"Imagine, if you will, a three-foot Teaser fish who lived, cavorted, made love and finally died somewhere in the Sea of Tethys. Nothing and no one took notice as this obscure creature's body slowly sank to the red mud of the seabed. The unmarked grave was covered over with sediments which hardened into sandstone and left a thin film of carbon. It was this trace of carbon that etched and outlined the Teaser's tissue and bone structure into the surrounding strata. The years passed and turned into millenniums. And the millenniums became eons, until one warm spring day, two hundred million years later, a farmer in the Austrian town of Neunkirchen struck his plow against a hard surface. And presto, our Teaser fish, though now a near perfect fossilized version, once again returned to the light." Gunn hesitated and ran his hand through a head of thinning hair. His face looked drawn and tired, but his eyes burned with excitement as he spoke of the Teaser. "One vital element you must remember; when the Teaser died there were no birds and bees, no hair-bearing mammals, no delicate butterflies, even flowers had not yet appeared on the earth."

Pitt studied the photograph of the fossil again. "It doesn't seem possible that any living thing could survive this long without going through drastic evolutionary changes."

"Incredible? Yes; but it has happened before. The shark has been with us for three hundred and fifty million years. The horseshoe crab has existed virtually unchanged over two hundred million years. Then, of course, we have the classic example: the coelacanth."

"Yes, I heard of it," said Pitt. "That was the fish believed extinct for seventy million years until they began to be found off the coast of east Africa."

Gunn nodded. "The coelacanth was a sensational and important find at the time, but nothing compared to what the scientific world would gain if we could drop a Teaser in its lap." Gunn paused for a moment to light another cigarette. His eyes betrayed the gleam of total absorption. "The whole thing boils down to this; the Teaser could be an early link in the evolution of mammals, and that includes man. What I didn't tell you was that the fossil found in Austria shows definite mammal characteristics in its anatomy. The protruding limbs and other features of its internal organs place it in a perfect evolutionary line to advance in a general pattern toward the development of humans and animals."

Pitt idly glanced at the pictures again. "If this so-called living fossil is still floating around in its original form, how could it evolve into an advanced stage?"

"Any plant or animal species is like a related family," Gunn replied. "One branch may produce offspring who are uniform in size and shape, while the cousins over on the other side of the mountain produce a race of giants with two heads and four arms."