The Amazing Reptiles of the World

1. The Amazing Reptiles of the World By: Cameron Bernard, Ryan Kiewit, & Cameron Flores

2. Reptile Classification Class: Reptilia(Known for dry skin, epidermal scales, and respiration through the use of lungs) Order Testudines(Lack of teeth in adult form, instead they have modified beaks) Order Crocodylia(Elongated, full with muscles) Order Sphenodontida (Primitive lizards with well developed partial eyes) Order Squamata(Recognized by skull and jaw structures, most successful reptiles)

3. Order Testudines • Examples: Turtles & Tortoises • There are approximately 300 different species • The bony shell, limbs articulating inward towards the ribs, and the keratinized beak characterize turtles • The ventral portion of the shell is referred to as the plastron • The dorsal portion of the shell is referred to as the carapace which connects to the vertibrae, expanded ribs, and bones in the dermis of the skin

4. Order Crocodylia • Examples: Crocodiles, Alligators, Gavials, ad Caimans • Approximately 21 different species • They use their elongated snaps to capture its prey by utilizing swift sideways sweeps of the head • Nostrils at the end of the snout enables for the animal to breathe while submerged • Their muscularly elongated tail allows for swimming, offensive and defensive maneuvers, and attacking prey • Teeth are only necessary for seizing prey because they swallow their meals whole! • Crocodilians eat rocks and other sharp objects to aid in the food digestion process

5. Order Sphenodontida • Examples: Tuataras or lizard like reptiles • Nearly 200 million years ago in the Mesozoic era, tuataras became nearly extinct • Two rows of teeth on the upper jaw enable easy distinguishing among other reptiles • An additional row of teeth on the bottom jaw allows for easy chewing of animals such as birds • Tuataras are now only located in New Zealand and are protected by New Zealand law enforcement of preserved islands

6. Order Squamata • Examples: Snakes, Geckos, Iguanas, Chameleons, and Anolis • The order contains three suborders; Lizards, Snakes, and Worm Lizards • Lizards generally live on the substrates of rocks and retreat under rocks or logs if necessary • Lizards very in length from a few centimeters to 3 m

7. General Reptile Charactoristics • Unlike the skin of amphibians, reptiles skin has no respiratory function • The skin is dry and thick and some scales are modified for various functions • All reptiles shed • Blood flow does not extend to the epidermis which allows for easy shedding of skin • Reptile skulls have secondary palates which separates the nasal passages from the oral cavity • Reptiles exhibit great flexibility

8. Nutrition and Digestion • Most reptiles are carnivorous, though turtles may be associated as herbivores, or omnivores as well • Snakes have adaptations in their skill necessary for feeding (The skull and jaw detach to allow digestion of food much larder than the snakes head) • Some lizards, anurans, and tuatara possess sticky tongues • Vipers utilize hollow teeth to inject their venom into their prey

9. Circulation • Circulation in reptiles is a lot like that of the amphibian circulatory system • Reptiles have two atria • The ventral aorta and the conusarteriosus divide during development in crocodiles • The pulmonary artery leaves the ventral side of the ventricle and takes blood to the lungs • Reptiles can go “apnea” which is a period of not breathing, turtles use this to conserve energy and permit more efficient oxygen usage

10. Gas Exchange • Reptiles utilize the ability to exchange gas across internal respiratory surfaces in order to avoid losing large amounts of water • Reptiles have a larynx but generally speaking vocal cords are absent • Lungs are sponge like interconnected chambers lines in cartilage • In many reptiles, a negative-pressure mechanist ventilates the lungs • Reptiles can regulate their body temperatures

11. Nervous System & Sensory Functions • The brain of a reptile is similar to that of other vertebrates in that the cerebral hemisphere is larger than that of amphibians • Reptiles possess binocular vision • Many reptiles have upper and lower eyelids that protect the surface of the eye • Some reptiles even posses a median eye (parietal eye) which are used to better differentiate light and dark orientations of the sun

12. Excretion and Osmoregulation • Kidneys are used in order to filter blood using nephrons • Most reptiles excrete uric acid a nontoxic soluble precipitate • Many reptiles possess water and salt glands that allow them to remove excess waste more easily • The bladder or the cloacal wall can reabsorb water and re use it in order to conserve in extreme climates

13. Reproduction • Some reptiles utilize internal fertilization by the means of using amniotic eggs (allows for eggs to be laid outside of water unlike that of amphibians) • In reproduction, males seek out females actively • Many reptiles display head-bobbing to portray their courtship towards the opposite sex • Reptiles produce pheromones to assess the reproductive potential of a mate • After eggs are laid, they are abandoned on the ground, under rocks, in debris, or in sand

14. Reptilian History • The archosaur depicts lineage of the reptilian species • Reptiles date back to 280 million years ago • Dinosaurs became the ancestors to reptiles • The pterosaurs were part bird, part reptile, and possessed to ability to fly • Many reptiles developed mammal-like characteristics in which were adapted in the Triassic and Carboniferous periods

15. !!Important Vocab!! • Amniotic Egg-The egg of reptiles, birds, and mammals, that allowed vertebrates to invade terrestrial habitats • Autonomy- Self amputation of an appendage for means of survival • Carapace-Dorsal shell of a turtle • Jacobson’s Vomeronasal Organ- Organ used to sample airborne chemicals • Keratin- a tough water-resistant protein found in epidermis of reptiles • Median Eye- A photoreceptor located middorsally on the head of reptiles • Pit Organ- • Plasteron- • Secondary Plate-