1. Amphibians
Double Life

2. Fossils show that the first amphibians looked like a cross between a fish and a salamander.

3. The word amphibian means “double life”

4. Amphibian Characteristics
Embryos must develop in a moist environment
Amphibians are ectotherms (coldblooded)
Skin is thin, smooth, and moist
Breathe with lungs or through their skin
Most go through a metamorphosis which means change
Tadpoles breathe using gills

5. Metamorphosis of a tadpole into a frog involves the disappearance of its gills and tail and the development of lungs

6. A tadpole obtains oxygen through its gills.

7. Kinds of Amphibians
Caecillians
Salamanders
Frogs
Toads

8. Caecillians Legless Bony scales Most blind Live in tropics
Eat small invertebrates
Looks like an earthworm or snake

9. Salamanders Long tail Four legs Most live under stones and logs
Eat small invertebrates
Some spend entire life in water

10. The four-toed salamander gets all of its oxygen through its skin.

11. Axolotl does not go through metamorphosis.

12. Hellbender is a large salamander found in the New River.

14. Ninety percent of all amphibians today are frogs or toads.

15. Toads
Type of frog
Dry, bumpy skin
Spend less time in water

16. Frogs Smooth moist skin Spend more time in water Sticky tongues
Vocal cords

17. Vocal sacs – a thin-walled sac of skin that surrounds a frog’s vocal cords

18. Copes Gray Tree frog

19. Wood Frog

20. Green Frog

21. Leopard frog

22. Spring Peepers

23. Ecological indicators
Amphibians are ecological indicators because they are sensitive to changes in the environment