I don't mean the "first generation." Rather, I mean "ancestor." The term "MRCA" says "most recent common ancestor." .Does an estimated MRCA of 4 (for example) refer to a likely great grandparent, or does the term refer to a likely great grandparent? Of course there are scientific issues involved in the topic, but I am hoping to limit my question to the word "ancestor." Is it being used as a synonym for "generation" or not? I suspect that it is used loosely to refer to one's own generation as well, but since it does not say that, I wanted to be sure. Thanks. ) : )