"Second, this creature lands on our world and manages to get himself killed. Perhaps not so farfetched.
"Third, that he was traveling completely alone. That seems a ludicrous assumption unless we allow for truly space-operaticlevel technology—and in that case, what was he doing protecting himself with what amounts to a fancy shotgun? Or, if he wasn't alone, that his fellow beings didn't bother to retrieve his body. Human cultures do not just leave bodies to be savaged by random creatures, and I find it hard to believe that alien ones would either. Or, of course, something else killed off his fellows coincidentally before they could interfere or retrieve the body.
"Fourth, that he managed to injure most if not all of his attackers— but not swiftly enough to keep from being killed himself, though the injuries he dealt made them expire just a short distance from him. Close enough that they could all be found together in a single death scene, sixty-five million years later.
"Fifth, that of all the untold trillions of death scenes across the entire world over the past hundreds of millions of years, it was this— already utterly improbable—death scene that just happened to be one of the very few preserved as a fossil."
Having run out of fingers, he lowered his hands. "And, finally, to add insult to statistical injury, you want us to believe that all this just happened to occur at the very moment the asteroid or comet struck the Yucatan. So that all of these perfectly preserved corpses ended up literally sitting on the K-T boundary."
He gave Helen a level stare. Not an unfriendly one, no. But it was just as disconcerting today as she remembered that stare being when she was a young graduate student.
"Helen," he said softly, "I just demolished Pinchuk by showing the mathematical absurdities that his scheme would entail. I can assure you—this is my own field of expertise, as you know—that if I subjected your theory to the same sort of mathematical scrutiny, the results would be several orders of magnitude worse. I did a rough estimate, as it happens, the moment I finished your paper. I stopped once I realized that your theory is statistically more improbable—far more improbable, as a matter of fact—than the existence of dragons and unicorns."
Helen couldn't argue with the statistical improbabilities involved. She was not an expert on the math involved, the way Glendale was, but she knew enough to know that he was right. She'd been bothered all along by the cumulative series of unlikely coincidences, and had no good explanation for them herself.
Still . . .
Helen was a fieldworker, not a theoretician like Glendale.
"But facts trump probability, don't they, Nicholas?"
"Certainly, Helen. Facts always trump theories. And if you had found that our mysterious friend had a fossilized repeating shotgun on his person, I would have conceded immediately—and then wracked my brains trying to figure out how to explain the improbabilities involved. In this case, however, I think what you are seeing is something still very improbable, but at least a couple of orders of magnitude more likely than fossilized aliens. That is, a creature of a previously unknown phylum which, through quite amazing probability events, has not had any of its precursor forms discovered previously.
"Or," he added, "which I personally think is what we'll find, that such fossils have been found but weren't recognized for what they were. Helen, I suspect that if you could take a few years and search through the miscellaneous fossils in the New York Museum of Natural History and similar places, you'd find some misfiled shells that are, in fact, parts of precursors to your Bemmius. Such things happen often enough, as you well know. Look how long it took before we finally realized what the conodonts were. This is just an extreme version of it."
He looked aside, for a moment, pensively. "It may even be less unusual than it seems, for that matter. The oddity isn't really the design of the phylum, after all, if you consider the incredible range of evolutionary possibilities we can see in the Burgess Shale. Is Bemmie really so outlandish, matched up against Wiwaxia and Opabinia and Anomalocaris—not to mention Hallucigenia? For that matter, it occurred to one of my current graduate students, when we discussed the subject, that your initial impression may actually not be far from the truth. Imagine an offshoot of the cephalopod family which took to land; had some of its tentacles migrate and become shorter for movement, and others evolve for manipulation or catching prey on land. It develops the platelike supports for land propulsion and the skull is the internalization of the shell. Farfetched, perhaps, although . . ."