in genealogy, any person to whom two or more persons claim descent; also, the most recent ancestral form or species from which two different species evolved
We evolved from a common ancestor, and inherited much of the same biochemistry—along with its weaknesses.
At the time, the dingo was semi-domesticated and is believed to be the common ancestor of all breeds today.
At Rome the worship of a common ancestor was the strongest family bond.
It is interesting that bears, dogs, and seals descended from a common ancestor.
They were named after the common ancestor and occupied by his heirs.
They are all the descendants of a common ancestor; they are all sprung from a common stock.
Though our relationship was not close we had been cast in the mold of some common ancestor.
If we went back far enough, we might find a common ancestor.
Can we imagine a common ancestor of Shrews, Hedgehogs, and Moles?
Far back in the days of Poland's greatness they must have had a common ancestor.