Evolution by John Oskanian

Evolution by John Oskanian https://padlet.com/jo792/kwvlvd8pt0ko Made with magic en-us 2017-05-26 16:57:00 UTC 2025-09-24 06:23:13 UTC hello@padlet.com https://padlet-assets.s3.amazonaws.com/icons/File.png Characteristics of Taxonomic Group jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174025117 Some examples of marsupials include: Kangaroos, Koalas, and Opossums. Some physical characteristics shared by marsupials are:

Females carry their young in pouches
They are nursed until early infancy
They are native to Australia, Tasmania, New Guinea, and the Americas
All marsupials contain fur
Marsupials have less energy requirements than placental mammals

Behavioral characteristics:

Most marsupials live in small groups, Most marsupials are not aquatic, They communicate using acoustic signals and they have color patterns that convey information about sex

]]> 2017-05-26 17:15:21 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174025117 Exemplary Organism 1 jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174109154 Common name: Kangaroo

Location & habitat : They are found in the deserts, savannas, and grassy plains of Australia
Physical characteristics (internal & external):

Female kangaroos carry pouches for their young
All kangaroos have strong hind legs with extended feet and short forelegs
They have strong backbones
They are known for their capability to jump long distances

Behavioral characteristics:

They are grazing herbivores, which means their diet consists mainly of grasses
They live in groups of 2-4 kangaroos
They are unique from other marsupials because they are the only large marsupial to use hopping as a way of moving

Taxonomy (Red Kangaroo):
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Diprotodontia
Family: Macropodidae
Genus: Macropus
Species: rufus

]]> 2017-05-28 01:12:54 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174109154 Exemplary Organism 2 jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174109964 Common name: Opossum

Location & habitat: They live in trees of North America and Australia, but the most common location in North America is Virginia
Physical characteristics (internal & external):

They have gray fur and white faces
Females have pouches for their young
Opossums are the only animal in the U.S that have prehensile tails, which means they are able to grasp objects with their tail
They are the only mammals that contain 4 fingers and opposable thumbs on their hind feet

Behavioral characteristics:

They play “dead” to avoid being eaten by other predators
They eat anything they can catch
They usually give birth 2 weeks after they mate

Taxonomy (Virginia Opossum):
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Didelphimorphia
Family: Didelphidae
Genus: Didelphis
Species: virginiana

]]> 2017-05-28 01:59:22 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174109964 Exemplary Organism 3 jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174110862 Common name: Koala Bear

Location & habitat: Most koalas do not live in rainforests or deserts, they live in low eucalypt forests in eastern Australia
Physical characteristics (internal & external):

They have thick fur to protect them from high or low temperatures
They are warm blooded
They have grey fur and an appearance similar to a teddy bear

Behavioral characteristics:

They sleep for up to 16 hours a day in trees, most prefer to be alone
They are great swimmers
They are able to climb from one branch to another quickly
They growl to scare off aggressors

Taxonomy:
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Diprotodontia
Family: Phascolarctidae
Genus: Phascolarctos
Species: cinereus

]]> 2017-05-28 02:40:42 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174110862 Anatomy and Physiology jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174166777 Anatomy:

Marsupials have skulls that are small and tight
Marsupials have 40 to 50 teeth
Female marsupials have a pouch where the offspring continue to develop after being born

Physiology:

Koalas eat eucalyptus leaves, which have a poison. The digestive system of a koala is able to detoxify the poison carried in the leaves. There are over 600 types of eucalyptus trees in Australia, but koalas eat leaves from only a few. Most koalas eat leaves from only one or two types of trees.
Opossums are omnivores. Their main diet features insects, rodents, and garbage
Kangaroos are herbivores. Their main diet consists of grass, flowers, mosses, and leaves

]]> 2017-05-28 23:16:56 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174166777 Marsupial Phylogenetic Tree jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174168866 2017-05-28 23:51:27 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174168866 Embryology jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174174029 Kangaroo Development:

A Kangaroo's gestational period is short and lasts about 26 days
The limb development for baby kangaroos is a long, ongoing process
A baby kangaroo's immune system, thermoregulation, and thyroid develop after birth

Koala Development:

Male koalas mature at 3 years old, while females mature at 2 to 3 years old
Baby koalas usually stay in their mother's pouch for 6 months
When the baby koalas come out of their mother's pouch, they begin to explore
A Koala joey weighs 1 gram when it is born

Opossum Development:

The young are basically embryos at birth
After they are born, they use a swimming motion up to the mother's teat to latch on to it
Like other marsupials, the young must be born early in their development

]]> 2017-05-29 01:13:23 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174174029 Darwin's Theories of Evolution jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174284926
One of Darwin's theories of evolution is Natural Selection. Natural Selection means that the organisms that adapt better to their environment survive and reproduce more than organisms that aren't well adapted to their environment. Natural Selection helps bring about evolution. Another one of Darwin's theories of evolution is descent with modification, this means that the traits the present-day marsupials have are passed down from generation to generation. Both of these theories are present in modern marsupials. Sthenurine kangaroos went extinct because they did not have the trait to hop away from predators. Instead, all they could do was walk and thus did not survive faster predators.

]]> 2017-05-29 18:07:12 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174284926 Chromosomal Analysis jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174469307 Grey kangaroos have 16 chromosomes (8 pairs), except for red kangaroos, who have 20 chromosomes (10 pairs). Koalas have 16 chromosomes and opossums have 22 chromosomes (11 pairs). The grey kangaroo and koala are related because they both have the same number of chromosomes and they both have the same fur color. Their karyotypes are different from a human's karyotype because they have a different number of chromosomes. However, they are similar to a human karyotype because marsupials and humans have one pair of sex chromosomes

]]> 2017-05-30 17:31:18 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174469307 DNA in Marsupials jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174525014 Many marsupials share some DNA since they evolved from a common ancestor. Most marsupials are found in Australia. Some are found in North America, like the opossum due to genetic drift. Examples of how they share some of the same DNA are the traits they have in common such as females having pouches. Most marsupials also have grey fur and long tails.]]> 2017-05-31 00:39:12 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174525014 Conclusion Statements jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174667980 Speciation:
The type of speciation marsupials have is gradual equilibrium because it took a long time for marsupials to evolve into what they are today

Type of Evolution:
The type of evolution marsupials went through is divergent evolution. One example of divergent evolution occurring is the koala and the kangaroo because they are both marsupials but have different traits which enable them to survive in their different niches, koalas in trees, and kangaroos on Savannah

Genetic Drift:
Genetic drift occurred in marsupials because the extinct kangaroos had some genes that didn't get passed down on to future generations, as a result of sampling error. For example, the extinct kangaroos had rabbit-like faces that the present-day kangaroos do not have. Also genetic drift is more pronounced in small populations; most kangaroos live in groups of 2-4

Geographic Isolation:
Geographic isolation affected marsupials after the breakup of Pangea which started millions of years ago. The breakup of Pangea resulted in separation of South America, Antarctica, and Australia from each other. Marsupials had been present in all three continents but thrived in Australia because their life cycle was well suited to Australia's dry climate and poor soil quality. This is because marsupials have a lower metabolic rate than placentals, and marsupials have less need for energy than placentals
In addition, some marsupials that are living in the Americas immigrated across Pangea to present-day North and South America

]]> 2017-05-31 17:12:25 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174667980 Fossil #1 jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174893629 2017-06-01 22:28:49 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174893629 Fossil #2 jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174894619 2017-06-01 22:42:06 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174894619 Fossil #3 jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174894683 2017-06-01 22:42:54 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174894683 Fossil #4 jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174894940 2017-06-01 22:46:20 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174894940 Fossil #5 jo792 https://padlet.com/jo792/kwvlvd8pt0ko/wish/174898551 2017-06-01 23:37:37 UTC https://padlet.com/jo792/kwvlvd8pt0ko/wish/174898551