Chapter 34Overview: Half a Billion Years of BackbonesSlide 3Slide 4Slide 5Concept 34.1: Chordates have a notochord and a dorsal, hollow nerve cordLE 34-2Derived Characters of ChordatesLE 34-3NotochordDorsal, Hollow Nerve CordPharyngeal Slits or CleftsMuscular, Post-Anal TailTunicatesLE 34-4aSlide 16LE 34-4cLanceletsLE 34-5Early Chordate EvolutionSlide 21LE 34-6Concept 34.2: Craniates are chordates that have a headDerived Characters of CraniatesLE 34-7aSlide 26LE 34-7cThe Origin of CraniatesLE 34-8aSlide 30LE 34-8bHagfishesLE 34-9Concept 34.3: Vertebrates are craniates that have a backboneDerived Characters of VertebratesLampreysSlide 37Fossils of Early VertebratesLE 34-11Slide 40Slide 41Origins of Bone and TeethConcept 34.4: Gnathostomes are vertebrates that have jawsDerived Characters of GnathostomesLE 34-13Slide 46Fossil GnathostomesLE 34-14aSlide 49LE 34-14bChondrichthyans (Sharks, Rays, and Their Relatives)Slide 52LE 34-15aLE 34-15bSlide 55LE 34-15cSlide 57Ray-Finned Fishes and Lobe-FinsSlide 59Slide 60LE 34-16Ray-Finned FishesLE 34-17aLE 34-17bLE 34-17cLE 34-17dSlide 67Lobe-FinsSlide 69Concept 34.5: Tetrapods are gnathostomes that have limbs and feetDerived Characters of TetrapodsThe Origin of TetrapodsLE 34-19Slide 74LE 34-20AmphibiansSlide 77LE 34-21aSlide 79LE 34-21bSlide 81LE 34-21cSlide 83LE 34-22aLE 34-22bLE 34-22cConcept 34.6: Amniotes are tetrapods that have a terrestrially adapted eggLE 34-23Derived Characters of AmniotesLE 34-24Slide 91Early AmniotesReptilesSlide 94Slide 95The Origin and Evolutionary Radiation of ReptilesSlide 97Slide 98Slide 99LepidosaursLE 34-27aSlide 102LE 34-27bSlide 104LE 34-27cTurtlesLE 34-27dAlligators and CrocodilesLE 34-27eBirdsDerived Characters of BirdsSlide 112LE 34-28The Origin of BirdsLE 34-29Living BirdsLE 34-30aSlide 118LE 34-30bLE 34-30cLE 34-30dSlide 122LE 34-31Concept 34.7: Mammals are amniotes that have hair and produce milkDerived Characters of MammalsEarly Evolution of MammalsLE 34-32Slide 128MonotremesLE 34-33MarsupialsLE 34-34aSlide 133LE 34-34bSlide 135LE 34-35Eutherians (Placental Mammals)LE 34-36LE 34-36aLE 34-36bLE 34-36cLE 34-36dLE 34-36eLE 34-36fLE 34-36gLE 34-36hLE 34-36iLE 34-36jLE 34-36kLE 34-36lSlide 151PrimatesDerived Characters of PrimatesLiving PrimatesSlide 155Slide 156LE 34-38Slide 158LE 34-39Slide 160LE 34-40aLE 34-40bLE 34-40cLE 34-40dLE 34-40eConcept 34.8: Humans are bipedal hominoids with a large brainDerived Characters of HominidsThe Earliest HumansLE 34-41Slide 170Slide 171AustralopithsLE 34-42aLE 34-42bLE 34-42cBipedalismTool UseEarly HomoSlide 179Slide 180Slide 181NeanderthalsHomo sapiensSlide 184Slide 185Slide 186Slide 187Copyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsPowerPoint Lectures for Biology, Seventh EditionNeil Campbell and Jane ReeceLectures by Chris RomeroChapter 34Chapter 34VertebratesCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsOverview: Half a Billion Years of Backbones•By the end of the Cambrian period, about 540 million years ago, an astonishing variety of animals inhabited Earth’s oceans•One type of animal gave rise to vertebrates, one of the most successful groups of animalsCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings•The animals called vertebrates get their name from vertebrae, the series of bones that make up the backboneCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsCopyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings•There are about 52,000 species of vertebrates, including the largest organisms ever to live on the EarthCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsConcept 34.1: Chordates have a notochord and a dorsal, hollow nerve cord•Vertebrates are a subphylum of phylum Chordata•Chordates are bilaterian animals that belong to the clade of animals known as Deuterostomia•Two groups of invertebrate deuterostomes, the urochordates and cephalochordates, are more closely related to vertebrates than to invertebratesLE 34-2LE 34-2ChordatesEchinodermata(sister group to chordates)CraniatesVertebratesGnathostomesOsteichthyansLobe-finsTetrapodsAmniotesMilkLegsAmniotic eggLobed finsLungs or lung derivativesJaws, mineralized skeletonVertebral columnHeadBrainNotochordAncestral deuterostomeCephalochordata(lancelets)Myxini(hagfishes)Cephalaspidomorphi(lampreys)Chondrichthyes(sharks, rays, chimaeras)Actinopterygii(ray-finned fishes)Actinistia(coelacanthus)Dipnoi(lungfishes)Urochordata(tunicates)Amphibia(frogs, salamanders)Reptilia(turtles, snakes,crocodiles, birds)Mammalia(mammals)Copyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsDerived Characters of Chordates•All chordates share a set of derived characters•Some species have some of these traits only during embryonic development•Four key characters of chordates:–Notochord–Dorsal, hollow nerve cord–Pharyngeal slits or clefts–Muscular, post-anal tailLE 34-3LE 34-3Pharyngealslits or cleftsMouthBrainDorsal,hollownerve cordNotochordMusclesegmentsMuscular,post-anal tailAnusCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsNotochord•The notochord is a longitudinal, flexible rod between the digestive tube and nerve cord•It provides skeletal support throughout most of the length of a chordate•In most vertebrates, a more complex, jointed skeleton develops, and the adult retains only remnants of the embryonic notochordCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsDorsal, Hollow Nerve Cord•The nerve cord of a chordate embryo develops from a plate of ectoderm that rolls into a tube dorsal to the notochord•The nerve cord develops into the central nervous system: the brain and the spinal cordCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsPharyngeal Slits or Clefts•In most chordates, grooves in the pharynx called pharyngeal clefts develop into slits that open to the outside of the body•Functions of pharyngeal slits:–Suspension-feeding structures in many invertebrate chordates–Gas exchange in aquatic vertebrates–Develop into parts of the ear, head, and neck in terrestrial vertebratesCopyright © 2005 Pearson Education, Inc. publishing as Benjamin CummingsMuscular, Post-Anal Tail•Chordates have a tail posterior to the anus•In many species, the tail is lost during embryonic development•The tail contains skeletal elements and muscles•It provides