amnions

Reptiles, birds, and mammals are amniotes. Amniote embryos develop in a fluid-filled sac. The amniotic sac contains everything an embryo needs to grow. The amniotic egg allowed vertebrates to reproduce on land. some develop inside mother’s body some develop inside a tough, semipermeable shell

Embryo Allantois Holds waste materials as the embryo grows Yolk sac Contains the nutrient supply for the growing embryo Amnion Protects and surrounds the embryo Chorion Allows gas exchange with outside environment

All amniotes have two circuits of blood vessels. –pulmonary circuit moves blood from the heart to the lungs –systemic circuit moves blood from the heart to the rest of the body Amniotes have a three- or four- chambered heart. –reptiles hearts have three chambers –birds and mammals hearts have four chambers THREE-CHAMBERED HEART FOUR-CHAMBERED HEART

Amniotes evolved into three different groups. – synapsids – anapsids – diapsids Holes behind the eyes

Reptile Skulls Anapsid – No opening Synapsid – One opening Diapsid – Two openings Euryapsid – One small opening

Reptiles were the first amniotes.

Reptiles characteristics. 1.ectotherms 2.covered with dry scales 3.amniotic eggs 4.three-chambered heart 5.Cloaca Common opening for Reprod., dig. and excretory 6. claws

scales

Exothermic

Reptiles have two reproductive strategies. –Oviparous reptiles deposit eggs into an external nest. –Viviparous reptiles retain eggs and give birth to live offspring.

Reptile orders Rhynchochephalia – tuataras Squamata – lizards and snakes Chelonia – turtles and tortoises Crocodilia – crocodiles and alligators rhynchochephalia squamata chelonia crocodilia

closely related to lizards. –Diapsids –two holes in skull –primitive characteristics –two species Tuatara Order Rhychocephalia Characteristics 1.No flexible jaw 2. Teeth fused to jaw 3. Heart very primitive Found in Australia and New Zealand Nova Lizard Kings

Order Chelonia Turtles, tortoises, and terrapins are the remaining anapsids. – bony shell encases body – 200 species – No teeth Tortoises hard plated shells legs with claws head retracts terrestrial Gopher tortoise

Giant Tortoise Lifespan 150 Years

turtles – Aquatic – Leather like shells – Flipper like legs – Head does not retract into the shell

Leatherback Sea Turtle Loggerhead sea turtle

Expeditions Sea Turtles List the 5 major sea turtles What % of sea turtles hatch? How is sex determined? How long does it take for the eggs to hatch? What is the major conservation efforts for the sea turtles?

turtles

Turtle Shell Carapace Plastron

carapace plastron V = vertebral scute C = costal scute M= marginal scute G= gular scute P= pectoral scute AB=abdominal scute F = femeral AN=anal scute Shell Dorsal – carapace Ventral – plastron –greatly reduced

Turtle ladies of Charleston List 6 things that impact the turtles How many eggs are laid in each nest How many nest are laid each year What is the only turtle that imprints When do sea turtles reach sexual maturity What turtles never come onto the beach What is a TED and where is it used What is the state reptile

Order Crocodilian montage.gwd50.k12.sc.us/SAFARI/montage/play.php?keyindex=3688&location=loca l& montage.gwd50.k12.sc.us/SAFARI/montage/play.php?keyindex=3688&location=loca l& Ultimate Croc 1.How many eggs are laid and how many hatch? 2.How is sex determined? 3.What is the survivor rate? 4.How do croc’s keep cool? 5.How long do hatchlings stay with mom? 6.How do males attract a mate? diapsids semi-aquatic predators 23 species 4 chambered heart

Alligator Crocodile Caiman Gavial

Alligator Round nose Teeth not exposed when the mouth is closed Found in SC

Crocodile Pointed nose Teeth extend when mouth is closed Not found in SC

Caiman Elevated eyes Gavial

Order Squamata Snakes and lizards

Snakes and lizards are very closely related and share a number of features. –diapsids –shed skin at regular intervals –flexible skull –Jacobson’s organ in tongue Jacobson’s organ

Texas Horned Lizard Wall Lizard Geckos

Gecko

Chameleons Gila Monster Green Iguana montage.gwd50.k12.sc.us/SAFARI/montag e/play.php?frompage=player&digitallibrary keyindex=3546&keyindex=3546&location=l ocal&chapterskeyindex=- 1&keyconceptskeyindex=- 1&sceneclipskeyindex=-1http://ghs- montage.gwd50.k12.sc.us/SAFARI/montag e/play.php?frompage=player&digitallibrary keyindex=3546&keyindex=3546&location=l ocal&chapterskeyindex=- 1&keyconceptskeyindex=- 1&sceneclipskeyindex=-1 Iquanas of the galopogus

Snakes No legs No external ears Jacobson’s organ – Sense smell with aid of tongue Cornea of eye protected with a spectacle – transparent membrane Skull bones loose – Swallow large prey montage.gwd50.k12.sc.us/SAFARI/mo ntage/play.php?keyindex=5398 rattlesnakes

Questions ?

Non-venomous & Venomous Shape of head – NV often slender, – V broad, triangular-shaped Scales underneath tail toward tip – NV divided, – V undivided Pupil – NV round, – V like a cat’s eye, vertical Presence of Pit – NV no pit between eye & nostril – V pit between the eye & nostril

Venom - complex mixture of proteins, enzymes, and various other substances. The proteins are responsible for the toxic and lethal effect of the venom and its function is to immobilize prey, enzymes play an important role in the digestion of prey, and various other substances are responsible for important but non-lethal biological effects

Neurotoxin – affects nervous system, usually fast acting, a quick death most of the time Hemotoxin – affects the red blood cells, slower acting, antivenom available

Snake Facts 39 species of snakes in SC 6 species are poisonous 3 in Greenwood Snakes are beneficial, very few bites About half of SC snakes bear young alive, others lay eggs Poisonous snakes are live bearing Diets include rodents, rabbits, insects, other snakes, crawfish, bird eggs Snake folklore expeditions

Six Poisonous Snakes in SC Timber/Canebrake Rattlesnake – timber in mountains & Piedmont, canebrake in coastal Copperhead Common in SC

Pigmy Rattlesnake – uncommon statewide, except extreme NW Cottonmouth Moccasin abundant light & dark phase

Eastern Diamondback Rattlesnake – rare – color variations Eastern Coral Snake rare

Common Non-poisonous Snakes Rat Snake – black & gray Corn Snake common

Eastern/Black Kingsnake – common Brown Water Snake abundant Common Garter Snake

Worm Snake Scarlet Snake Scarlet King Snake/Eastern Milk Snake

Black racer Redbelly Water Snake Ringneck Snake Northern Water Snake Common in Piedmont & mountains

Banded Water Snake Southern Hognose Snake Eastern Indigo Snake federally threatened

Best Practices for Snake Problems 1.Remove Food Sources 2.Remove Shelter 3.Exclusion

In Case of Snakebite Non-venomous – wash thoroughly Venomous – Try to stay calm! – Keep bitten body part below heart level & remove rings, watches, and tight clothing. – Try to ID snake & get to nearest hospital – American Association of Poison Control Centers ( ) for correct antivenin

bs.org/video/ / Nova video The four winged Dinosaurs

Archaeopteryx 147 MYA Transitional fossil – Characteristics of reptiles – Characteristics of birds