One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
An average cat has 1-8 kittens per litter and can have 2-3 litters per year. During her productive life, one female cat could have more than 100 kittens. A single pair of cats and their kittens can produce as many as 420,000 kittens in just 7 years.
10
Parrotfish make themselves a kind of mucus 'sleeping bag' which masks their smell from predators and keeps parasites away.
4
There's a young hippo and a 130+ year old tortoise in a Kenyan wildlife preserve who are best friends and they even sleep and play together.
40
The two oldest cats on record lived to 38 and 34 years old, both were owned by the same owner and lived off a diet of bacon, eggs, broccoli and coffee.
12