Well, this is timely for our discussion
Scientists say evolution may work differently than we thought
Zhang and his colleagues set out to examine a key assumption behind that theory. Are beneficial mutations really that scarce?
Their results suggest the answer may be no.
Helpful Mutations May Be Surprisingly Common
Using large deep mutational scanning datasets from their own lab and others, the team looked at the effects of many mutations in model organisms such as yeast and E. coli. In deep mutational scanning, scientists create many mutations in a gene or region of the genome and then measure how those changes affect the organism.
The researchers tracked organisms over many generations and compared them with the wild type, or the version most commonly found in nature. By measuring growth, they could estimate whether a mutation helped, hurt, or had little effect.
They found that more than 1% of the amino acid changing mutations they examined were beneficial.
I do not have access to the original paper…
14 November 2025 - Adaptive tracking with antagonistic pleiotropy results in seemingly neutral molecular evolution
Note that this study does not include multicellular models, but it does serve to reinforce that model parameters must be consistent with the continuation of life as found in nature, and that environment plays a role.