Distant Drumming: morphological correlates of habitat and courtship behaviour in the Ruffed Grouse (Bonasa umbellus)
Krilow, Justin M.
Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience
The Ruffed Grouse (Bonasa umbellus) is a resident game bird of North America. Unlike other birds, male Ruffed Grouse do not vocalize during courtship, and are dependent upon ‘drumming’, a ‘wingbeat’ display, for the acoustic component of their courtship behaviour. Because this wingbeat display is unique, I investigated morphological correlates that could underlie its production. First, I examined wing shape among grouse from museum specimens using various morphometrics. I found that wing morphology corresponds with habitat, behaviour and phylogentic relationships within Tetraoninae. Next, I examined the brains of male and female Ruffed Grouse. I detected seasonal plasticity between males collected during the breeding and non-breeding seasons; those collected during the breeding season had larger motor regions than those collected during the non-breeding season. My findings indicate that habitat and wing shape are correlated among grouse, and that seasonal changes in brain morphology contribute to the production of the drumming display.
Avian brain, , courtship behaviour , geometric morphometrics , Ruffed Grouse , seasonal plasticity , wing shape