To those of you that follow science blogs, or even - heaven forbid - read academic journals, this will be (relatively) old news, the paper in question having been published at the end of last month. For for the benefit of my other reader, however, I thought it was worth re-hashing here. Donald Williamson is a retired prof from the University of Liverpool who has some decidedly... um... eccentric views about evolution. Specifically, he believes that caterpillars and butterflies were once two separate organisms: a worm-like ancestral caterpillar and a flying insect ancestor. These then hybridized to produce a single lineage with two life stages. He also proposes that velvet worms (Phylum Onychophora) are the most likely candidate for the wormy ancestor.
OK, let's stop for a moment and review. Onychophora and Insects. Two separate PHYLA. This is not like making a mule or a liger. Short of my mating with a rhododendron and producing a weird man-shrub creature, that's about as extreme as it can get. Now as you all know, there are many people in the world who hold, to put it mildly, odd views on life. The internet is a mine of weird and wonderful stuff that would previously have struggled to find an outlet. But this paper did not appear on a obscure website devoted to extreme hybridisation. No. It appeared in the Proceedings of the National Academy of Sciences, which is (or perhaps - in the light of recent events - was) one of the world's finest academic journals.
How did this happen? Well, for those of you of a non-scientific bent, we scientists have a system called peer review, which means that before your paper can get published in a reputable journal a bunch of other scientists in your field get to scrutinize the manuscript for flaws, or to make sure that you are not stark raving mad. But PNAS is also the house journal of the American National Academy of Sciences. Election to membership of the Academy is one of the highest honors that can be bestowed on a scientist and is a recognition of the member's prodigious intellect. So as far as PNAS is concerned, if one of their members thinks the paper is OK, then why bother putting it through review by lesser mortals.
In this case, the paper was communicated to PNAS by Lynn Margulis, a professor at UMASS Amherst. Margulis is enormously respected, having come up with her own extremely wacky evolutionary hypothesis that cellular organelles (the small, membrane bound structures inside eukaryotic cells that perform many of the cell's physiological functions) actually originated as small, free-living bacteria that were ingested by proto-Eukaryotes in the extremely distant past. Amazingly, Margulis proved to be right and rewrote our understanding of the early evolution of life on Earth.
So is Williamson also right? The answer (sadly for Onychophoran fans) seems to be "no," or at least not on the basis of this paper. Basically, rather than providing proof that he's right, he's challenged his detractors to prove that he's wrong. This wasn't good enough for the seven academic journals that he approached with this paper prior to having Margulis take it to PNAS. But as far as PNAS was concerned, as long as an Academy member thought it was OK, then OK it was.
Apparently the National Academy of Sciences will be dropping this method of manuscript submission next year. For now, you can enjoy Williamson's paper here.