BEYOND THE PARADIGMS OF COSPECIATION AND HOST-SWITCH: IS SYMPATRIC SPECIATION AN IMPORTANT MODE OF SPECIATION FOR PARASITES?

The great majority of studies oil host-parasite associations, either theoretical or empirical, have focused on cospeciation and host-switch minimizing the importance of sympatric speciation,a mode of speciation that can be also defined as intra-host speciation. Sympatric speciation is considered when it single host species is infested by a monophyletic parasite lineage. The parasite speciates Without a corresponding host cospeciation event and this leads to two or more lineages of parasites oil single host species. A recent Study illustrates how the diversification of Dactylogyrus spp. parasitizing cyprinid fish meets the four conditions required to recognize a case of sympatric speciation, according to Coyne (2007). However, inferring mode of speciation does not help to depict the mechanism of sympatric/intra-host speciation and theoretical model of speciation can be useful to investigate the conditions of sympatric speciation in parasites, as it has been already done for free-living organisms. Finally we aim at highlighting that diversification of parasites through intra-host speciation is maybe a prevalent mode of speciation in parasites, as the numerous number of parasite species flocks suggest, and that parasites,ire also good models for investigating the mechanisms of sympatric speciation.