There is just too much evolutionary distance between the coronavirus samples the Wuhan scientists were working with — all of them genetically sequenced and detailed in published work — and the virus that causes COVID-19.

This is what Fauci meant when he told lawmakers this week that it was “molecularly impossible” for the viruses examined by WIV to evolve into SARS-CoV-2: Generally, the overlap between the genomes of the viruses in the lab and that of SARS-CoV-2 was no more than 80%.

In evolutionary terms, that’s a chasm. In their critical review, the international group of virologists note that SARS-CoV-2 and its closest known relatives have an overlap of about 96%. That “equates to decades of evolutionary divergence,” they wrote.

Given that, Fauci said, “there’s no way” the viruses studied at WIV could have evolved into the virus that has caused 4 million deaths around the world.

Would it be possible to bridge that gap with some deft splicing and dicing in a lab? Perhaps, but if so, telltale marks likely would have been left behind. Those have not been seen by scientists who went looking.