1. Vertebrate Animals (The Animals You’re Most Familiar With)

2. Phylum: Chordata Vertebrate Animals

3. Notochord –Supportive Longitudinal Rod (becomes a backbone in most Vertebrates) Dorsal Hollow Nerve Cord –Creasted from ectoderm infolding Pharyngeal Gill Slits –Pouches or grooves along the pharynx Post-Anal Tail Phylum: Chordata

4. Chordata Subphylum: Urochordata (Tunicates) –Simplest & Most Ancient Chordates –Adult is a Sessile filter-feeder METAMORPHOSIS –Larva is a free-swimming “tadpole” ADULT LARVA

5. Subphylum Urochordata (Tunicates) Chordata

6. Subphylum Cephalochordata (Lancelets) –Both Larva & Adult are “tadpole-like” –Neotony – retention of larval characteristics in the adult – “juvenile” characteristics are carried into adulthood. (Metamorphosis becomes less pronounced) Chordata

7. Subphylum Vertebrata (Vertebrates) Chordata Notochord is composed of segments (sometimes bony “vertebrae”), often enclosing the dorsal hollow nerve cord. “Craniates” = advanced cephalization (formation of a head region – a cranium).

8. Vertebrate CLASSES: –Cephalaspidomorphi –Placodermi –Chondrichthyes –Actinopterygii –Sarcopterygii –Dipnoi –Amphibia –Reptilia Aves –Mammalia Chordata (Neotony)

9. CLASS Cephalaspidomorphi (Lampreys) –Hollow cartilage endoskeleton (with segmented projections) surrounding a persistent notochord. –Jawless (Agnathostomes) –Mostly parasitic Chordata

10. CLASS Placodermi (Placoderms) –1 st Jawed vertebrates (Gnathostomes) –Extinct –Armored plates. –Likely a cartilage endoskeleton Chordata

11. CLASS Chondrichthyes (Sharks, Rays) –Cartilaginous Fish – Cartilage endoskeleton. –Well-developed jaws. –Continual swimmers (density > water) –Placoid (tooth-like) scales (actual teeth too) –Oviparous, Ovoviviparous, or Viviparous Chordata

12. CLASS Actinopterygii (Ray-finned Fish) –(Osteichthyes) - bony fish (calcium phosphate- enriched endoskeleton = ossified endoskeleton) –Highly maneuverable (ray-fins) –Swim Bladder (buoyancy control) –Respiratory gills supported by a bony flap. Chordata

13. CLASS Sarcopterygii (Lobe-finned fish) –Large muscular pegs within pectoral & pelvic fins (pulled fish through mud flats). CLASS Dipnoi (Lung fish) –Gulp air into rudimentary lung-like sacs. Chordata Coelacanth (Class Actinistia) Australian Lungfish

14. Chordata Origin of Tetrapods -- 4 limbed organisms Bones & muscles modified for land motility.

15. CLASS Amphibia (Salamanders, frogs) –Metamorphosis (“two lives”). Aquatic herbivorous larva (tadpole) with gills. Semi-aquatic or aquatic carnivorous adult, sometimes with lungs. –Skin often functions in gas exchange. –Water required to complete the life cycle. Chordata

16. Origin of Amniotes – an amniotic egg (surrounded by layers of tissue) –allows for exclusive occupation of land.

17. CLASS Reptilia (dinosaurs, lizards, snakes, turtles, birds) –Skin with Keratinized scales. –Lungs. –Most are Ectothermic (cold-blooded). Chordata

18. …BIRDS –Surviving Dinosaurs –Endothermic –Feathers are modified scales –Bones hollow

19. Chordata CLASS Mammalia (Monotremes, Marsupials, Placentals) –Mammary Glands – rich nutritive milk for offspring (increased parental care). –Hair (modified skin). –Endothermic. –Diaphragm. –Specialized dentition.

20. Mammals Monotremes (Spiny Echidna, Platypus) –Oviparous (egg-laying) –Australia

21. Mammals Marsupials (Kangaroo, Possum, Wombat) –Placentals –Viviparous (young born live, but immature)

22. Mammals Eutherians (Rodents, Elephants, Bears, Cats, Dogs, Primates, Whales, Bats, etc.) – Placentals –Viviparous (young born live & relatively mature)