When cats are happy, they may squeeze their eyes shut.
10
Parrotfish make themselves a kind of mucus 'sleeping bag' which masks their smell from predators and keeps parasites away.
4
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
It has been calculated that a single breath from a mature blue whale can inflate up to 2,000 balloons.
492
The Lion's Mane Jellyfish is the largest jellyfish in the world. They have been swimming in arctic waters since before the dinosaurs (over 650 million years ago).
12
15% of snails survive digestion by birds and are found alive in their droppings, potentially leading to the spread of snail populations.
1