What mechanisms can create a mismatch between the history of genes and the history of species?

Question

Quizplus · Accepted Answer

Introgression and incomplete lineage sorting are mechanisms that can create discrepancies between gene histories and species histories. Introgression involves the transfer of genetic information between species through hybridization and backcrossing, while incomplete lineage sorting occurs when ancestral genetic polymorphisms are not uniformly sorted among the descendants, leading to gene trees that do not match the species tree. Genetic hitchhiking, however, is a process where alleles change in frequency not due to their own effects on fitness but because they are linked to other alleles that are under selection. It does not inherently cause a mismatch between the history of genes and the history of species in the context of the question.

What Mechanisms Can Create a Mismatch Between the History of Genes