PPT-Origin of Tetrapods, Amphibians and Reptiles

Chapter 34 Never grow a wishbone where your backbone ought to be Clementine Paddleford Origin of Tetrapods First tetrapods diverged 365 million years ago and shallow inland lakes with muddy bottoms likely selected for early . Introductory Video. Objective: Students will identify vertebrates and classify some as birds and fish.. Lesson 2.1 God's Design of Vertebrates. Unique. One of a kind. Verterbrate: An animal with a backbone. Vocabulary. Scaly. : . covered in scales.. Extinct. : . (of a species, family, or other larger group) having no living members.. Flee. : . Run away from a place or situation of danger.. Elongated. : . Phylum: . Chordata. . Subphylum:Vertebrata. Order. Testudines. Rhynchocephailia. Squamata. Crocodilia. Common . example. Turtles and tortoises. Tuataras-found only in New Zealand. Lizards, snakes, and worm lizards. Encloses spinal cord, (dorsal aorta). Site of muscle attachment. Suspends body - . tetrapods. . . Somites. Somites. . – metameric blocks . of . mesoderm that . form early in development. Somites in green. Chapter 34. “Never grow . a wishbone . where your backbone ought to be” . -Clementine . Paddleford. Origin of . Tetrapods. First . tetrapods. diverged 365 million years ago . (________). ________________________and shallow inland lakes with muddy bottoms likely selected for early . History of Reptiles. Reptiles arose from amphibians. Earliest fossils 359 . m.y.a. Small, four – legged vertebrates w/small teeth. Pangaea. Drier climate. Mass extinction during Paleozoic era. Diversified to fill niches left by extinct species. Fully adapted for life on land. All Amniotes – produce Amniotic Eggs. Dry, Scaly Skin. Ectothermic . More Efficient Circulatory and Respiratory Systems. Cloaca . Except for snakes, Reptiles have Paired limbs, most ending in 5 clawed toes . Amphibians are eukaryotic, heterotrophic vertebrates. They have thin, smooth, moist skin. Some of them have fish-like scales and none of them have claws.. They are ectothermic (coldblooded).. They have external gills and lungs.. Adaptations to Meet Challenges of Life on Land. Challenges of Life on Land vs. Water. Adaptation to Meet Challenge . Air much less buoyant than water so must move against gravity. Limbs develop;. skeletal and muscle systems become stronger. Fully adapted for life on land. All Amniotes – produce Amniotic Eggs. Dry, Scaly Skin. Ectothermic . More Efficient Circulatory and Respiratory Systems. Cloaca . Except for snakes, Reptiles have Paired limbs, most ending in 5 clawed toes . Amphibians “Double Life” Adaptations to Meet Challenges of Life on Land Challenges of Life on Land vs. Water Adaptation to Meet Challenge Air much less buoyant than water so must move against gravity Amphibians and Reptiles Class Amphibia Amphibia =Double Life Frogs, toads, salamanders, and caecilians ~6000 species Skin with mucoid secretions, lack epidermal scales, feathers or hair Larvae are usually aquatic and Characteristics of Class Amphibia. Most amphibians. are . tetrapods. , meaning they have . four limbs. , but . some are limbless. .. Amphibians have . smooth, moist skin. .. Amphibians . respire by lungs, skin, and gills;. Ecological Fitness. How well an organism has adaptations well suited to its environment. An ecologically fit organism has a survival advantage . Adaptation. An inherited characteristic that increases an organism’s ability to survive an environmental change.