Discrimination between lineage-specific shelters by bat- and human-associated bed bugs does not constitute a stable reproductive barrier.
The common bed bug Cimex lectularius, has been recently shown to constitute two host races, which are likely in the course of incipient speciation. The human-associated lineage splits from the ancestral bat-associated species deep in the history of modern humans, likely even prior to the Neolithic Period and establishment of the first permanent human settlements. Hybridization experiments between these two lineages show that post-mating reproductive barriers are incomplete due to local variation. As mating takes place in off-host refugia marked by aggregation semiochemicals, the present investigation tested the hypothesis that bed bugs use these semiochemicals to differentiate between refugia marked by bat- and human-associated bed bugs; this would constitute a pre-copulation isolation mechanism. The preference for lineage-specific odors was tested using artificial shelters conditioned by a group of either male or female bed bugs. Adult males were assayed individually in four-choice assays that included two clean unconditioned control shelters. In most assays, bed bugs preferred to rest in conditioned shelters, with no apparent fidelity to shelters conditioned by their specific lineage. However, 51 % of the bat-associated males preferred unconditioned shelters over female-conditioned shelters of either lineage. Thus, bed bugs show no preferences for lineage-specific shelters, strongly suggesting that semiochemicals associated with shelters alone do not function in reproductive isolation.
Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21, Prague 6, Czech Republic. o.balvin@centrum.cz.
Ondřej
O
Balvín
Department of Botany and Zoology, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic.
Tomáš
T
Bartonička
Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 21, Prague 6, Czech Republic.
Kateřina
K
Pilařová
Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, 27695, USA.
Zachary
Z
DeVries
Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, 27695, USA.
Coby
C
Schal
D000818:Animals; D001511:Bedbugs / Q000145:classification* / Q000235:genetics / Q000502:physiology*; D001681:Biological Assay; D002685:Chiroptera / Q000469:parasitology*; D004478:Ectoparasitic Infestations / Q000469:parasitology* / Q000662:veterinary*; D005260:Female; D006801:Humans; D006824:Hybridization, Genetic; D008297:Male; D009812:Odorants / Q000032:analysis; D012098:Reproduction
Aggregation behavior; Parasites; Pheromones; Pre-copulation reproduction isolation