Hox genes and evolution
Your Hox genes are very similar to those of other animals - even a fruit fly's. Hox genes have remained much the same during animal evolution, because they are so important. Even a slight change in a single Hox gene could have a drastic effect on an animal's body. Different animals may have evolved in this way, for example, snakes may have evolved from lizards by losing the Hox gene for making legs.