1. Chapter 5: Vertebrates
What is a Vertebrate?

2. What is a vertebrate? Animals with backbones.
Only about 5% of animal species.
Endoskeleton: internal support system that grows along with the animal.
Muscles, digestive system, respiratory system, circulatory system, and nervous system.

3. What is a vertebrate?
Named for specialized bones called vertebrae, also known as the backbone.
We will be learning about fish, amphibians, reptiles, birds, and mammals in this chapter.

4. Chapter 5: Vertebrates - Chordates
Fish

5. Most vertebrates are fish.
More than 20,000 species.
Live in nearly all aquatic environments.
They have adapted to survive many environments.

6. Most vertebrates are fish.
Most move by using muscles and fins to push their bodies through water.
Most also have a swim bladder, which allows them to regulate how high or low they float.
Sensory organs, including eyes.
Lateral line: allows fish to sense vibrations from other objects without seeing/touching them.

7. Fish

8. Most vertebrates are fish.
Fish remove oxygen from water by gills.
Made of many folds of tissue and filled with blood.
Water is brought in through the mouth, pushed over the gills, and then removed through the gill slits.

9. Jawless Fish Most similar to the first fish on Earth.
Simpler bodies- tube-like shape and no stomach.
They have no jaw, but do have teeth that cannot chew.
They get food by latching onto animals and sucking out flesh and fluids.
Lampreys and hagfish

10. Jawless Fish

11. Cartilaginous Fish Sharks, rays, and skates.
Skeletons are made of cartilage, not bones.
Most eat small animals such as mollusks and crustaceans.
Rays eat by pulling animals out of the sand on the ocean floor.

12. Cartilaginous Fish

13. Bony Fish
Most fish (96%) are bony – tuna, flounder, eels, goldfish, etc.
Skeletons made of hard bones, usually covered by bony structures called scales.
They have jaws with teeth and several pairs of fins.

14. Bony Fish
There are several adaptations of these fish for survival in their environments.
In the tropics, fish are brightly colored to fit in with the coral.
In other areas, bright colors would draw too much attention to the fish.

15. Bony Fish

16. Fish Life Cycles Most reproduce sexually.
Female fish release eggs into the water when a suitable male is there to fertilize them.
After fertilization, the eggs are left on their own (usually) to hatch.

17. Fish Life Cycles
Most fish eggs are surrounded by a soft egg case that allows water to move through it, giving the embryo water and oxygen.
The yolk provide nutrition to the growing embryo.
Very few eggs actually hatch into mature fish; they are usually eaten before they hatch.

18. Chapter 5: Vertebrates
Amphibians

19. Amphibians The first group of vertebrates to live on land.
Took millions of years for adaptations to occur allowing this group to evolve.
Frogs, toads, and salamanders

20. Amphibians Two pair of legs Lay eggs in water
Obtain oxygen through moist skin; many have lungs
Sensory organs adapted for life on land.

21. Amphibians
Their skin functions only when it is moist, so they live in moist environments.
Some are most active at night when there is more moisture near the ground, while others live mostly underground.

22. Amphibians Reproduce sexually.
Female lays eggs in water, male fertilizes the eggs, and then they are left to hatch on their own.
The yolk in the egg provides nutrition, and because there is no hard covering, they can get water and oxygen from surroundings.

23. Amphibians – Life Cycle
When egg hatches, the amphibian is called a larva.
These are called tadpoles for frogs/toads, and act like small fish.
Gills
Eat algae
Move by swimming with tails

24. Amphibians – Life Cycle
After a few weeks, lungs begin to develop and the digestive system changes.
Develops legs, loses its tail, and its head changes shape.
Gills stop working, tongue is used to capture/eat small animals, and moves on to the land.
Some stay in or near water, others move around.
Frog Life Cycle

25. Chapter 5: Vertebrates
Frog Anatomy

26. The Frog Divided into a head, short neck, and trunk.
The head contains the brain, mouth, eyes, ears, and nose.

27. The head – external
When you look at the head from the outside, you should be able to identify the following:
Eyes
Mouth
Nostrils (near mouth)
And tympanum (ear drums)
located behind the eyes.

28. The head – internal Inside the mouth, you should see: Teeth Tongue
Internal nostrils (nares)
Esophagus opening
Glottis
Eustachian tube openings

29. The head – internal
Inside the mouth, you should see:

30. The head – internal
Inside the head, is the brain. This will be difficult to get to.

31. The trunk – internal The heart The lungs The kidneys The stomach
The liver
The small/large intestine
The spleen
The pancreas
The gallbladder
The urinary bladder
The cloaca
The ureter
Fat bodies
And reproductive organs: ovaries/ oviducts, testes

32. The trunk – internal

33. The trunk – internal

34. The trunk – internal

35. The trunk – internal
Part 1
Part 2

36. Chapter 5: Vertebrates
Reptiles

37. Reptiles Survive in hotter, drier climates. Two pair of legs
Tough, dry skin covered by scales
Get oxygen through lungs
Sensory organs for land
Lay their eggs, in shells, on land

38. Lungs Born with lungs; do not use skin to take in O2.
Takes in oxygen through mouth/nostrils and moves it into lungs;
Exhales carbon dioxide

39. Skin Dry and tough, covered with scales made from keratin. Waterproof
Protects from environment and predators

40. Eggs
Eggs contain everything an embryo needs: water, nutrients, gas exchange, waste storage.
Membranes separate the internal parts, which are covered by hard shell.
Reproduce sexually.
After fertilization, the hard covering forms around each egg while still inside the female.

41. Eggs The female chooses a place on land to lay the eggs.
Some guard their eggs and care for offspring once they hatch (alligators).
Most leave their eggs to hatch on their own.
Once hatched, they look like small versions of the adult.

42. Body Temperature – Amphibians and Reptiles
Ectotherms: body temps change with the environment.
most can move/respond more quickly when warm, so they warm themselves in sun.
Many can live a long time without consuming much food.

43. Body Temperature Body stops functioning when too hot or too cold.
Some are able to adapt to temperature by living in certain environments.
Most live by water, which can be used to cool them down.

44. Chapter 5: Vertebrates
Birds

45. Birds About 10,000 species that live all around the world.
Feathers and a beak
Four limbs – pair of legs and pair of wings
Eggs have a hard shell

46. Endotherms Endotherm: animals that maintain a constant body temp.
Can stay active in colder climates because they have adaptations for producing more body heat from food.
They need to eat a lot; birds in cooler climates need to eat more to produce more heat.

47. Controlling Body Temp
Soft feathers (down) keep warm air close to their bodies and act as insulators.
Other feathers, contour feathers, cover their down and are usually water-resistant.
Birds shiver, like humans, to generate heat.
They can fluff their feathers to lose heat or move to shaded areas.

48. Most can fly.
Birds first appeared about 150 million years ago, and are thought to be descendants of reptiles with adaptations to fly.
Most can fly – ostriches and
penguins cannot.
Birds have many adaptations that took millions of years for them to be able to fly:

49. Adaptations
1. Endoskeleton: some bones are fused together without joints, making them light and strong.
2. Wings/Feathers: flight feathers on the wings are specialized for lifting and gliding; feathers are strong to push through air.

50. Adaptations
3. Respiratory System: breathe using a system of air sacs and lungs; oxygen is constantly moving through the body.
4. Hollow Bones: many of the bones are hollow with crisscrossing structures; provides strength and reduces weight.
Birds also have beaks and gizzards instead of heavier eating structures.

51. Adaptations

52. Benefits of Flight Easily to see and get food.
Migration is possible in the cooler months
Easily escape danger

53. Reproduction Reproduce sexually
Usually males display traits (singing, colorful feathers, fighting, etc.) and the female selects her mate.
Eggs are fertilized and then laid; hard shell.
Eggs must be kept at constant warm temp, so birds sit on their eggs – incubation.

54. Caring for Offspring
In some species, the eggs hatch before the bird is developed fully. Male and female parents both care for young.
In most species, the female primarily cares for the young because they are more fully developed.

55. Chapter 5: Vertebrates
Mammals

56. Mammal Characteristics
Have hair at some part of their lives
Teeth specialized for consuming food
Produce milk, which is fed to their young

57. Mammals are Endotherms
Use some of the food they eat to make body heat.
Have a few adaptations for controlling body temp. For example:
Hair
Body fat

58. Hair Allows mammals to control how warm/cold their body is.
Most have two types: soft, fluffy under hairs to keep in heat, and water resistant guard hairs.
Specialized hairs – whiskers and quills, for example.

59. Body Fat Aquatic mammals don’t have much hair
They have a layer of fat, blubber, to help maintain body temp.
Located between skin and muscles
Can also be a storage place for energy – used for mammals that hibernate.

60. Reproductive Adaptations
Reproduce sexually
Offspring develop inside female body; an organ called the placenta transports nutrients from the mother to the offspring.
The time offspring spends inside its mother is called gestation; it changes from species to species.
See chart on page 186.

61. Reproductive Adaptations
Some mammals do not fully develop inside of the mother.
duck-billed platypus and some anteaters hatch from eggs.
Marsupials develop inside of the mother, but then move to finish developing inside of a special pouch
Kangaroos, opossum

62. Raising Young
The first food for mammals is milk, which is produced in the mammary glands.
In most species, only the females care for the young.
Humans care for their young longer than other species; most species are with their young for only a short period.