New paper out: Complex spatiotemporal variation in processes shaping song variation

I am proud to announce the fourth paper out from my dissertation.  This one is now out as online early in Behaviour.  This paper covers variation in titmouse song between the younger and older hybrid zones based on song recordings and vegetation measurements I took in both Texas and Oklahoma.  To quote from the abstract:

In the recent zone, noise and vegetation structure were correlated with several song characteristics, but in the older zone, these features did not correlate despite similar gradients in song features. Our data, combined with previous studies, suggest that despite overall similarities in characteristics, songs in the older zone may be more shaped by sexual selection, whereas songs in the young zone are shaped by environment. Thus, even within the same species, processes shaping signal structure can vary spatially and temporally.