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Cold-Blooded
Animals |
Warm-Blooded
Animals |
Definitions |
Their
bodies take on the temperature of their surroundings. (They can't
regulate internal temperatures.) |
They
maintain constant body temperatures despite the temperature of their
surroundings. |
Which
Creatures? |
Insects,
spiders, amphibians, reptiles, fish |
Mammals
and birds |
Energy
Use |
*
Don't require food energy to maintain body temperature.
* Burn more energy in warm weather than cold. (Biological processes
go faster in heat.) |
* Costly!
Humans spend about 75% of our food energy to maintain a constant body
temperature.
* Burn more energy in cold temperatures as they generate heat. (In
hot weather, rid excess heat by sweating or panting.) |
Movement |
Body
slows down in cold temperatures; more active in warmer weather. |
Can
remain active in cold and warm temperatures. |
More
Advantages |
Don't
have to eat as often as warm-blooded animals do. |
*
Bodies function consistently regardless of weather.
* Can
be active at night (nocturnal) and avoid predators. |
More
Disadvantages |
* Speed
of body functions changes with outside temperatures.
* Rely on sun to warm up and protection to stay cool.
* Can freeze fairly easily. |
*
Must eat a lot to stay warm.
* Require insulation from extreme cold/heat.
* Small birds/mammals lose a lot of heat, so must be very active
to stay warm (e.g., hummingbirds). |
Some
Adaptations for Surviving Cold Temperatures
|
*
Burying themselves.
* Slowing down body processes almost to a stop.
* Clustering at night in large groups (e.g., monarchs). |
*
Migrating or hibernating.
* Shivering
(uses a lot of energy).
* Going into torpor: Body temperature drops to
conserve energy. (Chemicals are released to prevent animal from
freezing!)
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