Carrie Arnold writes:

In the fall of 2019, the world began one of the largest evolutionary biology experiments in modern history. Somewhere near the city of Wuhan in eastern China, a coronavirus acquired the ability to live inside humans rather than the bats and other mammals that had been its hosts. It adapted further to become efficient at spreading from one person to the next, even before the body’s defenses could rise against it. But the evolutionary chess game didn’t stop there, and we have a Greek alphabet soup of SARS-CoV-2 variants to prove it.

Researchers around the world are trying to understand the virus’s evolution in more detail, and particularly how mutations in SARS-CoV-2 alter its ability to spread among humans. “A well-adapted virus today could be maladaptive tomorrow as the host develops resistance, and then it has to figure out a new way to infect that host. That drives the innovation that drives the novelty,” said Justin Meyer, an evolutionary biologist at the University of California, San Diego.

Grim as the human toll from the constantly shifting pandemic is, the abundance of scientific data from watching the virus evolve as it moves around the globe has been instructive. “COVID has given us some of the most beautiful examples of evolution in action,” said Luca Ferretti, a statistical geneticist at the Big Data Institute of the University of Oxford. [Continue reading…]