MARINE VERTEBRATES REPTILES AND BIRDS

Transition to Land Acanthostega

Transition to Land must withstand the effects of gravity Descended from bony fishes and from terrestrial reptile groups Four problems these original land verts faced must withstand the effects of gravity must be able to breathe air must minimize water loss (dessication) must adjust senses so they are suited for air instead of water Gravity Changes in skeleton to allow for support, protection of internal organs, shock absorption and distribution of weight Air and breathing Primitive lobe finned fish already had a type of lung. Was adapted to both intake O and remove CO2 Desiccation Dry scaly watertight skin, amniotic egg, Senses Modifications of the eye and ear. Loss of the lateral line

Reptiles- Class Reptilia Warm, temperate climate Ectothermic – produce little metabolic heat Regulate body temperature with behavior or changing habitat Amniotic egg – large yolk for nutrition, leathery shell Scales made of keratin Most with 3-chambered heart Lungs for breathing Can increase and reduce amount of air in lungs to allow diving and regulating buoyancy

Features in Marine Reptiles Biggest anatomical hurdle is keeping internal salt concentrations low and not losing water Salt glands- remove salt from their blood Found above eyes Salt excretions help conserve water and wash sand form their eyes Concentrated urine to conserve water Cannot drink sea water

http://www. chameleonforums http://www.chameleonforums.com/nasal-salt-glands-cause-white-crusts-nose-75998/

Orders of marine reptiles

Orders of Marine Reptiles Crocodilia- Only 1 species Opportunistic predators Testudines- turtles 8 species and all are endangered Diet mostly invertebrates and seaweeds Squamata- Sea snakes and iguanas All sea snakes are venomous Only 1 species of iguana and only in the Galapagos

Crocodile Order Crocodilia Found in Australia, Indian ocean, and some Western Pacific Islands American salt-water crocodile Endangered species (only about 100 remain) Predatory Hunts by remaining just below the water’s surface to ambush prey Can be over 30 feet long Resembles alligators Longer and narrower snout

Crocodiles cont… Has a four-chambered heart Builds nest for eggs Female guards her eggs in nest until they hatch and provides limited care after they hatch

Sea Snakes Order Squamata 55 species found only in the Indian and Pacific Ocean Laterally flattened paddle-like tail for propulsion through the water Most are 3-4 feet in length as adults

Sea Snakes cont… Breed at sea Most species are ovoviviparous Powerful and deadly venom but not aggressive Mainly feed on fish http://www.animalplanet.com/tv-shows/wild-kingdom/videos/diving-for-sea-snakes.htm

Sea Turtles All species of sea turtles are threatened or endangered Kemp Ridley Green Sea Turtle Loggerhead Leatherback Distinguished by size and pattern of scales on their carapace

Sea Turtles Upper shell = Carapace Lower shell = Plastron Skeleton is imbedded into the carapace Have powerful jaws but no teeth.

Sea Turtles, Cont… Breed in the sea but lay eggs above high tide line Females lay up to 800 eggs in 7 different clutches every 2-4 years The temperature determines hatch time and gender In 45 to 75 days after laying the hatchlings return to the sea These nesting sites are important for conservation of sea turtles

Sea Turtle cont.. Adaptations Smooth, streamlined body Limbs evolved to flippers Fatty deposit Lightweight bones

Marine Iguana Species of Lizard Swims and feeds in the ocean Lives on the Galápagos Islands Harmless Graceful movements underwater In 2001, thousands died due to an oil spill

Marine Iguana cont… Flattened Tail aids in swimming Blunt noses for grazing on seaweed/algae in the sub-tidal zone Powerful limbs and sharp claws for clinging to rocks Warm themselves in the sun by laying on the heated lava boulders Excrete concentrated salt crystals from a nasal gland by sneezing Breed on land

Birds-Class Aves Homeothermic Endoderm Over 9000 species Feathers – attached to skin Down feathers insulation Contour feathers flying Powder feathers Water-repelling Gland near tail Produces waterproof oil Preening – spread oil through feathers

Marine Birds Sea birds depend on the ocean for survival Webbed feet Paddling and swimming Hollow bones Adaptation for flight Return to land to breed Eggs encased in a hard, calcium rich shell Salt glands Nasal gland that secretes a salty solution from nostrils Gets ride of excess salt/conserve water Concentrated urine

Marine Birds cont… You can tell what a bird eats by looking at its beak or bill Variation in beak size and shape

Types of Seabirds Shore birds Diving Shore birds Diving Pelagic Birds Feeding in shallow water and water’s edge Sandpiper, oystercatcher, egret, duck, gull Diving Shore birds Dive from the sky to catch food Osprey, tern, cormorant, black skimmer Diving Pelagic Birds Fly long distances to find food Albatross, storm petrel, puffins Penguins

Shorebirds Feed in shallow water and along water’s edge Sandpiper Narrow pointed bill for poking in the sand for small invertebrates Oyster Catcher Long, red, knife-like beak to catch and eat various types of mollusks Snowy Egret Long flexible neck Pointed bill Long, stilt-like legs

Shorebirds, cont… Ducks Seagulls Webbed feet Layers of fat Down/waterproof feathers Flat bills Seagulls Most identified with the ocean Prefer isolated nesting places on offshore islands Scavengers

Diving Shore Birds Dive from the sky to catch food. Cormorant Tern Dives from the sky for its food Hooked beak for catching fish Tern Nests on sandy beaches Hovers over the water before it dives Lays its eggs in the sand Brown Pelican Large Found on the Florida, Gulf, and California coasts Large throat pouch used like a net to scoop fish https://www.youtube.com/watch?feature=player_embedded&v=k-JjI4sgWyg

Diving Shore Birds, cont… Black Skimmer Flies low over the water Skims surface with tip of lower jaw Swallows fish while still in flight Osprey “fish hawk” Keen vision Spots prey from high up Talons Grab and hold onto fish Long powerful wings

Diving Pelagic Birds Fly long distances to find food Albatross Found in the South Pacific Largest of all seabirds Wingspan of 3 meters Glides on air currents over the ocean 3-4 years at sea Could circle the whole globe

http://www. britannica http://www.britannica.com/EBchecked/media/161773/Scientists-measuring-the-wingspan-of-an-albatross

Penguins Most aquatic of all marine birds About 15 species Flightless Good swimmers/divers Only found in the southern hemisphere Antarctic/part of Argentina Eat fish, krill, squid, and shellfish http://youtu.be/96yynCGST8U

Penguin Adaptations Small wings that function as flippers Dense bones Weight for deep dives Males and females care for eggs and young Thick layer of fat under skin Densely packed soft down feathers insulation