Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
31-1 Reptiles Slide 1 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles What Is a Reptile? What Is a Reptile? A reptile is a vertebrate that has dry, scaly skin, lungs, and terrestrial eggs with several membranes. These characteristics enable reptiles to live their entire lives out of water. Slide 2 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Evolution of Reptiles Evolution of Reptiles Reptiles were the first vertebrates that were not dependent on water for reproduction. The first reptile fossil dates back to the Carboniferous Period. Slide 3 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Evolution of Reptiles Dinosaurs During the late Triassic and Jurassic periods, a great adaptive radiation of reptiles took place. The Mesozoic Era is often called the Age of Reptiles. Slide 4 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Evolution of Reptiles All of dinosaurs belonged to one of two major groups: • Ornithischia, or “bird-hipped” dinosaurs • Saurischia, or “lizard-hipped” dinosaurs Slide 5 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Form and Function in Reptiles Adaptations that have contributed to the success of reptiles on land are: • well-developed lungs • a double-loop circulatory system • a water-conserving excretory system • strong limbs • internal fertilization • shelled, terrestrial eggs Slide 6 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Form and Function in Reptiles Body Temperature Control Reptiles are ectotherms. Ectotherms are animals that rely on behavior to control body temperature. To warm up, they bask in the sun or stay under water at night. To cool down, they move to the shade or take shelter in underground burrows. Slide 7 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Form and Function in Reptiles Reproduction Most reptiles are oviparous, laying eggs that develop outside the mother’s body. All reptiles reproduce by internal fertilization, in which the male deposits sperm inside the female’s cloaca. Slide 8 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Form and Function in Reptiles The shell and membranes protect the embryo and prevent the egg from drying out. This type of egg, an amniotic egg, is one of the most important adaptations to life on land. An amniotic egg has four membranes—the amnion, the yolk sac, the chorion, and the allantois. Slide 9 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Groups of Reptiles Groups of Reptiles The four surviving groups of reptiles are: • lizards and snakes • crocodilians • turtles and tortoises • tuatara Slide 10 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Groups of Reptiles Lizards Most lizards have four legs and clawed toes. Most lizards have external ears and movable eyelids. Some lizards have evolved into highly specialized forms. Slide 11 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Groups of Reptiles Snakes Snakes have no legs. Snakes have immovable eyelids and no external ear openings. Snakes are efficient predators. Slide 12 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Groups of Reptiles Crocodilians Crocodilians have long, broad snouts and a squat appearance. They prey on animals such as fishes, deer, and eve humans. Includes Crocodiles and Alligators Slide 13 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Groups of Reptiles Turtles and Tortoises Turtles live in water. Tortoises live on land. A terrapin is a turtle that lives in water that is somewhat salty. Slide 14 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Groups of Reptiles Turtles and tortoises have a two-part shell built into the skeleton: • • a dorsal part, or carapace a ventral part, or plastron The head, legs, and tail emerge from holes where the carapace and plastron join. Tortoises and most turtles pull into their shells for protection. Slide 15 of 50 Copyright Pearson Prentice Hall End Show 31-1 Reptiles Groups of Reptiles Tuataras Tuataras are found only on a few islands off New Zealand. They lack external ears and retain primitive scales. They have a “third eye,” which is part of a complex organ located on top of the brain. Slide 16 of 50 Copyright Pearson Prentice Hall End Show