BIG ANCESTOR By F. L. WALLACE Illustrated by EMSH [Transcriber's Note: This etext was produced from Galaxy Science Fiction November 1954. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] Man's family tree was awesome enough to give every galactic race an inferiority complex--but then he tried to climb it! In repose, Taphetta the Ribboneer resembled a fancy giant bow on a package. His four flat legs looped out and in, the ends tucked under his wide, thin body, which constituted the knot at the middle. His neck was flat, too, arching out in another loop. Of all his features, only his head had appreciable thickness and it was crowned with a dozen long though narrower ribbons. Taphetta rattled the head fronds together in a surprisingly good imitation of speech. "Yes, I've heard the legend." "It's more than a legend," said Sam Halden, biologist. The reaction was not unexpected--non-humans tended to dismiss the data as convenient speculation and nothing more. "There are at least a hundred kinds of humans, each supposedly originating in strict seclusion on as many widely scattered planets. Obviously there was no contact throughout the ages before space travel--_and yet each planetary race can interbreed with a minimum of ten others_! That's more than a legend--one hell of a lot more!" "It is impressive," admitted Taphetta. "But I find it mildly distasteful to consider mating with someone who does not belong to my species." "That's because you're unique," said Halden. "Outside of your own world, there's nothing like your species, except superficially, and that's true of all other creatures, intelligent or not, with the sole exception of mankind. Actually, the four of us here, though it's accidental, very nearly represent the biological spectrum of human development. "Emmer, a Neanderthal type and our archeologist, is around the beginning of the scale. I'm from Earth, near the middle, though on Emmer's side. Meredith, linguist, is on the other side of the middle. And beyond her, toward the far end, is Kelburn, mathematician. There's a corresponding span of fertility. Emmer just misses being able to breed with my kind, but there's a fair chance that I'd be fertile with Meredith and a similar though lesser chance that her fertility may extend to Kelburn." * * * * * Taphetta rustled his speech ribbons quizzically. "But I thought it was proved that some humans did originate on one planet, that there was an unbroken line of evolution that could be traced back a billion years."