The adaptive value of morphological, behavioural and life-history traits in reproductive female wolves

摘要: Reproduction in social organisms is shaped by numerous morphological, behavioural and life-history traits such as body size, cooperative breeding age of reproduction, respectively. Little known, however, about the relative influence these different types on particularly context environmental conditions that determine their adaptive value. Here, we use 14 years data from a long-term study wolves (Canis lupus) Yellowstone National Park, USA, to evaluate effects ecological factors reproductive performance (litter size survival) females. At individual level, litter survival improved with mass declined (c. 4-5 years). Grey-coloured females had more surviving pups than black females, which likely contributed maintenance coat colour polymorphism this system. The effect pack was nonlinear peaked at eight then declined, increased rapidly up three wolves, beyond it gradually. population decreased increasing wolf canine distemper outbreaks. different-level success followed > group population. Body primary determinant size. also main driver survival, disease. Reproductive gains because larger may mitigate losses negative density dependence These findings highlight value large sociality promoting fitness stochastic competitive environments.