The sound of a tiger's roar can travel a distance of up to 2 miles (~3 km).
255
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9
Gorillas can catch human colds and other illnesses.
205
The difference between antlers and horns is that antlers are shed each year and are made of bone while horns are kept for life and are made of living tissue and bone with a sheath that is very similar to human finger nails.
10
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