Reticulate evolution

Reticulate evolution, also network evolution, describes the origination of a lineage through the partial merging of two ancestor lineages, leading to relationships better described by a phylogenetic network than a bifurcating tree.
Crossing of distinct lineages can happen through recombination, horizontal gene transfer, or hybrid speciation, and a lineage of such origin thus has two most recent common ancestors. Reticulate evolution can involve species, but also genes, chromosomes, or genomes.