A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Cats and dogs can hear ultrasound.
350
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
The colossal squid has the largest eyes in the world.
4
On some poorly researched trivia lists it is stated as a fact that a pregnant goldfish is called a twit. This is not true as goldfish lay eggs.
71
The most expensive dog in the world is the Tibetan Mastiff; worth $1.5 million.
2