Re: How do whales regulate their body temperature?

Hi Eric,

Whales are Endothermic mammals just like you and me.   Their body 
temperatures are controlled inside the body, and this is one reason why 
they have such a thick layer of insulating blubber.  
However, they do have to contend with cold fins!  To do this they have 
evolved what is called a counter-current exchange system, I'll try to 
explain it... 
Ok so you've got a fin, an artery taking blood to the tip of the fin, and a 
vein bringing the blood back to the body.  
When the blood travels around the tip of the fin it gets cooled as heat 
diffuses into the water, (water is really good for absorbing heat), but, as 
this cool blood returns back to the body it runs alongside the artery 
taking warm blood out to the fin, hereby warming it up again!! Pretty cool 
huh, Arctic Wolves do the same kind of thing with cold blood coming back 
into the body via their feet.

Rochelle.