Rats breed so quickly that in just 18 months, 2 rats could have created over 1 million relatives.

The hydra, which is related to the jellyfish, can grow its body back in a couple of days if it is cut in half.

The United Parcel Service shipped the killer whale Keiko (star of Disney movie "Free Willy") from Mexico City to Newport, Oregon in 1998.

AMAZING FACTS