Americans are always leaving some place behind; departures are in our ancestral genes.

This domain is probably derived from a frame-shifting mutation in an ancestral gene.

The idea is to run each gene tree backward to the ancestral gene at the root of the tree.

"We are looking for ancestral genes, to turn them back on again to make a bird more like a dinosaur," Horner explains.

This provides further evidence that the prostanoid receptor family arose from a common ancestral gene.

He is known for resurrecting ancestral genes and tracing the mechanisms by which proteins evolve new functions.

Taken together, the two mutated genes provide the same set of functions as the ancestral gene (before duplication).

It is also suggested that mir-433 and mir-127 are likely to have originated form a common ancestral gene.

However, mammalian enzymes with different functional activity may have evolved by combining elements from several bacterial ancestral genes.

Using kinship analysis he showed ancestral genes could partly explain some "clusters" but were of small effect at a population level.