Note that duplication-loss events and transfer followed by the loss of the transferred gene, unlike a transfer followed by the loss of the non-transferred gene and speciation-loss events, leave no trace and are therefore undetectable.
The contributions of horizontal gene transfer (HGT) to bacterial evolution and speciation are currently unclear and estimates range from minimal to very relevant [2], [4].
Horizontal transfer, a major source of evolution and speciation in bacteria (Lawrence 2002), can be one of the mechanisms for the origin of TEs due to their mobility and capacity to integrate into the host DNA (Roulin et al. 2008).
7. Lawrence JG: Selfish operons and speciation by gene transfer.
In the context of gene family evolution, the two trees are the gene tree and the species tree, and in the well-studied Duplication-Transfer-Loss model (DTL), the events are speciation, duplication, transfer and loss.
In the typical formulation of this problem, the goal is to reconcile an input gene tree (gene family phylogeny) to the corresponding rooted species tree by postulating speciation, duplication, transfer and loss events.
In our DTLI model, divergence in a gene tree arises through one of four events: duplication, transfer, speciation and deep coalescence.
Gene-species tree reconciliations are evaluated under a parsimony framework20 where a cost is assigned to each of the four possible events describing gene family evolution (i.e. speciation, duplication, horizontal transfer, and loss).
For better understanding of reticulate evolution, several reticulate evolutionary models have been proposed and actively studied to address various reticulate processes, such as hybrid speciation, lateral gene transfer and recombination.
These findings suggested that MPK10 were existed in older species and are lost during divergence and speciation, after which it was only able to be transferred to members of the brassicaceae family.
