marine mammals, birds and reptiles to the land and back 350 mya - tetrapods evolve from fish need:...
TRANSCRIPT
To the Land and BackTo the Land and Back
350 MYA - Tetrapods evolve from fish Need:
Lungs Forelimbs Ability to avoid drying out
Some move back to the oceans - new adaptations required
350 MYA - Tetrapods evolve from fish Need:
Lungs Forelimbs Ability to avoid drying out
Some move back to the oceans - new adaptations required
Sea TurtlesSea Turtles
Enclosed by carapace Cannot retract head Flippers Return to land to
reproduce after long migrations
All threatened to endangered
Enclosed by carapace Cannot retract head Flippers Return to land to
reproduce after long migrations
All threatened to endangered
Sea SnakesSea Snakes Tropical Indian and
Pacific Laterally compressed Ovoviparous Small mouth but
highly venomous
Tropical Indian and Pacific
Laterally compressed Ovoviparous Small mouth but
highly venomous
Marine IguanasMarine Iguanas
Galapagos Live in large
colonies Herbivores Salt glands in
nose
Galapagos Live in large
colonies Herbivores Salt glands in
nose
QuickTime™ and a decompressor
are needed to see this picture.
Saltwater CrocodileSaltwater Crocodile
Very large (usually max of 20 ft.)
Usually found in coastal areas
Highly aggressive
Very large (usually max of 20 ft.)
Usually found in coastal areas
Highly aggressive
SeabirdsSeabirds Homeothermic /
Endothermic Oil glands Feathers Light, hollow
bones Hard egg shell
Homeothermic / Endothermic
Oil glands Feathers Light, hollow
bones Hard egg shell
But can they do this??!!
PenguinsPenguins
Flightless Denser bones (reduces
buoyancy) Layer of fat plus
feathers for warmth Southern hemisphere Mating practices
Flightless Denser bones (reduces
buoyancy) Layer of fat plus
feathers for warmth Southern hemisphere Mating practices
TubenosesTubenoses
Heavy curved beak Mostly open sea
predators Elaborate courtship
followed by lifelong pairing
Albatrosses, shearwaters, petrels
Heavy curved beak Mostly open sea
predators Elaborate courtship
followed by lifelong pairing
Albatrosses, shearwaters, petrels
Pelicans and Relatives
Pelicans and Relatives
Webbing between toes
Fish eaters
Webbing between toes
Fish eaters
AUKS!!AUKS!!
Common name for the Alcids May fill penguin niche in Northern
Hemisphere Puffins, razorbills, guillemots, dovekies
(little auks) Great auk extinct in 1844
Common name for the Alcids May fill penguin niche in Northern
Hemisphere Puffins, razorbills, guillemots, dovekies
(little auks) Great auk extinct in 1844
ShorebirdsShorebirds
Herons, egrets, plovers, etc.
Found on coastlines usually for feeding
Often common in freshwater
Herons, egrets, plovers, etc.
Found on coastlines usually for feeding
Often common in freshwater
QuickTime™ and aSorenson Video decompressorare needed to see this picture.
Marine MammalsMarine Mammals
Endothermic/Homeothermic Hair and mammary glands Viviparous and placental Large, complex brain
Endothermic/Homeothermic Hair and mammary glands Viviparous and placental Large, complex brain
PinnipedsPinnipeds
Relatives of Carnivora Blubber and fur Seals, sea lions and walruses
Relatives of Carnivora Blubber and fur Seals, sea lions and walruses
Carnivora - Polar Bears
Carnivora - Polar Bears
Arctic top predators Swim well but hunt on
ice (seals, belugas, etc.) Parental care
Arctic top predators Swim well but hunt on
ice (seals, belugas, etc.) Parental care
Carnivora - Sea OttersCarnivora - Sea Otters
Smallest marine mammal
Lacks blubber but dense fur
Eat a LOT! (Mostly inverts)
Parental care Still threatened
Smallest marine mammal
Lacks blubber but dense fur
Eat a LOT! (Mostly inverts)
Parental care Still threatened
QuickTime™ and aSorenson Video 3 decompressorare needed to see this picture.
SireniansSirenians
Manatees and dugongs No rear limbs Paddle shaped tail Thick blubber layer but
almost no hair Four remaining species
(all endangered)
Manatees and dugongs No rear limbs Paddle shaped tail Thick blubber layer but
almost no hair Four remaining species
(all endangered)
CetaceansCetaceans
Largest group of marine mammals Entirely aquatic Convergent evolution
Largest group of marine mammals Entirely aquatic Convergent evolution
RespirationRespiration
Nasal drift Rapid air movement 90% oxygen delivery from lungs! Blood adaptations:
Greater blood volume More erythrocytes with more hemoglobin Extra myoglobin in muscles
Lowered HR and restricted blood flow Lung collapse?? Exhalation before diving??
Why??
Nasal drift Rapid air movement 90% oxygen delivery from lungs! Blood adaptations:
Greater blood volume More erythrocytes with more hemoglobin Extra myoglobin in muscles
Lowered HR and restricted blood flow Lung collapse?? Exhalation before diving??
Why??
EcholocationEcholocation Toothed whales, some pinnipeds and baleen
whales
Toothed whales, some pinnipeds and baleen whales
It’s cold down there!!It’s cold down there!!
Blubber - useful as insulation and as energy reserve
Fur in pinnipeds and carnivora Blood vessels in whale tongues transfer
heat back to core
Blubber - useful as insulation and as energy reserve
Fur in pinnipeds and carnivora Blood vessels in whale tongues transfer
heat back to core
Reproduction - Cetaceans
Reproduction - Cetaceans
Copulation in water Competition and cooperation Sex play 11-12 month gestation Birth Maternal care
Copulation in water Competition and cooperation Sex play 11-12 month gestation Birth Maternal care
Reproduction - PinnipedsReproduction - Pinnipeds
Monogamy vs. polygamy Harems and bachelor groups
Maternal care Variation in nursing period Females return
Delayed implantation allows birth to coincide with return to shore
Monogamy vs. polygamy Harems and bachelor groups
Maternal care Variation in nursing period Females return
Delayed implantation allows birth to coincide with return to shore