As part of a worldwide conservation effort, scientists at the National Zoo breed endangered species for the purpose of re-introducing them to nature. The National Zoo is truly a park full of wild animals, but it is also a reminder that humans don’t rule the earth; we share it. The National Zoo is a park full of wild animals. Many of the animals on display are critically endangered in the wild. Some are even extinct in nature and only exist in captivity. Some of the Zoo’s most important challenges involve engaging visitors and reminding them that we are all connected to what goes on out in the wild.