Mechanisms of kin discrimination inferred from pedigrees and the spatial distribution of mates

Where animals avoid inbreeding, different mechanisms of kin discrimination can leave different “signatures” in the patterns of observed mate relationship. For example, consider a species with no paternal care. If females avoid mating with familiar individuals, one would expect a deficit of offspring whose parents are maternal half-siblings, but paternal half-siblings would be unfamiliar with each other and thus mate at the frequency expected by chance. If spatial cues are used to avoid inbreeding, females would be expected to produce few offspring with males (even unrelated males) living near the female’s birth site. We searched for these and other signatures with data from a long-term study of bannertailed kangaroo rats Dipodomys spectabilis in Arizona, USA, using a combination of intensive censusing, mapping of available dens, microsatellite-based parentage determination, and a randomization routine that determines the numbers of offspring expected if females in the population mate in...

当动物避免近亲繁殖时，不同的亲缘识别（kin discrimination）机制会在观测到的配偶关系模式中留下不同的“印记”。例如，考虑一个无父方抚育的物种：若雌性避免与熟悉个体交配，则父母为母系半同胞的后代数量应出现不足，而父系半同胞彼此不熟悉，因此交配频率符合随机预期；若利用空间线索（spatial cues）避免近亲繁殖，则雌性与（即使是非亲缘的）出生地点附近的雄性交配产生的后代数量应较少。我们利用美国亚利桑那州旗尾更格卢鼠（banner-tailed kangaroo rats，Dipodomys spectabilis）的长期研究数据，通过密集普查、可用洞穴绘图、基于微卫星（microsatellite）的亲权鉴定（parentage determination）以及随机化程序（randomization routine）等方法，寻找这些及其他印记——该随机化程序可确定种群中雌性若以……方式交配时预期的后代数量。