https://padlet.com/ap554/ar4iu60pmb0m en-us 2018-05-30 17:54:11 UTC 2025-12-24 13:08:15 UTC hello@padlet.com ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/264604779 Order Pinnipedia]]> 2018-05-30 17:58:31 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/264604779 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/264605913 Internal/External

1.  All have four webbed flippers used to propel their bodies
2.  All have canine teeth and molars that are used to consume their prey
3.  All have large eyes and well developed whiskers for finding food in dim water
4.  All of their tails are small which limits their drag

Behavioral

1. Pinnipeds mate and can give birth on land, ice, or in shallow water and nurse their young on land. Most females usually do not eat when nursing and live off of their fat and blubber
2. Adult male pinnipeds compete with each other when mating and these competitions can result in physical scars/harm
3. Pinnipeds have strong navigational capabilities 
4. When feeding, they can eat any type of food they can find in the water such as squid, octopus, and shellfish. Their flippers are used to get around in the water while feeding and to navigate

Habitat

1. Pinnipeds are found in aquatic habitats such as the open ocean, costal waters, and freshwater lakes and rivers. 
2. They also haul out on land to reproduce, mate, and some nurse their young on land
3. Pinnipeds usually haul out on sandy beaches, pebble beaches, rocky shores, and tide pools
4. They travel offshore to feed off of oceanic islands 

https://seagrant.uaf.edu/marine-ed/mm/fieldguide/pinnipeds.html

https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/pinniped
http://www.marinemammalcenter.org/education/marine-mammal-information/pinnipeds/

]]> 2018-05-30 18:02:54 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/264605913 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/264607073 1. Pacific Walrus
2. Northern Fur Seal (Eared)
3.Grey Seal (Earless) ]]> 2018-05-30 18:07:14 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/264607073 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/264608121 Location & Habitat

• Pacific Walruses live where the temperature is 5-41 degrees F
• They are found where the water is 262 ft deep 
  • Two-thirds of a walrus's life is spent in the water
  • Spend the summer floating on ice 
• They have adapted to living in a habitat of sea ice and snow
• Walrus's come onto shore when the water in their habitat is too deep

Physical Characteristics

• Male walrus weight- 1,764 to 3,748 lbs, 9 to 12 ft long
• Female walrus weight- 882 to 2,756 lbs, 7.5 to 10 ft long
• Walruses have a spindle shaped body
• Cinnamon brown body color
  • Appear pale underwater
• Calves at birth are light brown (almost grey) but become browner as they grow and their bodies develop
• Their limbs are adapted as flippers; flippers are hairless
  • The skin on the flippers is rough and thick which provides traction on land
• Each of the walrus's flippers have 5 digits all equal in length
  • Each digit has a claw

Behavioral Characteristics

• Walrus tusks are used as weapons 
  • A walrus can achieve dominance over another walrus by the tusk size and the aggressivness displayed
  • Males will fight each other and usually results in physical injuries 
• Walruses are very social 
  • They are one of the most social animals
• Males and females are in separate herds
• Male walruses make a sound similar to a bell to display courtship to attract other women
• They also haul out on land/ice to rest and care for their young 
  • They uses their tusks to do this 

https://seaworld.org/en/animal-info/animal-infobooks/walrus/reproduction
https://www.worldwildlife.org/magazine/issues/summer-2017/articles/walrus-habitat-on-the-edge

]]> 2018-05-30 18:23:46 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/264608121 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/264628358 Location & Habitat

• Northern Fur Seals in the open ocean where they frequently search for beaches to reproduce
  • They are rarely seen on the mainland unless they are sick or breeding
  • Adult fur seals spend over 300 days a year foraging (searching for beaches to reproduce)
  • There are large groups of fur seals located on seamounts, canyons valleys, and on the continental shelf break
    • There is a high availability of prey in the continental shelf
  • The North Pacific Transition Zone is an important region for reproduction 
  • Seals haul out on broad sandy beaches

Physical Characteristics

• Northern Fur Seals have a very wide range of weight
  • They range from 120-600 lbs
  • Males weigh 300-650 lbs
  • Females weigh 90-110 lbs
• They are typically 5-7 ft long
• Male fur seals fur color is grey or black
• Female fur seals fur color is light grey on their back and reddish brown on their chest with a light patch
• Fur seals have a stocky body, small head, a and short snout
• They have very dense fur 
  • The cold water from the ocean does not touch their skin which preserves their body heat
  • But their fur is not waterproof
• They have large hairless flippers which also keep them cool
• Fur seals rotate their flippers forward so they can walk, run, and climb out of the water when they need to

Behavioral Characteristics

• Northern Fur Seals are usually found feeding on squid, anchovy, herring, walleye pollock, and hake in the open ocean
  • They are not deep divers and do not go deep into the water to find their food
• Since they are found in the open ocean they do not haul out on land, like walruses, to rest
• They also "jug handle"
  • Fur seals keep their rear flippers out of the water while bobbing on the surface of the ocean
• Males also have an early breeding season which starts in May

https://www.seals-world.com/seal-social-structure/
http://www.nmfs.noaa.gov/pr/species/mammals/seals/northern-fur-seal.html

http://www.marinemammalcenter.org/education/marine-mammal-information/pinnipeds/northern-fur-seal/

]]> 2018-05-30 20:12:56 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/264628358 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/264797013 Location & Habitat

• Grey Seals are generally found in coastal waters 
• They survive in a cold water habitat
  • They will uses their blubber to keep warm
• They occupy rocky coasts, islands, sandbars, ice shelves, and icebergs
• Grey seals are located in the Western North Atlantic Stock
  • Located in eastern Canada and eastern US
• They are also located in the Eastern North Atlantic Stock
  • Located in Britain, Iceland, Norway, Denmark, Faroe Islands, and the Russian Baltic Sea Stock
• Largest native mammal in the British Isles

Physical Characteristics

• Grey seal pups are born with white fur 
  • Females have a grayish silver fur coat with some dark spots 
  • Males have a dark grey coat with silver grey spots 
• Their coats are very dense coats that end at their flippers 
  • Males also have an arched long nose, unlike females 
• They have a stocky, small body and females have a short snout
• They weigh 130-600 lbs
  • Males weigh more than females
• These seals are 5-7 ft long 
  • Males are also longer than females
• Males can grow to 7 ft long and weigh 600 lbs
• Male grey seals also have longer necks, shoulders, and chest than female grey seals
• Their hind flippers are also one-fourth of their body weight 
• Grey seals are also eared seals 

Behavioral Characteristics

• Grey seals gather into large groups for breeding and to care for their pups
  • They also gather in large groups to rest on land
• Males and females do not eat during their 4-6 week breeding period 
  • They use their fat from their blubber for nutrition
• Males who spend more time chasing females on land have a better chance of mating
  • Males also compete with other males seals for access to females 
• Grey seals usually dive alone or in small groups when they are finding food

http://animaldiversity.org/accounts/Halichoerus_grypus/

https://animalcorner.co.uk/animals/grey-seal/

]]> 2018-05-31 14:19:39 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/264797013 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/264860843 Anatomy of the pinnipeds

• The pinniped families have evolved to fit their needs in the water, on land, finding food, and reproducing
• Pinnipeds started off as organisms with the sequence 1 bone, 2 bones, many bones, falangees
• They also had fingers that were closer together and short in lenght
  • Their heads were also flat and rounded for the ability to glide in the water 
• They also had short front teeth chewing and breaking down their food and biting their prey
• Over time, pinnipeds' flippers have developed and curved to help them swim in the water and haul out on land
  • As pinnipeds have evolved, their flippers have become more curved and their fingers have become more spread out for more grip on land when they haul out
• The walrus, Odebenids, also has more of a curved front head/jaw because of its tusks
  • They uses their tusks for hauling their bodies out on land, hunting, and defense unlike the eared seal and earless seal
• Pinnipeds also have similar shaped femur bones which they use for mobility of the flippers and stability while on land/when hauling out for breeding, nursing their young, or hunting

http://palaeo.gly.bris.ac.uk/Palaeofiles/Pinnipeds/evolution.html

]]> 2018-05-31 18:11:55 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/264860843 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265114767

Pinnipeds all have a similar number of chromosomes 

Otariids have 2n=36 diploid chromosomes; a total of 18 pairs of chromosomes

Odebenids have 2n=32 chromosomes; a total of 16 pairs of chromosomes

Phocidae have chromosomes numbers ranging from 2n=34 to 2n=32; a total of either 16 or 17 pairs of chromosomes

These chromosome numbers show how closely related these organisms are because they have a range of 32 to 36 total diploid cells

Also in their karyotypes, the centromeres are almost exactly in the same place and the banding patterns are very similar in structure

This evidence can show how the structure of these species chromosomes are very similar in each of these organisms' karyotypes 

• In addition, having similar numbers of diploid chromosomes, very few differences in their chromosome numbers, and similar karyotypes supports the fact that these species are related

]]> 2018-06-01 23:16:51 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265114767 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265115143 2018-06-01 23:27:23 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265115143 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265115182 2018-06-01 23:28:30 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265115182 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265115227 2018-06-01 23:29:35 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265115227 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265115279 2018-06-01 23:31:05 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265115279 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265115305

This phylogenic tree shows the connection between the family Otariidae, Odobenidae, and Phocidae. 

There was a common ancestor which connected all of the species together 

All of these species have "risen" from this one common ancestor that they all share at the bottom of the tree trunk

There is an evolutionary relationship between those three speices 

These three species are very close in distance which shows how closely related they all are 

The most recent common ancestor is shared between all three of these organisms because they form a "triangle" shape and shows that they are the most closely related organisms in this tree

Walruses and eared seals evolved from a bear ancestor and the true seals evolved from an otter carnivore

The tree shows that all pinnipeds have evolved from a monophyletic group

Walruses share a closer relationship with earless seals (Phocidae) than with eared seals (Otaridae)

http://what-when-how.com/marine-mammals/pinniped-evolution-marine-mammals/
http://palaeo.gly.bris.ac.uk/Palaeofiles/Pinnipeds/evolution.html

]]> 2018-06-01 23:31:49 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265115305 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265151083

Name of fossil: Chin of Pelagiarctos thomasi; Age: 700,000 years old

Name of fossil: Skull of Allodesmus kelloggi; Age: 15-17 million years old

Name of fossil: Skull of the modern day female Callorhinus ursinus; Age: 22-25 Ma

Name of the fossil: Femora of the Oligocene; Age: 45-49 Ma in age.

Name of fossils: Jaws and teeth of many different pinnipeds; Ages: Dated back to 15-27 Ma

http://coastalpaleo.blogspot.com/search/label/pinnipedia

]]> 2018-06-02 14:02:45 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265151083 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265151428 2018-06-02 14:09:38 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265151428 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265151810 2018-06-02 14:16:18 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265151810 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265151942 2018-06-02 14:18:31 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265151942 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265152133 2018-06-02 14:21:37 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265152133 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265158909 2018-06-02 16:16:16 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265158909 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265158963 2018-06-02 16:17:27 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265158963 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265159041 2018-06-02 16:19:17 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265159041 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265160621 Gradual Speciation

• Pinnipeds have gradually diverged over time and have developed different characteristics for the needs of that organism throughout its evolutionary history
• Small changes have occurred in the earless seal, eared seal, and the walrus as time has passed 
• Each organism developed traits to help them survive in their specific environment and to continue to reproduce
• The needs of each organism are very different so they each have changed and evolved from the one common ancestor that they all shared 

Sympatric Speciation

• Pinnipeds have gone through sympatric speciation because they have shared the same type of habitat but have become reproductively isolated so that if each group tried to mate with one another, they will not produce fertile offspring; which leads to the further divergence of each group of organisms
• New species have evolved from a common ancestral species that were located in the same region and have shared the same habitat

http://www.yourarticlelibrary.com/biology/mechanisms-of-speciation-gradual-speciation-and-abrupt-of-instantaneous-speciation/27223

]]> 2018-06-02 16:52:30 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265160621 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265160782 Divergent Evolution

• Over time, Pinnipeds have become more and more dissimilar in their internal and external characteristics
• Pinnipeds have evolved from a common ancestor but have become different species over time
• The pinnipeds phylogenic tree shows how all of the pinnipeds have evolved from one ancestor
  • They all have developed different external characteristics that help each of them individually 
• For example, their head shapes have become different over time because they all have different characteristics
  • The walrus has a more roundish-square head because of its need for tusks 
  • Earless seals have a round head because they do not have ears and have an arched snout
  • Eared seals have a spindle shaped head because they have ears 
• Also, their flippers have changed over time to become more curved for their functional needs
  • The earless seal has the most curved flippers out of all three of these organisms because they extend backward and cannot be brought underneath their bodies 
• All pinnipeds have evolved from one common ancestor but have become very different structurally over time which supports the fact that they went through divergent evolution

http://what-when-how.com/marine-mammals/pinniped-evolution-marine-mammals/

]]> 2018-06-02 16:55:24 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265160782 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265160856 2018-06-02 16:56:30 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265160856 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265161030 Descent with Modification

• Newer species of Pinnipeds, Otarids, Odebenids, and Phocids, have become modified descendants of their ancestral species
• These similar species show different characteristics in their different habitats and locations
• Each generation of pinnipeds sexually reproduced which created a mixing of genes from the parents which creates genetic variation in the common ancestors descendants
• There is a change in the gene frequency in each generation which causes variation in the offspring of each generation
• Pinnipeds' DNA has changed over time in each generation. Their nucleotide sequence has evolved as time has went on and since each organism has developed from their ancestral species

Directional Selection

• Pinniped species have evolved through directional selection because different phenotypes have been favored over the pinnipeds evolutionary history to bring about new traits and help them survive 
• There have been many new phenotypes and physical characteristics that have occurred in pinnipeds
  • For example environmental factors have contributed to they  way pinnipeds have evolved
  • Walruses have the phenotype, or expressed physical characteristic, for their tusk size 
  • Earless seals have the phenotype for longer phalanges and curved flippers for mobility in the water and stabilization in the environment that they live in
  • Eared seals have the phenotype for straighter flippers and shorter phalanges so they can stand up on rocks when they haul out on land
• Natural selection has favored the phenotypes in the pinnipeds who have survived throughout their evolutionary history and this has caused a change in which traits are favored in each organism

https://biologydictionary.net/directional-selection/
https://sciencing.com/difference-between-natural-selection-descent-modification-17942.html

]]> 2018-06-02 16:59:40 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265161030 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265161825 2018-06-02 17:15:27 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265161825 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265161884 2018-06-02 17:16:30 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265161884 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265161947 2018-06-02 17:17:49 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265161947 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265162215

]]> 2018-06-02 17:22:28 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265162215 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265162237

This peptide sequence chart that compares the walrus, eared seals, and earless seals (at the bottom of the chart) shows the similarities in the protein sequence of these two organisms 

• This chart shows the amino acid sequence in both of these organisms and how each chain is very similar in structure

The walrus, eared, and earless seals have very similar and almost identical amino acid sequences which supports the fact that they are very similar and have evolved from each other 

• When there are many amino acids that are the same, that means their DNA sequences are also very similar
• DNA also codes for for the building of proteins

The amino acid sequences are determined by the nucleotide sequences in the DNA and since the walrus, eared, and earless seal have similar amino acids, their DNA and nucleotide sequences have to also be similar

There are a few differences in each of the organisms protein sequence but overall the sequences are similar proving that these three organisms are closely related

]]> 2018-06-02 17:22:53 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265162237 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265211222 Microevolution

• Microevolution has occurred in pinnipeds due to allele frequencies that have changed over time and how directional selection has occurred over time as well
• Over time, newer species of pinnipeds have evolved from the common ancestral species
  • The changes in each species is due to microevolution which lead to macroevolution which has emerged new species over time
• Genetic Drift has also resulted in the evolution of these organisms because there have been changed in the allele frequencies within the pinnipeds 
• In addition, population bottleneck has occurred in the grey seal and the harbor seal which has drastically reduced the size of these two organisms populations
  • There has been a decrease in genetic diversity/variation in these pinnipeds because of genetic drift within the pinniped populations 
• Also, population bottlenecks and nonrandom mating has occurred within the New Zealand Sea Lion population which has impacted the genetic variation
  • This sea lion has had a reduced population size and there has been an increase in interbreeding which has affected their long-term chance for survival

http://legacy.hopkinsville.kctcs.edu/instructors/jason-arnold/vli/module3evolution/Module3Evolution4.html
https://academic.oup.com/jhered/article/107/5/392/2622901

]]> 2018-06-03 13:57:29 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265211222 ap554 https://padlet.com/ap554/ar4iu60pmb0m/wish/265214177

Galapagos fur seal- Arctocephalus galapagoensis

Steller sea lion- Eumetopias jubatus

Northern fur seal- Callorhinus ursinus

Leopard Seal- Hydrurga leptonyx

Guadalupe fur seal- A. townsendi

Southern sea lion- Otaria byronia

Crabeater Seal- Lobodon carcinophaga

Grey Seal- Halichoerus grypus

California seal lion- Zalophus californianus

Hawaiian monk seal- Neomonachus schauinslandi

]]> 2018-06-03 14:35:29 UTC https://padlet.com/ap554/ar4iu60pmb0m/wish/265214177