Aggressiveness and submissiveness in spotted hyaenas: one trait or two?

Aggressive and submissive behaviours are commonly assumed to represent two extremes of a single personality trait, often labelled ‘aggressiveness’. However, most studies focus exclusively on behaviour elicited by conspecific aggression, rates at which aggressive expressed, without considering either unprovoked behaviour, or the intensity actions themselves. Utilizing long-term data set spanning 27 years dyadic agonistic interactions among spotted hyaenas, Crocuta crocuta , including counts intensities all acts we assessed consistency within individuals in these behaviours. We found that both aggression submission performed adult female hyaenas varied with context, neither measure was consistent over time were strongly affected social rank, suggesting rate measures traits. Although rank influenced acts, did not vary rank. Intensities also but individual females regardless age, may no significant correlation between lifetime averages supporting hypothesis different traits rather than opposite ends spectrum. Lifetime uncorrelated fitness, analysis average suggests reproductive success be lower spectrum behavioural its centre after controlling for action stabilizing selection. • Hyaenas showed Aggressive/submissive correlated individuals. Individual fitness loosely such acts. Rank significantly frequency expressed. showing very high low had offspring survival.