干旱区生态环境知识资源中心

[ A southern pied babbler (Turdoides bicolor) subordinate female immediately before dispersal to become dominant in a new group. Dispersal is an important mechanism whereby southern pied babblers avoid inbreeding; though there is no sex-bias in dispersal distance, individuals move twice as far from birth groups as from subsequent groups. Southern pied babblers are found throughout the Kalahari Desert. A habituated population is intensively studied at the Pied Babbler Research Project, Kuruman River Reserve, Northern Cape, South Africa. Image courtesy Tom Flower. ] Nelson-Flower, M.J., Hockey, A.R., O’Ryan, C.O. & Ridley, A.R. (2012) Inbreeding avoidance mechanisms: dispersal dynamics in cooperatively breeding southern pied babblers. Journal of Animal Ecology, 81, 875882. Cooperatively breeding species, in which some individuals help others to rear their offspring, face a high risk of inbreeding because of close relatedness within social groups. Many species circumvent this problem via sex-biased dispersal, in which one sex is more likely to disperse (and to disperse further), while the other stays and helps. In the absence of sex-biased dispersal, more complex dispersal patterns can arise, based on kin recognition. However, this can also present challenges when dispersal distances are short, leading to clusters of relatives on neighbouring territories. In this issue, break important new ground by unravelling adaptive incest-avoidance mechanisms in a cooperatively breeding bird without sex-biased dispersal. They provide an elegant demonstration of finely tuned dispersal distances together with cognitively based methods for knowing whom to avoid as mates.