PT  - JOURNAL ARTICLE
AU  - Salomé H. Clemente
AU  - Inês Santos
AU  - Rita Ponce
AU  - Leonor R. Rodrigues
AU  - Susana A. M. Varela
AU  - Sara Magalhães
TI  - Despite reproductive interference, the net outcome of reproductive interactions among spider mite species is not necessarily costly
AID  - 10.1101/113274
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 113274
4099  - http://biorxiv.org/content/early/2017/03/03/113274.short
4100  - http://biorxiv.org/content/early/2017/03/03/113274.full
AB  - Reproductive interference is considered a strong ecological force, potentially leading to species exclusion. This supposes that the net effect of reproductive interactions is strongly negative for one of the species involved. Testing this requires a comprehensive analysis of interspecific reproductive interactions, accounting for the order and timing of mating events, and for their effects on either fertility or fecundity. To this aim, we measured reproductive interactions between a focal species, Tetranychus urticae, and an invasive (T.evansi) and a resident (T. ludeni) species, varying the mating sequence and interval, and measuring the effect of such crosses on fecundity and offspring sex ratio (a measure of fertility, as these species are haplodiploid). We found that mating with heterospecifics affected fecundity and sex ratio negatively, but also positively, depending on the species involved, and on the order and timing of mating events. To assess the net effect of these interactions on T. urticae, we performed a meta-analysis on the data obtained. This revealed that the net effect of the interaction T. urticae – T. evansi was neutral, whereas that between T. urticae and T. ludeni was slightly positive for T. urticae. Therefore, the net effect of such interactions may be weak despite strong effects of particular events. In natural situations the outcome of reproductive interactions will thus hinge upon the frequency of each event.