapped shut.

"It's difficult because you need to stay focused on a single cell and the plant's leaves move very quickly," said Colombani.

To solve this problem, the researchers creatively used blue dental paste to glue one of the Venus flytrap's leaves to an anchored plastic fork. This setup kept the leaf from moving and made focusing on a single cell possible. They found that the movement of water between the inner and outer cells was far too slow to be responsible for the plant's rapid movements.

"It takes a few seconds for each cell to relax, which means that it would take about two minutes for the plant to close," said Colombani. "This doesn't seem like a good candidate for a mechanism that takes less than a second."

The researchers are currently testing another popular explanation that says the elasticity of the plant's cell walls changes, causing the leaves to destabilize and snap together. Colombani says that whatever the mechanisms behind the remarkable plant's bite are, they could have potential applications in medicine or other fields.
Thomas Sumner is a science writer based in Santa Cruz, Calif.

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Investigating the Venus Flytrap's Speedy Snap

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Research examines the cellular process behind the plant's quick bite. Thomas Sumner, Contributor (ISNS) -- Plants aren't typically known for their speed, but the carnivorous Venus flytrap can close its jaw-like leaves in the blink of an eye. Charles Darwin once referred to the Venus flytrap as "one of the most wonderful plants in the world."

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Carnivorous Plants | The Dr. Binocs Show | Educational Videos For Kids

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Encyclopaedia Entry

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The Venus flytrap ( Dionaea muscipula) is a carnivorous plant native to subtropical wetlands on the East Coast of the United States in North Carolina and South Carolina. It catches its prey-chiefly insects and arachnids -with a trapping structure formed by the terminal portion of each of the plant's leaves, which is triggered by tiny hairs (called "trigger hairs" or "sensitive hairs") on their inner surfaces.

When an insect or spider crawling along the leaves contacts a hair, the trap prepares to close, snapping shut only if another contact occurs within approximately twenty seconds of the first strike. Triggers may occur with a tenth of a second of contact. The requirement of redundant triggering in this mechanism serves as a safeguard against wasting energy by trapping objects with no nutritional value, and the plant will only begin digestion after five more stimuli to ensure it has caught a live bug worthy of consumption.

Dionaea is a monotypic genus closely related to the waterwheel plant (Aldrovanda vesiculosa) and sundews (), all of which belong to the family Droseraceae.

Although widely cultivated for sale, the population of the Venus flytrap has been rapidly declining in its native range. The species is currently under Endangered Species Act review by the U.S. Fish & Wildlife Service.

The plant's common name (originally "Venus's flytrap") refers to Venus, the Roman goddess of love. The genus name, Dionaea ("daughter of Dione"), refers to the Greek goddess Aphrodite, while the species name, muscipula, is Latin for both "mousetrap" and "flytrap". The Latin word muscipula ("mousetrap") is derived from mus ("mouse") and decipula ("trap"), while the homonym word muscipula ("flytrap") is derived from ("fly") and decipula.

On 2 April 1759, the North Carolina colonial governor, Arthur Dobbs, penned the first written description of the plant in a letter to English botanist Peter Collinson. In the letter he wrote: "We have a kind of Catch Fly Sensitive which closes upon anything that touches it. It grows in Latitude 34 but not in 35. I will try to save the seed here." A year later, Dobbs went into greater detail about the plant in a letter to Collinson dated Brunswick, 24 January 1760.

The great wonder of the vegetable kingdom is a very curious unknown species of Sensitive. It is a dwarf plant. The leaves are like a narrow segment of a sphere, consisting of two parts, like the cap of a spring purse, the concave part outwards, each of which falls back with indented edges (like an iron spring fox-trap); upon anything touching the leaves, or falling between them, they instantly close like a spring trap, and confine any insect or anything that falls between them. It bears a white flower. To this surprising plant I have given the name of Fly trap Sensitive.

This was the first detailed recorded notice of the plant by Europeans. The description was before John Ellis' letter to The London Magazine on 1 September 1768, and his letter to Carl Linnaeus on 23 September 1768, in which he described the plant and proposed its English name Venus's Flytrap and scientific name Dionaea muscipula.

Description

The Venus flytrap is a small plant whose structure can be described as a rosette of four to seven leaves, which arise from a short subterranean stem that is actually a bulb-like object. Each stem reaches a maximum size of about three to ten centimeters, depending on the time of year; longer leaves with robust traps are usually formed after flowering. Flytraps that have more than seven leaves are colonies formed by rosettes that have divided beneath the ground.

The leaf blade is divided into two regions: a flat, heart-shaped photosynthesis-capable petiole, and a pair of terminal lobes hinged at the midrib, forming the trap which is the true leaf. The upper surface of these lobes contains red anthocyanin pigments and its edges secrete mucilage. The lobes exhibit rapid plant movements, snapping shut when stimulated by prey. The trapping mechanism is tripped when prey contacts one of the three hair-like trichomes that are found on the upper surface of each of the lobes. The mechanism is so highly specialized that it can distinguish between living prey and non-prey stimuli, such as falling raindrops; two trigger hairs must be touched in succession within 20 seconds of each other or one hair touched twice in rapid succession, whereupon the lobes of the trap will snap shut, typically in about one-tenth of a second. The edges of the lobes are fringed by stiff hair-like protrusions or cilia, which mesh together and prevent large prey from escaping. These protrusions, and the trigger hairs (also known as sensitive hairs) are likely homologous with the tentacles found in this plant's close relatives, the sundews. Scientists have concluded that the snap trap evolved from a fly-paper trap similar to that of Drosera.

The holes in the meshwork allow small prey to escape, presumably because the benefit that would be obtained from them would be less than the cost of digesting them. If the prey is too small and escapes, the trap will usually reopen within 12 hours. If the prey moves around in the trap, it tightens and digestion begins more quickly.

Speed of closing can vary depending on the amount of humidity, light, size of prey, and general growing conditions. The speed with which traps close can be used as an indicator of a plant's general health. Venus flytraps are not as humidity-dependent as are some other carnivorous plants, such as , Cephalotus, most Heliamphora, and some .

The Venus flytrap exhibits variations in petiole shape and length and whether the leaf lies flat on the ground or extends up at an angle of about 40-60 degrees. The four major forms are: 'typica', the most common, with broad decumbent petioles; 'erecta', with leaves at a 45-degree angle; 'linearis', with narrow petioles and leaves at 45 degrees; and 'filiformis', with extremely narrow or linear petioles. Except for 'filiformis', all of these can be stages in leaf production of any plant depending on season (decumbent in summer versus short versus semi-erect in spring), length of photoperiod (long petioles in spring versus short in summer), and intensity of light (wide petioles in low light intensity versus narrow in brighter light).

The plant also has a flower on top of a long stem, about 6 inches long. The flower is pollinated from various flying insects such as sweat bees, longhorn beetles and checkered beetles.

Flowering Venus flytrap showing its long flower stem

Closeup of flower ( c. 20 mm in diameter)

The species produces small, shiny black seeds

Habitat and distribution

The Venus flytrap is found in nitrogen- and phosphorus-poor environments, such as bogs, wet savannahs, and canebrakes. Small in stature and slow-growing, the Venus flytrap tolerates fire well and depends on periodic burning to suppress its competition. Fire suppression threatens its future in the wild. It survives in wet sandy and peaty soils. Although it has been successfully transplanted and grown in many locales around the world, it is native only to the coastal bogs of North and South Carolina in the United States, specifically within a 100-kilometer (60 mi) radius of Wilmington, North Carolina. One such place is North Carolina's Green Swamp. There also appears to be a naturalized population of Venus flytraps in northern Florida as well as an introduced population in western Washington. The nutritional poverty of the soil is the reason it relies on such elaborate traps: insect prey provide the nitrogen for protein formation that the soil cannot. They tolerate mild winters, and require a period of winter dormancy to survive freezing temperatures. It is a common misconception that Venus flytraps require dormancy if kept indoors or in warmer conditions.

They are full sun plants, usually found only in areas with less than 10% canopy cover. The habitats where it thrives are typically either too nutrient-poor for many noncarnivorous plants to survive, or frequently disturbed by fires which regularly clear vegetation and prevent a shady overstory from developing. It can be found living alongside herbaceous plants, grasses, sphagnum, and fire-dependent Arundinaria bamboos. Regular fire disturbance is an important part of its habitat, required every 3-5 years in most places for D. muscipula to thrive. After fire, D. muscipula seeds germinate well in ash and sandy soil, with seedlings growing well in the open post-fire conditions. The seeds germinate immediately without a dormant period.

Distribution

Dionaea muscipula occurs naturally only along the coastal plain of North and South Carolina in the U.S, with all known current sites within 90 km of Wilmington, North Carolina. A 1958 survey of herbaria specimens and old documents found 259 sites where the historical record documented the presence of D. muscipula, within 21 counties in North and South Carolina. As of 2019, it was considered extirpated in North Carolina in the inland counties of Moore, Robeson, and Lenoir, as well as the South Carolina coastal counties of Charleston and Georgetown. Remaining extant populations exist in North Carolina in Beaufort, Craven, Pamlico, Carteret, Jones, Onslow, Duplin, Pender, New Hanover, Brunswick, Columbus, Bladen, Sampson, Cumberland, and Hoke counties, and in South Carolina in Horry county.

Population

A large-scale survey in 2019, conducted by the North Carolina Natural Heritage Program, counted a total of 163,951 individual Venus flytraps in North Carolina and 4,876 in South Carolina, estimating a total of 302,000 individuals remaining in the wild in its native range. This represents a reduction of more than 93% from a 1979 estimate of approximately 4,500,000 individuals. A 1958 study found 259 confirmed extant or historic sites. As of 2016, there were 71 known sites where the plant could be found in the wild. Of these 71 sites, only 20 were classified as having excellent or good long-term viability.

Prey selectivity

Most carnivorous plants selectively feed on specific prey. This selection is due to the available prey and the type of trap used by the organism. With the Venus flytrap, prey is limited to beetles, spiders and other crawling arthropods. The Dionaea diet is 33% ants, 30% spiders, 10% beetles, and 10% grasshoppers, with fewer than 5% flying insects.

Given that Dionaea evolved from an ancestral form of Drosera (carnivorous plants that use a sticky trap instead of a snap trap) the reason for this evolutionary branching becomes clear. Drosera consume smaller, aerial insects, whereas Dionaea consume larger terrestrial bugs. Dionaea are able to extract more nutrients from these larger bugs. This gives Dionaea an evolutionary advantage over their ancestral sticky trap form.

Mechanism of trapping

The Venus flytrap is one of a very small group of plants capable of rapid movement, such as Mimosa pudica, the Telegraph plant, starfruit, sundews and bladderworts.

The mechanism by which the trap snaps shut involves a complex interaction between elasticity, turgor and growth. The trap only shuts when there have been two stimulations of the trigger hairs; this is to avoid inadvertent triggering of the mechanism by dust and other wind-borne debris. In the open, untripped state, the lobes are convex (bent outwards), but in the closed state, the lobes are concave (forming a cavity). It is the rapid flipping of this bistable state that closes the trap, but the mechanism by which this occurs is still poorly understood. When the trigger hairs are stimulated, an action potential (mostly involving calcium ions-see calcium in biology) is generated, which propagates across the lobes and stimulates cells in the lobes and in the midrib between them.

It is hypothesized that there is a threshold of ion buildup for the Venus flytrap to react to stimulation. The acid growth theory states that individual cells in the outer layers of the lobes and midrib rapidly move ( hydrogen ions) into their cell walls, lowering the pH and loosening the extracellular components, which allows them to swell rapidly by osmosis, thus elongating and changing the shape of the trap lobe. Alternatively, cells in the inner layers of the lobes and midrib may rapidly secrete other ions, allowing water to follow by osmosis, and the cells to collapse. Both of these mechanisms may play a role and have some experimental evidence to support them. Flytraps show an example of memory in plants; the plant knows if one of its trigger hairs have been touched, and remembers this for a few seconds. If a second touch occurs during that time frame, the flytrap closes. After closing, the flytrap counts additional stimulations of the trigger hairs, to five total, to start the production of digesting enzymes.

If the prey is unable to escape, it will continue to stimulate the inner surface of the lobes, and this causes a further growth response that forces the edges of the lobes together, eventually sealing the trap hermetically and forming a "stomach" in which digestion occurs. Release of the digestive enzymes is controlled by the hormone jasmonic acid, the same hormone that triggers the release of toxins as an anti-herbivore defense mechanism in non-carnivorous plants. (See Evolution below) Once the digestive glands in the leaf lobes have been activated, digestion is catalysed by hydrolase enzymes secreted by the glands. One of these enzymes includes GH18 chitinase, which breaks down chitin-containing exoskeleton of trapped insects. Synthesis of this enzyme begins with at least five action potentials, which will stimulate transcription of chitinase.

Oxidative protein modification is likely to be a pre-digestive mechanism used by Dionaea muscipula. Aqueous leaf extracts have been found to contain quinones such as the naphthoquinone plumbagin that couples to different NADH-dependent diaphorases to produce superoxide and hydrogen peroxide upon autoxidation. Such oxidative modification could rupture animal cell membranes. Plumbagin is known to induce apoptosis, associated with the regulation of the Bcl-2 family of proteins. When the Dionaea extracts were pre-incubated with diaphorases and NADH in the presence of serum albumin (SA), subsequent tryptic digestion of SA was facilitated. Since the secretory glands of Droseraceae contain proteases and possibly other degradative enzymes, it may be that the presence of oxygen-activating redox cofactors function as extracellular pre-digestive oxidants to render membrane-bound proteins of the prey ( insects) more susceptible to proteolytic attacks.

Digestion takes about ten days, after which the prey is reduced to a husk of chitin. The trap then reopens, and is ready for reuse.

Carnivory in plants is a very specialized form of foliar feeding, and is an adaptation found in several plants that grow in nutrient-poor soil. Carnivorous traps were naturally selected to allow these organisms to compensate for the nutrient deficiencies of their harsh environments and compensate for the reduced photosynthetic benefit. Phylogenetic studies have shown that carnivory in plants is a common adaptation in habitats with abundant sunlight and water but scarce nutrients. Carnivory has evolved independently six times in the angiosperms based on extant species, with likely many more carnivorous plant lineages now extinct.

The "snap trap" mechanism characteristic of Dionaea is shared with only one other carnivorous plant genus, Aldrovanda. For most of the 20th century, this relationship was thought to be coincidental, more precisely an example of convergent evolution. Some phylogenetic studies even suggested that the closest living relatives of Aldrovanda were the sundews. It was not until 2002 that a molecular evolutionary study, by analyzing combined nuclear and chloroplast DNA sequences, indicated that Dionaea and Aldrovanda were closely related and that the snap trap mechanism evolved only once in a common ancestor of the two genera.

A 2009 study presented evidence for the evolution of snap traps of Dionaea and Aldrovanda from a flypaper trap like Drosera regia, based on molecular data. The molecular and physiological data imply that Dionaea and Aldrovanda snap traps evolved from the flypaper traps of a common ancestor with . Pre-adaptations to the evolution of snap traps were identified in several species of Drosera, such as rapid leaf and tentacle movement. The model proposes that plant carnivory by snap trap evolved from the flypaper traps, driven by increasing prey size. Bigger prey provides greater nutritional value, but large insects can easily escape the sticky mucilage of flypaper traps; the evolution of snap traps would therefore prevent escape and kleptoparasitism (theft of prey captured by the plant before it can derive benefit from it), and would also permit a more complete digestion.

In 2016, a study of the expression of genes in the plant's leaves as they captured and digested prey was published in the journal, Genome Research. The gene activation observed in the leaves of the plants gives support to the hypothesis that the carnivorous mechanisms present in the flytrap are a specially adapted version of mechanisms used by non-carnivorous plants to defend against herbivorous insects. In many non-carnivorous plants, jasmonic acid serves as a signaling molecule for the activation of defense mechanisms, such as the production of hydrolases, which can destroy chitin and other molecular components of insect and microbial pests. In the Venus flytrap, this same molecule has been found to be responsible for the activation of the plant's digestive glands. A few hours after the capture of prey, another set of genes is activated inside the glands, the same set of genes that is active in the roots of other plants, allowing them to absorb nutrients. The use of similar biological pathways in the traps as non-carnivorous plants use for other purposes indicates that somewhere in its evolutionary history, the Venus flytrap repurposed these genes to facilitate carnivory.

Proposed evolutionary history

Carnivorous plants are generally herbaceous, and their traps the result of primary growth. They generally do not form readily fossilizable structures such as thick bark or wood. As a result, there is no fossil evidence of the steps that might link Dionaea and Aldrovanda, or either genus with their common ancestor, Drosera. Nevertheless, it is possible to infer an evolutionary history based on phylogenetic studies of both genera. Researchers have proposed a series of steps that would ultimately result in the complex snap-trap mechanism:

Larger insects usually walk over the plant, instead of flying to it, and are more likely to break free from sticky glands alone. Therefore, a plant with wider leaves, like Drosera falconeri, must have adapted to move the trap and its stalks in directions that maximized its chance of capturing and retaining such prey-in this particular case, longitudinally. Once adequately "wrapped", escape would be more difficult.

Evolutionary pressure then selected for plants with shorter response time, in a manner similar to Drosera burmannii or Drosera glanduligera. The faster the closing, the less reliant on the flypaper model the plant would be.

As the trap became more and more active, the energy required to "wrap" the prey increased. Plants that could somehow differentiate between actual insects and random detritus/rain droplets would have an advantage, thus explaining the specialization of inner tentacles into trigger hairs.

Ultimately, as the plant relied more on closing around the insect rather than gluing them to the leaf surface, the tentacles so evident in Drosera would lose their original function altogether, becoming the "teeth" and trigger hairs-an example of natural selection utilizing pre-existing structures for new functions.

Completing the transition, the plant eventually developed the depressed digestive glands found inside the trap, rather than using the dews in the stalks, further differentiating it from genus Drosera.

Phylogenetic studies using molecular characters place the emergence of carnivory in the ancestors of Dionaea muscipula to 85.6 million years ago, and the development of the snap-trap in the ancestors of Dionaea and its sister genus Aldrovanda to approximately 48 million years ago.

Cultivation

Plants can be propagated by seed, taking around four to five years to reach maturity. More commonly, they are propagated by clonal division in spring or summer. Venus flytraps can also be propagated in vitro using plant tissue culture. Most Venus flytraps found for sale in nurseries garden centers have been produced using this method, as this is the most cost-effective way to propagate them on a large scale. Regardless of the propagation method used, the plants will live for 20 to 30 years if cultivated in the right conditions.

Venus flytraps are by far the most commonly recognized and cultivated carnivorous plant, and they are frequently sold as houseplants. Various cultivars (cultivated varieties) have come into the market through tissue culture of selected genetic mutations, and these plants are raised in large quantities for commercial markets. The cultivars 'Akai Ryu and 'South West Giant' have gained the Royal Horticultural Society's Award of Garden Merit.

Conservation

Although widely cultivated for sale as a houseplant, D. muscipula has suffered a significant decline in its population in the wild. The population in its native range is estimated to have decreased 93% since 1979.

The species is under Endangered Species Act review by the U.S. Fish & Wildlife Service. The current review commenced in 2018, after an initial "90-day" review found that action may be warranted. A previous review in 1993 resulted in a determination that the plant was a "Potential candidate without sufficient data on vulnerability". The IUCN Red List classifies the species as "vulnerable". The State of North Carolina lists Dionaea muscipula as a species of "Special Concern-Vulnerable". The species is protected under Appendix II of the Convention on International Trade in Endangered Species (CITES) meaning international trade (including in parts and derivatives) is regulated by the CITES permitting system. NatureServe classified it as "Imperiled" (G2) in a 2018 review.

The U.S. Fish and Wildlife Service has not indicated a timeline to conclude its current review of Dionaea muscipula. The Endangered Species Act specifies a two-year timeline for a species review. However, the species listing process takes 12.1 years on average.

The Venus flytrap is only found in the wild in a very particular set of conditions, requiring flat land with moist, acidic, nutrient-poor soils that receive full sun and burn frequently in forest fires, and is therefore sensitive to many types of disturbance. A 2011 review identified five categories of threats for the species: agriculture, road-building, biological resource use (poaching and lumber activities), natural systems modifications (drainage and fire suppression), and pollution (fertilizer).

Habitat loss is a major threat to the species. The human population of the coastal Carolinas is rapidly expanding. For example, Brunswick County, North Carolina, which has the largest number of Venus flytrap populations, has seen a 27% increase in its human population from 2010 to 2018. As the population grows, residential and commercial development and road building directly eliminate flytrap habitat, while site preparation that entails ditching and draining can dry out soil in surrounding areas, destroying the viability of the species. Additionally, increased recreational use of natural areas in populated areas directly destroys the plants by crushing or uprooting them.

Fire suppression is another threat to the Venus flytrap. In the absence of regular fires, shrubs and trees encroach, outcompeting the species and leading to local extirpations. D. muscipula requires fire every 3-5 years, and best thrives with annual brush fires. Although flytraps and their seeds are typically killed alongside their competition in fires, seeds from flytraps adjacent to the burnt zone propagate quickly in the ash and full sun conditions that occur post a fire disturbance. Because the mature plants and new seedlings are typically destroyed in the regular fires that are necessary to maintain their habitat, D. muscipula' s survival relies upon adequate seed production and dispersal from outside the burnt patches back into the burnt habitat, requiring a critical mass of populations, and exposing the success of any one population to metapopulation dynamics. These dynamics make small, isolated populations particularly vulnerable to extirpation, for if there are no mature plants adjacent to the fire zone, there is no source of seeds post-fire.

Poaching has been another cause of population decline. Harvesting Venus flytraps on public land became illegal in North Carolina in 1958, and since then a legal cultivation industry has formed, growing tens of thousands of flytraps in commercial greenhouses for sale as household plants. Yet in 2016, the New York Times reported that demand for wild plants still exists, which "has led to a 'Venus flytrap crime ring.'" In 2014, the state of North Carolina made Venus flytrap poaching a felony. Since then, several poachers have been charged, with one man receiving 17 months in prison for poaching 970 Venus flytraps, and another man charged with 73 felony counts in 2019. Poachers may do greater harm to the wild populations than a simple count of individuals taken would indicate, as they may selectively harvest the largest plants at a site, which have more flowers and fruit and therefore generate more seeds than smaller plants.

Additionally, the species is particularly vulnerable to catastrophic climate events. Most Venus flytrap sites are only 2-4 meters (6.5 -13 feet) above sea level and are located in a region prone to hurricanes, making storm surges and rising sea levels a long-term threat.

Designations

In 2005, the Venus flytrap was designated as the state carnivorous plant of North Carolina.

In alternative medicine

Venus flytrap extract is available on the market as an herbal remedy, sometimes as the prime ingredient of a patent medicine named "Carnivora". According to the American Cancer Society, these products are promoted in alternative medicine as a treatment for a variety of human ailments including HIV, Crohn's disease and skin cancer, even though available scientific evidence does not support these health claims.

In Spanish: Dionaea muscipula para niños