Lack of subspecies-recognition in breeding Barn Swallows (Hirundo rustica transitiva)

Assortative social interactions based on (sub)species recognition can be a driving force in speciation processes. To determine whether breeding Barn Swallows Hirundo rustica transitiva in Israel behave differentially towards members of their own subspecies, relative to a different, transient subspecies H. r. rustica and two sympatrically breeding species (Sand Martin Riparia riparia and House Sparrow Passer domesticus), we conducted a territory intrusion experiment near active nests using taxidermy models. Females responded less to the models than males, and the patterns of the recorded behavioral response traits co-varied statistically with sub- or species identity of the models, but none showed patterns of response selectivity for con(sub)specific model types only. These results do not support a role for subspecies recognition in the territorial intrusion responses of H. r. transitiva.

Automated summary

In an experiment conducted in Israel, it was found that Barn Swallows reacted differently to models based on their species or subspecies identity, but did not show selective responses towards models of the same (sub)species. Female Barn Swallows responded less to the models compared to males.