One of the top scientific journals in the world, Nature, has published what would seem to be a ground-breaking paper. The paper claims to have found evidence for the independent evolution of nervous system similarities across the Bilateria. As the abstract explains:
Our findings … suggest that the similarities in dorsoventral patterning and trunk neuroanatomies evolved independently in Bilateria.
By the end of the manuscript the authors are even more confident:
Therefore, the expression of dorsoventral transcription factors evolved independently from the trunk neuroanatomy at least in certain bilaterian lineages
This is a monumental claim, but there is only one problem: It is blatantly false. The paper’s findings did not “suggest” the evolution, independent or otherwise, of the transcription factor expression patterns. They certainly did not demonstrate, show, or find such an incredible conclusion.
It would be difficult to overstate how misleading this paper is. It provides literally zero evidence for any such evolution. Nothing. Nada.
There simply is no such scientific evidence in the paper. The claim that they found that the expression of dorsoventral transcription factors evolved independently in certain bilaterian lineages is not even wrong.
Let’s be clear about this. I am not saying their claim is weak. I am not saying their claim is faulty. I am not saying they failed to make their case conclusively. The problem is they don’t have any case at all.
We cannot criticize the science because, well, there is no science. For a paper entitled “Convergent evolution of bilaterian nerve cords,” one would have expected at least some evidence and explanation for the evolution of bilaterian nerve cords.
Unfortunately papers such as this inform journalists and science writers. They report that scientists have now discovered yet another aspect of evolution. It is yet another example of how science proves evolution.
In fact, if one is looking for a meaningful takeaway, what the study did find is that the expectations of evolution — that nervous system similarities would align with the evolutionary tree — turned out to be, like so many other of evolution’s predictions — false. But that doesn’t fit the narrative.
Image source: Field Museum, Chicago, via Wikicommons.
Cross-posted at Darwin’s God.