Amphibians

1. Amphibians Animals with a double life

2. Primary Characteristic Amphibians have a completely aquatic larvae which transforms into an air breathing, semi-terrestrial adult.

3. Three orders of Amphibians • Caudata: salamanders & newts • Anura: frogs and toads • Apoda: caecilians

4. Characteristics of Amphibians • Undergo metamorphosis (change) • Thin, moist skin • Four legs • No claws on toes • Three chambered heart • Rely on water for reproduction • Ectothermic

5. Thin, Moist Skin • Many amphibians breathe some through their skin • Some salamanders ONLY breathe through their skin • Reptiles have dry, scaly skin

6. Four legs with no claws on toes Reptiles have claws and sometimes no legs

8. Three-chambered Heart • The amphibian heart is inefficient • Oxygenated and deoxygenated blood gets mixed together in the 3rd chamber

9. Why amphibians breathe through their skin • Because the heart mixes blood, they must take in extra oxygen through their skin • The skin must remain moist for gas exchange

10. Water needed for reproduction • Fertilization usually external • Water needed as medium for transporting sperm

11. Body temp changes with the temp of environment Regulates body temp through behavior Become dormant in extreme heat or cold Ectotherms

12. Metamorphosis: Frogs • Frog eggs hatch into tadpoles with: • Fins • Gills • two-chambered heart • Tadpoles grow into adults with: • Legs • Lungs • three-chambered heart

14. Metamorphosis: Salamanders • Larvae have: • Gills • tail fin • Adults: • Have no gills • Have no tail fin • Breath through moist skin or lungs.

15. Larvae vs. AdultSpotted Salamander

16. Caudata: Salamanders • Long, slender body with a neck and tail. • Look like lizards, but have smooth, moist skin and lack claws. • One fourth breathe through skin and have no lungs. • Most have four legs, but some have only 2 front legs.

17. Newts vs. Salamanders • Newts are salamanders that live entirely in water.

18. Local Salamander Species Eastern Red Spotted Newt , Slimy salamander, Blue Ridge two-lined salamander

19. The Hellbender • Largest salamander in North America, and one of the largest in the world. • Up to 29 in. long • Live in rivers and large, swift streams

20. Anurans: Frogs • No tails • Jaws and teeth • Vocal cords capable of producing a range of sound • Use sound to find a mate • Breathe through lungs or skin

22. Frog Songs • Vocal cords capable of producing a range of sound • Vocal cords = band of tissues in the throat • Use sound to find a mate • Frogs can be identified by their songs

24. Dart Frogs • Secrete toxic chemicals through skin as a defense against predators. • Some have enough toxins to kill 10 people • Bright colors act as warning coloration

25. Cane Toads • Imported to Australia to eat beetles • Toxic to fish and animals • Secretes toxin from glands • Causing reduction in wildlife

26. The Beauty of Frogs

27. Frog Leaping • Frogs can jump over 20 times their own length • That is like a person jumping 100 feet!

28. Frog Respiration Breathe through lungs or skin

29. Sensitive to Environmental Changes • Are indicator species for pollution in land, air, or water. • Declining numbers or deformities indicate an unhealthy environment.

30. Frogs: Long, hind legs Smooth, moist skin Toads Bumpy, dry skin Short legs Frogs vs. Toads

31. Local Species: American Toad • Poison glands in paratoid gland behind ears • Squirts milky poison at predators (like dogs)

32. Local Species: Fowler’s Toad • Common in U.S. • Call sounds like the bleat of a sheep

33. Southern Cricket Frog • Dark triangle between the eyes • Call sounds like a series of cricket-like clicks • Tiny – less than 1-1/4 inches long

34. Common Local Frogs Spring Peeper • One of the first songs of the spring • Call is a high-pitched whistle with a trill

35. Eastern Narrowmouth Toad • Sounds like a bleating sheep • Good at burrowing in soil or leaf litter

36. Bullfrog • Largest frog in North America • Eat crayfish, insects, birds, fish • Harvested for legs, which are eaten

37. Green Frog • Sounds like the twang of a loose banjo string • Can be green, bronze, or brown

38. Southern Leopard Frog • Has a light spot in the center of the eardrum • To escape predators, dives in water, makes a sharp turn, and returns to original shore to hide

39. Apoda: Caecilians • No limbs, short or no tail • Tropical • Look like worms • Small eyes and often blind when eyes are covered by skin • Eat earthworms and other invertebrates in soil

40. What is this? 1 2 3 4

41. 5. Which is a newt? A B

42. Quiz • What does the word, “amphibian” mean? • What are the three classes of amphibians? • How are amphibians different from reptiles? • How are amphibian frog larvae different from the adult frogs? • Where do caelilians live? • Why do many amphibians need to have moist skin?

43. Quiz • What is an ectotherm? • What kind of salamander is pictured to the right? • What is the largest salamander in North America? • How are frogs different from toads? • Why are frogs such good indicator species, and what does this mean?

44. Quiz • What kind of amphibian has no legs, often has no eyes, and can be found in tropical environments only? • What is the purpose of the bright skin in a dart frog? • What is the main purpose for a frog song? • What are 3 functions for a cloaca? • What is the function of the tympanic membrane and where is it on the frog? • Where would you find the nictitating membrane?

45. Label the parts

46. 25. Which of the following are amphibians, and how do you know? A C B D

47. Name the species: AB CD