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
The reindeer is the only mammal that can see UV light.
17
Parrot parents "name" their children with a signature call.
112
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9
Cats are one of the only animals to domesticate themselves and approach humans on their own terms.
20
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14