first，small，twin，easy，be，give，part |
Do you have twin friends or classmates? It's to see human twins，but it is hard to find animal twins. So far，it is said that only humans and nine—banded armadillos（九带犹徐） birth to twins，the BBC reported.
Now，we can add one more animal to the list—dogs!
Cullen and Romulus are the world's twin dogs，said the BBC. They were born in an animal hospital South Africa. A animal doctor named Kurt de Cramer delivered （接生） the twins. The twin dogs were than other dogs at birth. But now they are growing bigger and better.
The dogs share the same DNA. But Cullen and Romulus still have some small in the white markings（纹理） on their feet and other of their bodies. It's nothing special，said De Cramer. Human twins sometimes also have different freckles（斑点）and fingerprints.
Cullen and Romulus are the first dogs we have found. But maybe there lots of others in the world. They are waiting for us to find them.
