Diverse Vertebrate Animals: Characteristics and Classifications

1. Vertebrate Animals Bio I DOMAIN- Eukarya KINGDOM- Animalia • PHYLUM- Chordata • SUBPHYLUM- Vertebrata • CLASS- 7 different • ORDERS- 10 Placental mammals

2. Characteristics of all Vertebrates • Backbone • Endoskeleton • Distinct Skull • Bilateral Symmetry • Closed Circulatory System & chambered heart

3. Types of Egg Layers • Ovoviviparous = eggs are fertilized inside the parent and hatch inside the parent and are born live • Oviparous = eggs are laid in a nest or in the ground and hatch • Viviparous = internal fertilization with live born young (as soon as the egg is fertilized, it becomes an embryo and develops as a fetus).

4. Class Agnatha Hagfish and lampreys • Jawless & finless • Skeleton of cartilage • Reproduce sexually • Gills • Oviparous • Lamprey – an ectoparasite Hagfish – a detritivore

5. Class Chondrichthyes • Ex. Sharks and rays • Endoskeleton made of cartilage • Paired fins • Jaws • Lateral line system (for sensing vibrations in water—like an “ear”) • Scales • Oviparous, Ovoviviparous, or Viviparous—depends on species

6. Class Osteichthyes Tuna, perch, bass, clown fish, eels, seahorses, goldfish, catfish, etc…. * One of the most successful groups on Earth – ever! • Endoskeleton made of bones • Swim bladder • Usually, external fertilization & oviparous (think caviar) • Lateral line system • Scales different from those in sharks

7. Class Amphibia Frogs, toads, salamanders, and newts • Ectotherms • Need H2O for breeding • Metamorphosis (tadpole  frog) • Gas exchange through moist skin & mouth; primitive balloon-like lungs • External fertilization • Oviparous • 3-chambered heart • Many have chromatophores in the skin for coloration, as well as poison glands for defense

8. Class Reptilia turtles, snakes & lizards, crocodiles • Ectotherms – bask and hide to regulate temperature* • Scaly, waterproof skin • Respire through lungs only** • Internal fertilization • Oviparous, ovoviviparous, viviparous (depending on species) • 3 or 4 chambered heart • Nitrogenous waste is a paste rather than a liquid for water conservation; uric acid • Extinct reptiles include dinosaurs and pterosaurs, which dominated the Earth during the Triassic period

9. Class Aves Birds • Endothermic • Internal fertilization • Oviparous • Beaks and claws modified for specific niche • Classified as reptiles by many taxonomists • Digestive system modified for diet, including crop & gizzard

10. Aves modifications for flight: • Only organism with feathers (modified scales) for flight and insulation • Hollow bones - make bird lightweight • Front limbs modified into wings • Air sacs to aid in breathing at high altitudes • Unique muscle tissue for sustained, intense use

11. Class Mammalia Humans, bears, pigs, horses, dogs, cats, whales, elephants, mice, koalas, platypus • Endothermic – hair and layer of fat aid in conserving heat • Hair –aids in insulation • Mammary glands – produce milk to feed offspring • Internal fertilization • 2 species of monotreme; oviparous • Marsupials and placentals are viviparous

12. Three Categories of Mammals • Monotreme- egg laying mammal • Marsupials- young develops outside the body in a pouch • Placental- young develops in uterus

13. 3 categories of mammals • 1. Monotremes • - mammals that lay eggs, have hair, and produce milk with mammary glands • Ex. Echidna (eh-kid-nuh) and platypus

14. Marsupials • - embryo develops in a uterus with a placenta • Immature fetus is born into a pouch called a marsupium. • All marsupials live in Australia with the exception of the opossum, which can be found in the Americas.

15. Placentals • Placental mammals develop in a uterus attached to a placenta until at a comparably advanced stage of development • Widespread on earth – found in every major biome, including marine, arctic, and tundra. • Many orders of placental mammals. 10 discussed as follows:

16. Orders of Placental Mammals Rodentia- razor sharp teeth (rats, squirrels) Lagomorpha- fused hind leg bones (rabbits) Chiroptera- flying mammals (bats) Carnivora- eat meat (lions, tigers, wolves) Cetacea- Blow holes to breathe (dolphins, whales) Insectivora- eat insects (moles, shrews, hedgehog) Artiodactyla- even # of toes (cows, sheep, goat, pigs, hippos, camels) Perissodactyla- odd # of toes (horse, zebra, rhino) Proboscidea- trunks (elephants) Primates- opposable thumbs (apes, monkeys, humans)