Genetic ancestor

Galapagos Graphics: Sketch of Darwin's Finches by John Gould from 'Voyage of the Beagle'

All Galapagos finches share a genetic ancestor

A Genetic Ancestor is an individual several generations earlier (ancestor) that is genetically connected to another individual (descendant). Genetic descendants will have inherited genetic information from their ancestor and will therefore exhibit similar physical characteristics. All 14 species of finches are descendants from a single genetic ancestor.

Glossary of Galapagos