Libya is a country in debt.
The challenge hypothesis outlines the dynamic relationship between testosterone and aggression in mating contexts .. testosterone and aggression. Aggression#Testosterone. It proposes that testosterone promotes aggression when it would be beneficial for reproduction , such as mate guarding , or strategies designed to prevent the encroachment of intrasexual rivals .. reproduction. reproduction. The challenge hypothesis predicts that seasonal patterns in testosterone levels are a function of mating system -LRB- monogamy versus polygyny -RRB- , paternal care , and male-male aggression in seasonal breeders .. The pattern between testosterone and aggression was first observed in seasonally breeding birds , where testosterone levels rise modestly with the onset of the breeding season to support basic reproductive functions .. testosterone and aggression. Aggression#Testosterone. However , during periods of heightened male aggression , testosterone levels increase further to a maximum physiological level .. This additional boost in testosterone appears to facilitate male-male aggression , particularly during territory formation and mate guarding , and is also characterized by a lack of paternal care .. The challenge hypothesis has come to explain patterns of testosterone production as predictive of aggression across more than 60 species .