A rodent's teeth never stop growing.
16
Mosquitoes prefer certain blood types, and people with the “O” blood type are more likely to get bitten.
12
A crocodile cannot stick out its tongue.
1k
A bird 'chews' with its stomach.
33
The lifespan of mammals is about 1 and a half billion heartbeats.
127
Lake Nicaragua in Nicaragua is the only fresh water lake in the world that has sharks.
28