Discusses Warm and Cold Blooded animals, differences between them, and how they maintain their body temperature within acceptable limits.

1. Animals are Either Warm
Blooded or Cold Blooded.
What Does It Mean to be Warm Blooded
or Cold Blooded?
By Moira Whitehouse PhD

2. Being warm blooded
The body temperature of a warm blooded
animal stays about the same no matter how
cold or hot it is outside.
On a sunny, hot day a warm blooded animals’
body temperature is the same as it is on a
cold, snowy day .
A warm blooded animal manages this by
using (burning) the food it eats for energy to
keep its body warm.
Warm blooded animals also have special ways
to keep their bodies from getting too warm.

3. Birds and Mammals are warm blooded, and
so are we. Our body temperature stays
about 98.6 degrees F when we are healthy.
If our temperature gets much above or
below that, it might be a clue that we are
getting sick.
For example, while playing
outside on a hot 108°
Texas day, your temperature
would be about 98.6 degrees F.

4. And even while making a
snowman on a very cold
day, your temperature would
still remain the same --
about 98.6 degrees F.

5. Bears are warm blooded mammals like us.
Their body temperature stays at about 90
degrees F in both cold or hot weather
(except when they are hibernating).

6. Other warm blooded animals also have
body temperatures that remain constant
regardless of the outside temperature.
Dogs and cats temperatures vary between
100.5 and 102.5 degrees F.

7. A whale’s temperature stays at about
98.6 degrees F in icy cold water and in
warm tropical water as well.

8. A bird’s temperature is always
about 105 degrees F no matter
where it lives-- in the cold Arctic
or the hot rain forest.

9. All animals change some of what
they eat into mechanical energy
used for movement. Warm blooded
animals also use some of their
food to create heat for keeping
their temperature constant.

10. Being cold blooded
The body temperature of cold blooded
animals, such as
reptiles, amphibians, and fish, becomes
warmer or cooler as the temperature
around them changes.
On a cold winter night, their
body temperature falls.

11. On a hot day in the summer, their
body temperature goes up.

12. A frog is an amphibian, and therefore is cold
blooded. His body temperature is about the
same as his surroundings. If it is 40 degrees F
outside, his body temperature is about 40
degrees F and if it is 95 degrees F outside, his
body temperature is about 95 degrees F.

13. In hot environments, the temperature
of a cold-blooded animal could be
warmer than the temperature of a
warm-blooded animal.
Cold-blooded animals are much
more active in warm environments
but they are very slow moving and
sluggish in cold environments

14. So that we can see the difference in warm
and cold blooded animals we will use an
infrared light, like this one, to view a warm
blooded person and a cold blooded animal.

15. In infrared light, warm objects show
up as warm colors: reds, oranges and
yellows.
Cool objects show up as cooler
colors: blues, greens and blacks.
On the next slide you will observe infrared
photos of a person holding a cold blooded
lizard.
Notice the the colors of the lizard and frog
images and compare them to the image of
warm blooded human holding them.

16. Both the frog and gecko appear
as a darker color than the
human. That means their body
temperature is colder than the
human’s. This is because they
are cold blooded and would be
the same temperature as the
room, whereas the human’s
temperature is always warm.

17. Here we see a the hand of a child as he plays with
a pet snake. It is pretty easy to see which is
warm and which is cold blooded.

18. This lizard
has moved
into the
sunlight to
get warm.
Just as he moves into After he sits in the sunlight
the sunlight for a few minutes
Notice how his body temperature rises as he basks
in the sun. (Compare picture 1 and 2)

19. Turtles are reptiles and are cold-blooded. They spend much of their lives in water
and will bask in the sun on warm days. When the weather turns cold, turtles will
often burrow into the soil until warm weather returns.
These turtles have just walked out of pool of cool water. Notice how cold they still are.
Notice how warm this turtle has become after basking in the sun!

20. From our study of animal needs, we
might remember one of a warm-blooded
animal’s needs is to keep its body at a
certain temperature.
If the body temperature gets too high or
low, an organism will likely be sick and
may even die.

21. If your temperature is higher than 100
degrees F or lower than 93 degrees F, it
probably means that you are sick.

22. Temperature too high

23. Or too low

24. The range of body temperatures for a
cold-blooded animal is much greater
than for a warm-blooded animal.
However, if their temperature gets
outside of that range, too hot or too
cold, they will also die.
So the body temperature of an animal
in either group, warm or cold-
blooded, has to stay within a certain
range.

25. One of an animal’s basic needs is to keep
its body in the right temperature range.
But how do they manage that, how do
they keep warm or cool?
How an animal keeps its temperature at
the right level mainly depends on whether
it is warm or cold-blooded.
First, we will look at how warm
blooded animals stay cool when the
temperature outside gets above their
comfort level.

26. To cool off many warm-
blooded animals use the
process of evaporating
water.
When water evaporates
from the animal’s body it
absorbs heat energy and
cools the animal’s body.
This is why you feel so
cold when you get out of
the swimming pool on a
hot summer’s day.

27. One way warm blooded animals keep their
bodies at a constant temperature in hot
weather is by panting. Fast moving air over
the animal’s tongue evaporates water
cooling the tongue and the animal.

28. Animals like pigs wallow in mud when they
are hot. The water evaporates and lowers
the pig’s body temperature.

29. Some mammals sweat bead of
sweat
when they get too
hot. Primates, such as
humans, apes and
monkey, have sweat
glands all over their
bodies. Dogs and cats
have sweat glands
only on their feet.
How would sweating
cool an animal?

30. Mammals who live in water like whales
don’t need sweat glands. To cool
off, they simply swim to a cooler spot in
the ocean.

31. Many mammals and birds that live in
hot climates avoid the summer heat
by coming out to look for food at
night when it is cooler. These
animals are called nocturnal.

32. Big cats such as jaguars and cheetahs are
nocturnal. They keep cool by lounging in
the daytime and hunting at night. During
the day, they rest under the shade of a big
tree.

33. Some mammals who live in hot climates
lose heat through their big ears.

34. Even Sooty Tern chicks know to get in the
shade of a bigger bird (a Black Footed
Albatross) when it gets too hot.

35. Like cats and dogs, birds also pant to get rid
body heat. But it is not through
evaporation that they lose heat. They
breathe very quickly, letting the cooler air
pass through their lungs which carries heat
away from their bodies. A bird standing
with its mouth open on a hot day is
probably panting.

36. So mammals and birds, the two groups
of warm blooded animals, have many
different ways to keep cool. Can you
remember some of them?
Now let’s consider how warm
blooded animals keep warm when
it is cold outside.

37. Land mammals that
live in cold places
often grow a thick
layer hair or fur
during the winter
that keeps the heat
inside their bodies.
Their fur or hair acts
like a blanket.

38. In the summer when the weather
warms up, these animals lose that
thick layer of hair or fur.

39. Whales and walruses live in cold
ocean water and have a layer of
blubber (fat) to keep them warm.
whale
blubber

40. A polar bear has both a thick fur coat
and a layer of blubber (fat) which
insulate its body.

41. A bird’s feathers, like the mammal’s hair
and fur, provide remarkable insulation
from the cold. Many birds grow extra
feathers in the fall to keep them warmer
in the winter. They lose this feathers come
spring.

42. Some birds cannot survive cold winter weather.
These species migrate to locations with
warmer temperatures and more food.
bird migration routes

43. Some warm blooded mammals such as
ground squirrels, bears and bats cope with
the cold by hibernating, a deep winter
sleep.
In the fall, these
animals eat a lot of
food which they
store as fat.

44. When cold weather comes mammals that
hibernate find shelter in places such as holes in
rocks or caves.
When hibernating, the
animal’s body temperature
drops, and both its
heartbeat and breathing
slow down. It uses hardly
any energy to stay alive.
This is when the animal
lives off the stored fat that
was packed on in the fall.

45. Some mammals and birds that live in very
cold climates huddle together to keep
themselves warm.

46. So far we have talked about how warm-
blooded animals keep themselves warm
when their environment is cold and cool
when it is hot.
But what about cold-blooded animals?
What do you remember about cold-
blooded animals and how they are
different from warm-blooded animals?

47. Cold blooded animals, you should
remember, have a body temperature that
is the same as the temperature in their
surroundings.
To warm or cool their bodies, they must
change their surroundings.

48. Reptiles like lizards, turtles and crocodiles bask
in the sun to warm up .
After a cool night, lizards, turtles and snakes
climb on to a rock or log where they lie in the
sun which warms up their body.

49. When the day warms up and a reptile becomes
too warm and needs to lower its body
temperature, it finds a shady area under a
rocks to cool down or log or slips into the cooler
water.

50. Reptiles like lizards and snakes that live
in the hot desert stay in underground
burrows during the hot summer days
l
coming out at night to hunt for food
when it is cooler.

51. Amphibians like frogs and toads use the same
techniques to warm up and cool down.
In the spring and
summer they lie on
the bank of a lake or
river absorbing the
rays of the Sun
thereby warming up
their bodies.
When they need to
cool down, they slip
into the cool water.

52. They may also simply swim into the
warmer top layer of water in a pond to
heat themselves up a bit. When they get
too hot, they typically move to a cooler
place, sometimes even going underground.

53. But how do reptiles and amphibians
stay warm in places where the
temperature drops below freezing
during the winter time.
Generally during the winter, they
burrow underground and hibernate
below the level that the ground
freezes. Their heart rate and
breathing slow down. When spring
comes they emerge.

54. Here we see where snakes and lizards
have gone underground into burrows
or caves to keep away from the freezing
temperatures.

55. One amazing
hibernation story
is the Garter
Snakes of
Manitoba, Canada
.
Thousands of Red sided garter snakes enter
limestone caves to seek shelter below the
frost line in an area that can experience harsh
winter weather. This is the largest gathering
of snakes anywhere in the world.

56. When the cold weather comes during
winter, frogs, toads, and river turtles bury
themselves in mud or soil and “hibernate”. In
the spring when the sun warms the mud, out
they cometo absorb the heat of the Sun.

57. Some frogs that live in very cold places
can’t dig down far enough into the soil to
avoid the ice and actually freeze during
the cold winter months.
When the weather
gets warmer, the
Frozen frog
frog’s body melts
and after some
repairs to its body
comes alive.

58. What about the other cold blooded
group of animals—fish?
For fish it is easy—they just swim to
a layer of the water where the
temperature is right for them.
Fish who live in areas where the
winters are cold move to deeper
waters during the colder months or
migrate to warmer waters.

59. So remember that if an animal is to
survive, it must keep its body
within a certain range of
temperatures.
If its body temperature becomes
too high or too low, an animal will
become sick or die.

60. •In this presentationwarmhave
The differences between we and
cold-blooded animals.
discussed the following points:
• How warm-blooded animals keep warm
when it is cold outside.
• How warm-blooded animals cool down
when it is hot outside.
• How cold-blooded animals warm up when
it is cold outside.
• How cold-blooded animals cool down
when it is hot outside.
• How cold-blooded animals survive cold
winter temperatures.

61. Let’s go back over each point and see
what you can remember.
What is the difference between a warm
and cold blooded animal?
What two animal groups are warm blooded
and which three are cold-blooded?

62. • How do warm-blooded animals (mammals
and birds) keep warm when it is cold outside?

63. • How do warm-blooded animals (mammals
and birds) cool down when it is hot outside?

64. • How do cold-blooded animals warm up
when it is cold outside? Cold-blooded
animals include reptiles such as
turtles, lizards, snakes, crocodiles and
alligators, amphibians such as frogs and toads
and fish.

65. • How do cold-blooded animals cool down
when it is hot outside?
(Cold-blooded animals include reptiles such as
turtles, lizards, snakes, crocodiles and
alligators, amphibians such as frogs and toads and
fish.)

66. • And lastly, how do cold-blooded animals
survive cold winter temperatures?

67. Bye!
Stay cool!
(or maybe warm!)