2 Vertebrates350 m.y.a. vertebrates invaded landDecendents of bony fishLand vertebrates had to adapt to harsher conditions on shoreTetrapods had to develop lungs that allowed for absorption of oxygen directly from air.Tetrapods had to evolve in ways to keep from drying out.
3 Amphibians, early tetrapods, have eggs that are vulnerable Amphibians, early tetrapods, have eggs that are vulnerable. They need to stay moist and lay them in water.Reptiles on the other hand solved the problem of waterloss, resulting in the evolution of birds and mammals.One they were equipped with adaptations for land they reentered the ocean.
5 ClassificationMarine Reptiles7000 speciesDry skin with scalesEggs leathery shellPoilkilotherms (body temp varies w/environment) and ectotherms (lose metabolic heat to environment)
6 Sea TurtlesShell, carapace, is fused with their backbone.Cannot retract their heads into the shellLegs are modified into flippers for swimmingWarmer waters
7 Feed on seagrass, seaweed, sponges, sea squirts, barnacles, jellyfish Must return to land to reproduceMigrate to original beach, possible use of magnetic fieldsReturn every 2-4 years, copulate offshore, females come on shore at night, dig a hole lay between 100 – 160 eggs, hatch approx. 60 days
8 7 (8) species of Sea Turtles (all classified as threatened); Green (Chelonia mydas)Hawksbill (Eretmochelys imbricata)Leatherback (Dermochelys coriacea) D.o.d,largest turtleKemp’s Ridley (Lepidochelys kempii)Loggerhead (Caretta caretta)Flatback (Natator depressa)Black (Chelonia agassizii)Olive Ridley (Lepidochetys olivacea)
9 Green Sea TurtleHawksbill Sea TurtleFlatback Sea TurtleBlack Sea Turtle
11 Sea Snakes Approx. 55 species found in tropical waters Laterally flattened and tail paddle-shaped for swimming, 3-4ft longMate in the ocean, ovoviviparousClosely related to cobras, rarely aggressive
12 Marine Iguana (Amblyrhynchus cristatus) Galapagos IslandsEats seaweed and can dive 33ft to grazeSaltwater Crocodiles (Crocodylus porosus)Mangroove swamps and estuaries20-33ft long, very aggressive
13 SeabirdsEndothermicWaterproof feathersHollow bonesHard-shelled eggSpend significant amount of time in marine environment and eat marine organisms
14 PenguinsFlightless, wings modified into stubby flippersBones are denser to reduce buoyancyLayer of fat and dense waterproof feathersFeed on fish, squid, and krillLay eggs during cold times of year to ensure food availability when egg hatchesEmperor penguin (Aptenodytes forsteri) mate for life
18 Wading, do not have webbed feet Live inland as well as sea ShorebirdsWading, do not have webbed feetLive inland as well as seaPlovers, sandpipers, rails, coots, herons, egrets, and even ducks
19 Marine Mammals200 m.y.aClass MammaliaEndothermsHair, mostly viviparous (embryo receives nutrients and oxygen through the placenta), mammary gland
20 Pinnipeds – Order Pinnipedia Paddle-shaped flippers for swimmingPredators, fish and squidStreamlined bodiesColdwater, thick layer of fat (blubber)Breed on land
21 SealsLargest group, rear flippers that cannot be moved forwardThey move on land with front flippersHarbor SealsElephant SealsSea Lions andFur SealsEared sealsMove rear flippers forwardUse all limbs to walk/run on landGraceful swimmersMales much larger than femalesCalifornia sea lion
23 Walrus (Odobenus rosmarus) Tusks are used for defenseFeeds on invertebrates that it sucks up from the sea bottomDependent on sea iceOdobenus rosmarus
24 Sea Otter and Polar Bear Order CarnivoraSea Otter (Enhydra lutris)Smallest marine mammal averages between 60 – 80 poundsLacks layer of blubber instead uses air trapped in its dense furBreed and give birth in water, eats up to 30% of its body weight/day (invertebrates and fish)Lives in kelp beds
26 Polar Bear (Ursus maritimus) Semi aquatic animals that live in the Arctic and feeds primarily on sealsDepends on sea ice for survival
27 Manatees and Dugong (sea cows) Order Sirenia, relatives of elephantsPair of front flippers, no rear limbsPaddle – shaped horizontal tailBlubber, live in shallow coastal watersStrict vegetarians, large in size Dugongs (10ft) and Manatees (15ft)Manatee (Trichechus)
29 Whales, Dolphins, and Porpoises Order CetaceaBodies are streamlined, breath air, warm-blooded, have hair, and produce milk for their youngFront flippers, no rear limbs (embryonic stage only)Many have dorsal fin, muscular tail fin-like (fluke)
30 Blubber, provides insulation and buoyancy Single or double opening on the top of their head – blowhole90 species, all marine except 5 freshwater dolphin speciesDivided into two groups; toothless and toothed
32 Baleen (toothless) whales, Mysticeti Rows baleen hang from upper jaws made up of keratinLargest whales, 13 speciesBlowhole has two openingsBlue Whale (Balaenoptera musculus)Largest, males up to 80ft and females up to 110ftWeigh up to 90 – 140 tonsFeed by gulping up schools of fish and swarms of krill
37 Dolphins tend to be classified by their distinctive beaks Porpoises have more blunt shorter “noses”.Bottlenose
38 WhalingEarly as 6000 B.C.Blubber used to make soap and lamp oilBaleen used for corsetsMeat
39 1800sharpoons and steamships made whaling easierPopulation declinewhales have long life spans mammalsslow reproductive rateslow swimmersFactory shipsReached it peak in 1930sRight whales
40 Marine Mammal Protection Act of 1972, 1946, International Whaling Commission (IWC) in attempt to regulate whale huntingIWC collected data and set annual quotasMarine Mammal Protection Act of 1972,US Congress banned the hunting of all marine mammals in the US waters and importation of marine mammal products (except in traditional fisheries of AK natives)
47 Diving Adaptations efficient exchange of air on the surface storage of more oxygen in the blood and muscles as result of high concentration of hemoglobinreduction of the blood supply to the extremitiescollapsible lungs to help prevent the bends.slow their heart rate down conserving oxygentolerance to lactic acid in their muscles
52 Reproduction Delayed implantation (Pinnipeds) Little is known about cetacean reproduction.Gestation lasts for 11 to 12 months in most cetaceans.Calves are born tail firstThey can live more than 40yrs.
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