Vertebrate Animals

1. Vertebrate Animals Pima Medical Institute Veterinary Technician Program VTT 200 General Sciences-Biology

2. Phylum Chordata • Animals with a developed brain and spinal cord, and extremities to aid in the movement to land, but not all have backbone

3. Phylum Chordata: Sub-Phyla • Tunicata:very ancient group of worm like animals with a spinal cord, but no backbone (no vet importance); only found in small area of ocean near Australia • Vertebrata:animals with developed brain, spinal cord AND backbone on inside (endoskeleton); • -All vertebrates have developed head with sensory organs & closed circulatory & respiratory systems • -All vertebrates have specialized connective tissue leading to establishment of cartilage and bone

4. 7 Classes of Phylum Chordata Sub-phylum Vertebrata • Agnothastomata (jawless fishes) • Chondrichthyes (boneless fishes) • Osteichthyes (bony fishes) • Amphibia • Reptilia • Aves • Mammalia

5. Vertebrate Chordates: simplest/most primitive form: FISH Fish are the most primitive of vertebrate chordates (Ichthyology is the study of fish) ALL FISH: • Oviparous: egg layers • Gill breathers • Paired fins • 2-chambered heart— WHY only 2 chambers needed?

6. Class Chondrichthyes • Sharks, skates & rays • Ancient class of marine fishes with predominantly cartilage structure— • Very little change in thousands of years of development—excellent predators

7. Class Osteichthyes • Osteichthyes (bony fishes) • Some are marine, some are fresh water • Most reproduce with external fertilization (which is less efficient because predators can eat the eggs) See “Finding Nemo”

8. VertebrateChordates-Amphibia Class Amphibia (latin for “double life” between fish & higher animals like reptiles) • First creatures to live on land and sea • Larva have gills; adults have lungs • Scaleless skin; moist to touch • First animals with 3-chambered heart, but are Ectothermic (cold-blooded) meaning they gather heat from environment

9. Orders of Amphibians • Old named Orders of Amphibians: • Anura “without tail” (frogs and toads) • Urodela “with tail” Newts are aquatic; Salamanders are terrestrial

10. Vertebrate Chordates-Reptilia Class Reptilia (Herpetology is study of reptiles) All Reptiles: • Oviparous egg-layers with amniotic sac; internal fertilization • Keratinized epidermis in scales • 3 chambered heart and ectothermic • No gills, use lungs and air sacs

11. Orders of Class Reptilia • Order Chelonia(beak like) scales form a shell • turtles are water dwellers; tortoises terrestrial • Order Crocodilia • Alligators exclusive to fresh water with short & blunt snout • Crocodiles are tropical with longer snout & protruding teeth • Order Squamata are the snakes and lizards • Sub-order Sauria are lizards • Sub-order Serpentis are snakes

12. Vertebrate Chordates-Aves Class Aves (birds are more developed than amphibians and reptiles) Ornithology is the study of birds

13. Class Aves– All Birds: • Epithelial tissue expressed as skin & feathers • All species have rear extremities, front extremities modified into wings • No teeth, utilize crop & gizzard to grind food • Bones are all hollow, spongy bone for flight • 4 chambered heart and endothermic (warm-blooded) can regulate temperature from within • Lungs and air sacs in respiratory • Internal fertilization with anatomical device called cloaca which is organ shared between urinary, digestive & reproductive systems • Excellent vision organs, high metabolic rate

14. Class Aves Two Main divisions: Ratites (flightless birds-ostriches, emus) Carinates (with large breastbone and large breast muscle for flying & wing support)

15. Orders of Class Aves • Orders of Carinates: • Psittaciformes: (hookbills) parrots, macaws • Passerformes: (soft billed perching birds) finches,canaries, • Faloniformes: (raptors-carnivorous & can be predatory or scavenger) eagles, hawks • Strigiformes: Owls • Galliformes: (poultry) chickens, turkeys, quail • Anseriformes: Waterfowl • Many other orders including various storks, flamingoes, penguins, etc.

16. Vertebrate Chordates—Mammalia Final & Most Developed Class Mammalia What makes mammals different from other Vertebrate Chordates? (Viviparous “live birth” & mammary glands)

17. Class Mammalia—All Mammals: • Internal Fertilization • Keratinized hair layer • First animals with diaphragm • 4 chambered heart, circulatory system & endothermic • Well developed brain and nervous system • Some senses better than others depends on species • Has gills as embryo developing into respiratory system with lungs after birth

18. Two Main Divisions of MammalsPrototheria and Eutheria Theria refers to placenta in birth What does Pro- Mean? Prototheria(no placenta in birth) Monotremes are Platypus that actually lays eggs— transition animal from reptiles and birds to mammals Marsupials like kangaroo and wallaby have pouches for carrying young

19. Class Mammalia—Eutheriates Eutheria (placenta during gestation) this large group includes all other mammals Many orders and sub-orders: • Herbivora/ Perissodactyla (horses, rhinos) • Carnivora (wolves, dogs, bears, all felines) • Artiodactyla (antelope, cattle, giraffes) • Cetacia (whales & dolphins) • Rodentia (rats and mice) • Lagomorpha (rabbits) • Primates (apes and humans)