When cats are happy, they may squeeze their eyes shut.
10
Some species of fish have voices!
81
A rodent's teeth never stop growing.
16
How does a shark find fish? It can hear their hearts beating.
31
Humans and dolphins are the only species that have sex for pleasure.
61
Mexican Jumping Beans jump because of moth larvae inside them.
29
Dogs and cats, like humans, are either right or left handed... or is that paws?!
34