Convergent evolution may make travel restrictions redundant. The genetic mutations that cause evolution may arise at random. But natural selection often produces creatures that are similar, despite living in different environments. For example birds, bats, pterodactyls and insects all developed wings independently, because they were a nifty way to travel. This process is known as convergent evolution.

Viruses evolve, too. SARS-CoV-2 which causes covid-19, replicates while infecting its host. As it does, the virus’s genetic information—a sequence of 30,000 rna letters—is sometimes corrupted. These mutations can make SARS-CoV-2 more dangerous in several ways. They can increase transmissibility, evade detection by tests, avoid immune responses (including from vaccines) and cause more severe illness...

The Economist: The same covid-19 mutations are appearing in different places