Nematode endoparasites do not codiversify with their stick insect hosts.

Details

Ressource 1Download: BIB_938B08C65601.P001.pdf (1607.28 [Ko])
State: Public
Version: Final published version
Serval ID
serval:BIB_938B08C65601
Type
Article: article from journal or magazin.
Collection
Publications
Title
Nematode endoparasites do not codiversify with their stick insect hosts.
Journal
Ecology and Evolution
Author(s)
Larose C., Schwander T.
ISSN
2045-7758 (Electronic)
ISSN-L
2045-7758
Publication state
Published
Issued date
2016
Peer-reviewed
Oui
Volume
6
Number
15
Pages
5446-5458
Language
english
Abstract
Host-parasite coevolution stems from reciprocal selection on host resistance and parasite infectivity, and can generate some of the strongest selective pressures known in nature. It is widely seen as a major driver of diversification, the most extreme case being parallel speciation in hosts and their associated parasites. Here, we report on endoparasitic nematodes, most likely members of the mermithid family, infecting different Timema stick insect species throughout California. The nematodes develop in the hemolymph of their insect host and kill it upon emergence, completely impeding host reproduction. Given the direct exposure of the endoparasites to the host's immune system in the hemolymph, and the consequences of infection on host fitness, we predicted that divergence among hosts may drive parallel divergence in the endoparasites. Our phylogenetic analyses suggested the presence of two differentiated endoparasite lineages. However, independently of whether the two lineages were considered separately or jointly, we found a complete lack of codivergence between the endoparasitic nematodes and their hosts in spite of extensive genetic variation among hosts and among parasites. Instead, there was strong isolation by distance among the endoparasitic nematodes, indicating that geography plays a more important role than host-related adaptations in driving parasite diversification in this system. The accumulating evidence for lack of codiversification between parasites and their hosts at macroevolutionary scales contrasts with the overwhelming evidence for coevolution within populations, and calls for studies linking micro- versus macroevolutionary dynamics in host-parasite interactions.
Keywords
Codiversification, cophylogeny, endoparasite, host-parasite interaction
Pubmed
Web of science
Open Access
Yes
Create date
03/06/2016 9:57
Last modification date
20/08/2019 14:56
Usage data