Editor´s Choice - Parent-environmental interactions shape acoustic signatures in tree swallows: a cross-fostering experiment
Submitted by avianbiology on 11 March 2014.
It has previously been found that the acoustic signature of begging calls is similar between nestlings from the same brood. Even though this similarity seems adaptive in colonial species where nestlings might mix, it might also be important for parental recognition of their offspring after fledgling in passerines where young are still dependent on being fed by their parents for some time. This similarity might come about either by genetic and maternal effects or by environmental effects shared by the brood mates. In a recent, elegant paper in J. Avian Biol., Reers and colleagues, set out to test these two models of the origin in similarity in begging calls in a population of tree swallows. They found that when nestlings grew up together with unrelated nestlings (moved there as part of the experimental set-up), all nestlings converged somewhat to the same acoustic signature and thus that the similarity was primarily the result of a shared environment. However, an additional effect of genetic/maternal origin could not be excluded. The fact that similarity due to a common environment was most important makes sense for a species, like the tree swallow, with a very high proportion of extra-pair young in each brood. Thus, there is selection on the young to converge in their begging calls to secure feedings by their social parents also after fledging.
Jan-Åke Nilsson, Editor-in-Chief
Read the paper for free on Wiley online library:
http://onlinelibrary.wiley.com/doi/10.1111/j.1600-048X.2013.00201.x/abst...
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