The authors offer a selectionist explanation, which is nevertheless uncertain. Note the repeated use of the subjunctive.
They are not, per the National Academy of Sciences, a “particularly convincing example for speciation.”
“Darwin’s mechanism is dominated by ‘Poison-Pill’ mutations: positively-selected, loss-of-function mutation.” It “squanders genetic information for short-term gain.”
Considering several recent papers shows that eliminating evolutionary words and concepts simplifies and improves scientific explanations.
Evolutionists now increasingly believe that major adaptations are driven by neutral mutations.