Scientists are pretty sure that Saccorhytus coronarius is an ancestor of lancets, sea squirts, fish, amphibians, reptiles, dinosaurs, and mammals: including us.
Much more recently, about 3,660,000 years back, five Australopithecus afarensis strolled across volcanic ash. One of them was "astonishingly larger" than any other A. afarensis we know of. Exactly what that means isn't, I think, clear. Not yet.
More at A Catholic Citizen in America.