Sergeant Stubby was the only war dog to be promoted to sergeant through combat in WWI. He saved his regiment from surprise mustard gas attacks, found and comforted the wounded, and even once caught a German spy by the seat of his pants, holding him there until American Soldiers found him.
16
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
132
Dolphins sometimes have fun by blowing bubbles and creating rings of air underwater, which they then swim through.
17
Sifrhippus was a species of horse about the size of an average duck and roamed North America 56 million years ago.
2
Only 3% of bird species have penises.
0
Cats and dogs can hear ultrasound.
350
The reindeer is the only mammal that can see UV light.
17
A scorpion can hold its breath for up to 6 days.
19