Beavers have 6 of these on their heads (in 2 sets of 3); 1 is transparent & helps in swimming underwater
These animals are active all winter, swimming and foraging in their 
ponds... [DOC] [TLE] Field Guide/Mammals/United States/Minnesota - Wikibooks, open ... [PAR] Notes: The American Beaver has adapted to have its ears and nose close when 
.... Activity: These ground squirrels come up when the sun is up and the earth is 
warm ..... to give birth after 44 days and have about 1-6 babies but 1-3 only 
makes it alive.