Tuesday, June 07, 2005
Why do elephants have big ears?
Question:
Take it as a given that large animals have more trouble keeping cool than smaller creatures. Why would that be?
Hint:
It's sometimes called the "square, cubed law". As an animal gets bigger in one dimension (say taller) the surface area increases to the square but the volume increases to the cubed (which is much faster). The heat generated inside must escape through the skin (and through breath) but the ratio between surface area to volume keep decreasing as the animal gets larger.
Take it as a given that large animals have more trouble keeping cool than smaller creatures. Why would that be?
Hint:
- Elephants have big ears to keep cool
- These ears are to increase it's effective surface area
- Think of how the volume of an elephant increases for every cm taller versus the increase in area
It's sometimes called the "square, cubed law". As an animal gets bigger in one dimension (say taller) the surface area increases to the square but the volume increases to the cubed (which is much faster). The heat generated inside must escape through the skin (and through breath) but the ratio between surface area to volume keep decreasing as the animal gets larger.
# posted by Scott Kirkwood @ 6:35 PM 
