1 research outputs found
Persistence of single species of symbionts across multiple closelyrelated host species
Some symbiont species are highly host-specific, inhabiting only one or a very few host species, and
typically have limited dispersal abilities. When they do occur on multiple host species, populations of
such symbionts are expected to become genetically structured across these different host species,
and this may eventually lead to new symbiont species over evolutionary timescales. However, a low
number of dispersal events of symbionts between host species across time might be enough to prevent
population structure and species divergence. Overall, processes of evolutionary divergence and the
species status of most putative multi-host symbiont systems are yet to be investigated. Here, we used
DNA metabarcoding data of 6,023 feather mites (a total of 2,225 OTU representative sequences) from
147 infracommunities (i.e., the assemblage consisting of all mites of different species collected from
the same bird host individual) to investigate patterns of population genetic structure and species status
of three different putative multi-host feather mite species Proctophyllodes macedo Vitzthum, 1922,
Proctophyllodes motacillae Gaud, 1953, and Trouessartia jedliczkai (Zimmerman, 1894), each of which
inhabits a variable number of different closely related wagtail host species (genus Motacilla). We show
that mite populations from different host species represent a single species. This pattern was found in
all the mite species, suggesting that each of these species is a multi-host species in which dispersal of
mites among host species prevents species divergence. Also, we found evidence of limited evolutionary
divergence manifested by a low but significant level of population genetic structure among symbiont
populations inhabiting different host species. Our study agrees with previous studies showing a higher
than expected colonization opportunities in host-specific symbionts. Indeed, our results support
that these dispersal events would allow the persistence of multi-host species even in symbionts with
limited dispersal capabilities, though additional factors such as the geographical structure of some bird
populations may also play a role.This work was supported by the MINECO CGL2011-24466 to RJ and
CGL2015-69650-P to RJ and DS