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. Vertebrate Chordates-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 Mammals Prototheria 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)