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
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
Dolphins have names for one another.
18
The cat brain weighs about 30g.
167
Worker bees must visit around 4,000 flowers in order to make one tablespoon of honey.
5