1. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Vertebrates Chapter 48 Copyright © McGraw-Hill Companies Permission required for reproduction or display

2. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies The Chordates Distinguished by four principle features:  Notochord  Dorsal Nerve Cord  Pharyngeal Slits  Postnatal Tail Muscles arranged in segmented blocks. Most have internal skeleton.

3. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Which is not a characteristic of all Chordates? A) Gill slits B) Notochord C) Hollow dorsal nerve cord D) backbone

4. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies The Nonvertebrate Chordates Tunicates  Exhibit neither a major body cavity nor visible segmentation. - Tadpole larva clearly exhibit all basic characteristics of a chordate. - Adults exist as a sessile, filter-feeders.

5. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies The Nonvertebrate Chordates Lancelets  Scale-less, fishlike marine chordates. - Notochord runs entire length of dorsal nerve cord. - Feed on microscopic plankton using cilia- generated current.

6. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Characteristics of Vertebrates Vertebral Column-develops from notochord Distinct Head Neural Crest Internal Organs Endoskeleton

7. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies What is the difference between the vertebrates and the other chordates? A) The notochord becomes the spinal cord. B) The notochord becomes the backbone. C) The gill slits become the lungs. D) The hollow dorsal nerve cord becomes the backbone.

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9. Fishes Over half of all vertebrates are fishes. Characteristics  Gills  Vertebral Column  Single-Loop Blood Circulation  Nutritional Deficiencies First Fishes  Members of five Ostracoderm orders. - Jawless bottom-dwellers.  Jaws developed about 410 mya. Rise of Active Swimmers  Sharks and bony fishes replaced primitive fishes due to a superior swimming design. - Caudal (tail) Fin - Dorsal (stabilizing) Fins - Pectoral (shoulder - elevator) Fins - Pelvic (Hip- elevator) Fins

10. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies History of the Fishes Sharks were among first vertebrates to develop teeth.  Sit on top of jaws.  Programmed tooth loss. - Teeth are always new and sharp. Extremely advanced reproduction.  Shark eggs fertilized internally.

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12. History of the Fishes Bony Fishes Dominate the Water  Bony fish evolved at same time as sharks, but adopted a heavy internal skeleton made of bone. - Strong base for muscles.  Evolved in fresh water.  Highly mobile fins, thin scales, and completely symmetrical tails. Important Adaptations of Bony Fishes  Swim Bladder - Regulates buoyancy.  Lateral Line System - Assesses rate of movement through water as pressure waves against the lateral line.  Gill Cover (Operculum) - Flexing the operculum permits bony fish to pump water over their gills.

13. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies History of the Fishes Path to Land  Lobe-finned fishes evolved 390 mya. - Have paired fins that consist of a long fleshy muscular lobe supported by a central core of bones that form fully articulated joints.  Amphibians almost certainly evolved from lobe-finned fishes.

14. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Amphibians First vertebrates to walk on land. Characteristics  Legs  Cutaneous Respiration  Lungs  Pulmonary Veins  Partially Divided Heart Adaptations for the Invasion of land  Legs to support body’s weight.  Lung to extract oxygen from the air.  Redesigned heart to drive new respiratory system.  Reproduction in water to prevent egg desiccation.  System to prevent body desiccation.

15. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies History of the Amphibians Rise and Fall of Amphibians  Became common during Carboniferous Period 360- 280 mya.  Began to leave marshes for dry uplands during early Permian Period. - Large size and complete body covering indicate skin was not used as respiratory system. By the end of Permian, therapsid (reptile) ousted amphibians from their niche on land.  By the end of the Triassic, there were only 15 families of amphibians left. - Almost all were aquatic. - Only two groups are known from Jurrassic Period (213-144 mya). - Anuran - Frogs and Toads - Urodelas - Salamanders and Newts

16. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Amphibians Today  Anura - Amphibians without tails.  Most live in or near water, and return to water to reproduce. - Eggs fertilized externally and hatch into tadpoles.  Metamorphosis  Urodela (Caudata) - Salamanders - Have elongated bodies, long tails, and sooth, moist skin.  Fertilization is usually external. Copyright © McGraw-Hill Companies Permission required for reproduction or display

17. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Amphibians Today  Apoda (Gymnophiona) - Caecilians - High specialized group of tropical burrowing amphibians.  Legless, but have jaws and teeth.  Internal fertilization Copyright © McGraw-Hill Companies Permission required for reproduction or display

18. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Reptiles Characteristics  Amniotic Egg - Chorion - Outermost membrane - Amnion - Encases embryo - Yolk Sac - Surrounds Yolk (Food) - Allantois - Surrounds waste cavity.  Dry Skin  Thoracic Breathing

19. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Rise and Fall of Dominant Reptiles Pelycosaurs: A Better Predator  First land vertebrates to kill organisms their own size. Therapsids: Speeding Up Metabolism  Extremely High Food Consumption. - Endotherms ?

20. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Rise and Fall of Dominant Reptiles Thecodonts: Wasting Less Energy  Warmer climates - ectothermic  First bipedal land vertebrates. Dinosaurs: Learning to run  Body located directly over legs. - Increased speed and agility.

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22. Rise and Fall of Dominant Reptiles Other Important Characteristics  Internal Fertilization  Improved Circulatory System  Ectothermic - Heat obtained from external sources. - Endothermic - Generate own heat.  Homeothermic - Constant body temperature.  Poikilothermic - Body temperature fluctuates with ambient temperature.

23. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Rise and Fall of Dominant Reptiles Order Chelonia: Turtles and Tortoises  Differ from other reptiles because their bodies are encased within a protective shell. - Anapsid - Lack temporal opening in the skull, characteristic of other living reptiles. Copyright © McGraw-Hill Companies Permission required for reproduction or display

24. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Rise and Fall of Dominant Reptiles Order Rhynchocephalia: Tuatara  Lizard-like animals about a half-meter long.  Contain parietal eye.  Only found on island off New Zealand coast. Order Squamata: Lizards and Snakes  Three suborders - Sauria - Lizards - Amphisbaenia - Worm Lizards - Serpentes - Snakes  Paired copulatory organ in males.  Lower jaw not joined directly to skull.

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26. Rise and Fall of Dominant Reptiles Order Crocodilia: Crocodiles and Alligators  Remained relatively unchanged. - Only two species of alligators.  Southern US and China  Resemble birds more than other living reptiles (Care for young and four- chambered heart). Copyright © McGraw-Hill Companies Permission required for reproduction or display

27. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Birds Success of birds lies in the feather. Key Characteristics  Feathers - Modified reptilian scales.  Flight Skeleton - Thin, hollow bones. Descended From Dinosaurs  Archaeopteryx  Aves listed as separate class because of the key evolutionary novelties of feathers, light bones, and super-efficient lungs.

28. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies History of the Birds Birds Today  Adaptations for flight energy demands. - Efficient Respiration - Efficient Circulation - Endothermy

29. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Mammals Key Mammalian Characteristics  Hair - Heat Loss - Camouflage - Sensory Structures - Defense Weapon  Mammary Glands Origin of Mammals  First mammals arose about 220 mya.  Tiny shrew-like creatures with large eye sockets - Nocturnal ? Early Divergence  Subclass Prototheria - Duckbill Platypus  Subclass Theria - Marsupials and Placental Mammals Copyright © McGraw-Hill Companies Permission required for reproduction or display

30. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies History of the Mammals Characteristics of Modern Mammals  Endothermy  Placenta  Heterodont Dentition

31. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies History of the Mammals Digesting Plants  Cellulose is a major source of food for herbivores. - Mammals do not have necessary digestive enzymes to break apart cellulose.  Some have evolved four-chambered stomachs.  Some contain mutualistic bacteria in a caecum. Hooves and Horns  Hooves are specialized pads of keratin.  Horns are composed of a core of bone surrounded by a keratin sheath.  Flying Mammals - Bats have a wing of leathery membrane of skin stretched over the bones of four fingers.  Second largest order of mammals.  Echolocation

32. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies History of the Mammals Orders of Mammals  Monotremes: Egg-Laying Mammals - Lay shelled eggs.  Marsupials: Pouched Mammals - Finish development in external pouch.  Placentals - Placenta nourishes embryo throughout entire development.

33. Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Copyright © McGraw-Hill Companies Permission required for reproduction or display