Some have claimed that for humans the coalescence to one (or first coalescent) does not happen for well over a million years back in time, calling into question the idea of a single-couple human origin.
One of the claims Dennis Venema makes in his book is that the effective population size of our last common ancestor with chimps has never been fewer than 10,000.
Darwinists point to similarities across species, classes, and phyla, and argue that this shows we’re all descended from a common ancestor.
If one insists on and is committed to naturalism, then naturalistic, evolutionary, explanations are what you will find.
The idea here is that, in different species, the same damaging mutation can be found in the same pseudogenes.