Identical twins are rare, but monoamniotic identical twins, who share the same amniotic sac and placenta, are even more so—they make up just 1% of all twin pregnancies. That's why everyone is so excited that a lucky Ohio mom gave birth Friday to a pair of "mono mono" twins who clutched each other's hands as doctors held them up.

An Irish farmer claims to have accidentally bred an unusual sheep-goat hybrid, commonly known by the much cuter name "geep."

The latest arrival at San Diego Zoo Safari Park is a healthy newborn gorilla delivered through caesarian section. The procedure is rare for animal births, but in this case, it was an emergency.