The document discusses several means of defense used by amphibians, including producing toxic chemicals from skin glands, mimicry of poisonous species, warning coloration, hiding behavior, rapid escape, urination when grasped, and emitting a distress call when captured. Specifically, it notes that frogs and toads can release bufotenin from parotoid glands or that newts produce the lethal toxin salamandrin.

1. Before we start today’s lesson, there is one fact I want to put out there
before the SLO test.
The tympanic membrane is the ear
drum of a frog/toad.
On some species, such as Bullfrogs,
the size of the tympanic membrane is
sexually dimorphic.
Larger than the eye in males. Smaller than the eye in females.

2. Amphibian DefenseAmphibian Defense

3. ToxinsToxins

4. ToxinsToxins – most amphibians are distasteful to– most amphibians are distasteful to
their predators.their predators.

5. ToxinsToxins – most amphibians are distasteful to– most amphibians are distasteful to
their predators.their predators.
Many species have very poisonousMany species have very poisonous
chemicals that can be released from theirchemicals that can be released from their
skin glands.skin glands.

6. ToxinsToxins – most amphibians are distasteful to– most amphibians are distasteful to
their predators.their predators.
Many species have very poisonousMany species have very poisonous
chemicals that can be released from theirchemicals that can be released from their
skin glands.skin glands.
Amphibians are poisonous, not venomous.Amphibians are poisonous, not venomous.

7. ToxinsToxins – most amphibians are distasteful to– most amphibians are distasteful to
their predators.their predators.
Many species have very poisonousMany species have very poisonous
chemicals that can be released from theirchemicals that can be released from their
skin glands.skin glands.
Amphibians are poisonous, not venomous.Amphibians are poisonous, not venomous.
You must know the following 3 examples ofYou must know the following 3 examples of
toxins produced by amphibians.toxins produced by amphibians.

8. BatrachotoxinBatrachotoxin – a chemical compound– a chemical compound
produced by posion arrow frogs.produced by posion arrow frogs.

9. BatrachotoxinBatrachotoxin – a chemical compound– a chemical compound
produced by posion arrow frogs.produced by posion arrow frogs.
These frogs exhibit bright “warning colors” toThese frogs exhibit bright “warning colors” to
prevent predators from attacking them.prevent predators from attacking them.

10. Toads produce a chemical calledToads produce a chemical called bufoteninbufotenin. This. This
chemical causes increased heart rate and potentiallychemical causes increased heart rate and potentially
heart failure.heart failure.

11. Toads produce a chemical calledToads produce a chemical called bufoteninbufotenin. This. This
chemical causes increased heart rate and potentiallychemical causes increased heart rate and potentially
heart failure.heart failure.
Bufotenin is released from bean-shaped glands calledBufotenin is released from bean-shaped glands called
parotoid glandsparotoid glands located behind toads’ eyes.located behind toads’ eyes.

12. A family of salamanders called newts produce a veryA family of salamanders called newts produce a very
toxic chemical calledtoxic chemical called salamandrinsalamandrin in their skin glands.in their skin glands.

13. A family of salamanders called newts produce a veryA family of salamanders called newts produce a very
toxic chemical calledtoxic chemical called salamandrinsalamandrin in their skin glands.in their skin glands.
SalamandrinSalamandrin is lethal in very small doses.is lethal in very small doses.
Red-spotted Newt (eft). Efts Red-spotted Newt (adult). This
are subadult newts. is an Ohio native.

14. MimicryMimicry is a means of defense utilized byis a means of defense utilized by
amphibians as well as many other animals.amphibians as well as many other animals.

15. MimicryMimicry is a means of defense utilized byis a means of defense utilized by
amphibians as well as many other animals.amphibians as well as many other animals.
Mimicry is a strategy in which a nonpoisonousMimicry is a strategy in which a nonpoisonous
animal that has evolved to look like a similaranimal that has evolved to look like a similar
poisonous species.poisonous species.

16. MimicryMimicry is a means of defense utilized byis a means of defense utilized by
amphibians as well as many other animals.amphibians as well as many other animals.
Mimicry is a strategy in which a nonpoisonousMimicry is a strategy in which a nonpoisonous
animal that has evolved to look like a similaranimal that has evolved to look like a similar
poisonous species.poisonous species.
This mud salamander mimics the toxic red eft. It is native toThis mud salamander mimics the toxic red eft. It is native to
eastern Ohio.eastern Ohio.

17. Aposomatic colorsAposomatic colors

18. Aposomatic colorsAposomatic colors are the “warning colors” that toxicare the “warning colors” that toxic
animals exhibit to inform predators that they areanimals exhibit to inform predators that they are
dangerous.dangerous.

19. Aposomatic colorsAposomatic colors are the “warning colors” that toxicare the “warning colors” that toxic
animals exhibit to inform predators that they areanimals exhibit to inform predators that they are
dangerous.dangerous.
Aposomatic colors areAposomatic colors are
generally bright shadesgenerally bright shades
that stand out againstthat stand out against
the background.the background.

20. Aposomatic colors are the “warning colors” that toxicAposomatic colors are the “warning colors” that toxic
animals exhibit to inform predators that they areanimals exhibit to inform predators that they are
dangerous.dangerous.
Aposomatic colors areAposomatic colors are
generally bright shadesgenerally bright shades
that stand out againstthat stand out against
the background.the background.
Examples:Examples: redred

21. Aposomatic colors are the “warning colors” that toxicAposomatic colors are the “warning colors” that toxic
animals exhibit to inform predators that they areanimals exhibit to inform predators that they are
dangerous.dangerous.
Aposomatic colors areAposomatic colors are
generally bright shadesgenerally bright shades
that stand out againstthat stand out against
the background.the background.
Examples:Examples: yellowyellow

22. Aposomatic colors are the “warning colors” that toxicAposomatic colors are the “warning colors” that toxic
animals exhibit to inform predators that they areanimals exhibit to inform predators that they are
dangerous.dangerous.
Aposomatic colors areAposomatic colors are
generally bright shadesgenerally bright shades
that stand out againstthat stand out against
the background.the background.
Examples:Examples: blueblue

23. Aposomatic colors are the “warning colors” that toxicAposomatic colors are the “warning colors” that toxic
animals exhibit to inform predators that they areanimals exhibit to inform predators that they are
dangerous.dangerous.
Aposomatic colors areAposomatic colors are
generally bright shadesgenerally bright shades
that stand out againstthat stand out against
the background.the background.
Examples:Examples: yellow onyellow on
blackblack

24. Cryptic colorationCryptic coloration

25. Cryptic colorationCryptic coloration allows animals to hide in their habitat.allows animals to hide in their habitat.

26. Cryptic colorationCryptic coloration allows animals to hide in their habitat.allows animals to hide in their habitat.

27. Cryptic colorationCryptic coloration allows animals to hide in their habitat.allows animals to hide in their habitat.

28. Cryptic colorationCryptic coloration allows animals to hide in their habitat.allows animals to hide in their habitat.

29. Cryptic colorationCryptic coloration allows animals to hide in their habitat.allows animals to hide in their habitat.

30. Counter shadingCounter shading

31. Counter shadingCounter shading is a type of cryptic coloration. Frogs thatis a type of cryptic coloration. Frogs that
set at the surface on algae mats are often green dorsally.set at the surface on algae mats are often green dorsally.

32. Counter shadingCounter shading is a type of cryptic coloration. Frogs thatis a type of cryptic coloration. Frogs that
set at the surface on algae mats are often green dorsally.set at the surface on algae mats are often green dorsally.
The same frog’s body is white on the underside.The same frog’s body is white on the underside.

33. Counter shadingCounter shading is a type of cryptic coloration. Frogs thatis a type of cryptic coloration. Frogs that
set at the surface on algae mats are often green dorsally.set at the surface on algae mats are often green dorsally.
The same frog’s body is white on the underside. WhenThe same frog’s body is white on the underside. When
it swims into open water, predators looking up at its bellyit swims into open water, predators looking up at its belly
from below will not be able to see it against the brightfrom below will not be able to see it against the bright
light of the sky.light of the sky.

34. A few amphibiansA few amphibians
have sufficientlyhave sufficiently
sharp teeth thatsharp teeth that
they willthey will bitebite as aas a
means of defense.means of defense.

35. Other means of defense……Other means of defense……

36. Other means of defense……Other means of defense……
1.1. HidingHiding ––

37. Other means of defense……Other means of defense……
1.1. HidingHiding – most small salamanders simply stay– most small salamanders simply stay
hidden beneath logs or rocks.hidden beneath logs or rocks.

38. Other means of defense……Other means of defense……
1.1. Hiding – most small salamanders simply stayHiding – most small salamanders simply stay
hidden beneath logs or rocks.hidden beneath logs or rocks.
2.2. EscapeEscape ––

39. Other means of defense……Other means of defense……
1.1. Hiding – most small salamanders simply stayHiding – most small salamanders simply stay
hidden beneath logs or rocks.hidden beneath logs or rocks.
2.2. EscapeEscape – many amphibians, especially frogs simply– many amphibians, especially frogs simply
leap away from danger.leap away from danger.

40. Other means of defense……Other means of defense……
1.1. Hiding – most small salamanders simply stayHiding – most small salamanders simply stay
hidden beneath logs or rocks.hidden beneath logs or rocks.
2.2. Escape – many amphibians, especially frogs simplyEscape – many amphibians, especially frogs simply
leap away from danger.leap away from danger.
3.3. UrinationUrination

41. Other means of defense……Other means of defense……
1.1. Hiding – most small salamanders simply stayHiding – most small salamanders simply stay
hidden beneath logs or rocks.hidden beneath logs or rocks.
2.2. Escape – many amphibians, especially frogs simplyEscape – many amphibians, especially frogs simply
leap away from danger.leap away from danger.
3.3. UrinationUrination – some amphibians, most notably toads,– some amphibians, most notably toads,
empty their bladder when they are in the graspempty their bladder when they are in the grasp
of a predator.of a predator.

42. Other means of defense……Other means of defense……
1.1. Hiding – most small salamanders simply stayHiding – most small salamanders simply stay
hidden beneath logs or rocks.hidden beneath logs or rocks.
2.2. Escape – many amphibians, especially frogs simplyEscape – many amphibians, especially frogs simply
leap away from danger.leap away from danger.
3.3. Urination – some amphibians, most notably toads,Urination – some amphibians, most notably toads,
empty their bladder when they are in the graspempty their bladder when they are in the grasp
of a predator.of a predator.
4.4. Distress callDistress call

43. Other means of defense……Other means of defense……
1.1. Hiding – most small salamanders simply stayHiding – most small salamanders simply stay
hidden beneath logs or rocks.hidden beneath logs or rocks.
2.2. Escape – many amphibians, especially frogs simplyEscape – many amphibians, especially frogs simply
leap away from danger.leap away from danger.
3.3. UrinationUrination – some amphibians, most notably toads,– some amphibians, most notably toads,
empty their bladder when they are in the graspempty their bladder when they are in the grasp
of a predator.of a predator.
4.4. Distress callDistress call – when captured by or escaping from a– when captured by or escaping from a
predator, most frogs/toads emit a distict call that ispredator, most frogs/toads emit a distict call that is
recognized by their own species as a warning.recognized by their own species as a warning.