Of coarse no-one knows with great accuracy, but there are methods to sort out likelihoods.
snip
...
Scientists have been able to make these discoveries by revisiting a concept proposed almost a century ago — fitness (or adaptive) landscapes — with modern technologies. They can use fitness landscapes to quantify the relationship between changes to the viral genome and its ability to replicate and infect a new host. The topographic maps representing that relationship can help to reconstruct the virus’s history, and they could also at least potentially predict its future.
...
Comments