Lichter James B, Lambert Connor T, Solomon Nancy G, Keane Brian
Department of Biology, Miami University, Oxford, OH, USA.
Department of Psychology, University of Alberta, Edmonton, AB, Canada.
J Mammal. 2020 Jun 16;101(4):990-999. doi: 10.1093/jmammal/gyaa058. eCollection 2020 Aug 31.
Individuals of either sex may display alternative behaviors to obtain copulations, but few studies have examined the breeding patterns of females and males in populations where individuals of both sexes exhibit alternative reproductive tactics (ARTs). In prairie voles (), most adults are territorial, residing at a single nest site either as male-female pairs or as solitary individuals. However, some adults adopt nonterritorial, wandering tactics. During two field seasons monitoring prairie vole populations maintained in seminatural enclosures, we found evidence that females exhibiting different ARTs bred differentially with resident and wandering males. Females residing at a nest with a male bred significantly more often with a paired resident male, primarily their social partner, and significantly less often with male wanderers compared to single resident females or wandering females. These patterns were not due to chance, because paired resident females produced offspring with paired resident males significantly more than expected based on the relative abundance of these males in the population, whereas single resident females produced offspring with male wanderers significantly more than expected based on the proportion of male wanderers in the population. We did not find any evidence that multiple paternity was greater in the litters of single resident females and wanderer females even though these females lacked a male social partner to limit mating access by multiple males. This suggests that mate guarding by a female's male social partner was not the primary determinant of multiple paternity in the litters of females exhibiting different reproductive tactics. However, male ART did affect the likelihood of multiple paternity. Females that produced offspring with single resident or wanderer males had an increased likelihood of multiple paternity relative to females producing offspring with paired resident males. The results of this study show that female and male ARTs can affect breeding patterns.
无论雄性还是雌性个体都可能表现出不同的行为来获得交配机会，但很少有研究考察过在两性个体都表现出替代生殖策略（ARTs）的种群中，雌性和雄性的繁殖模式。在草原田鼠中，大多数成年个体具有领地意识，以雌雄配对或独居的方式居住在单个巢穴中。然而，一些成年个体采取非领地性的、四处游荡的策略。在两个野外季节对半自然围栏中饲养的草原田鼠种群进行监测时，我们发现有证据表明，表现出不同ARTs的雌性与定居雄性和游荡雄性的繁殖情况不同。与单个定居雌性或游荡雌性相比，与雄性一起居住在巢穴中的雌性与配对的定居雄性（主要是其社会伴侣）繁殖的频率要高得多，而与雄性游荡者繁殖的频率则要低得多。这些模式并非偶然，因为配对的定居雌性与配对的定居雄性产生后代的频率明显高于根据这些雄性在种群中的相对丰度所预期的频率，而单个定居雌性与雄性游荡者产生后代的频率则明显高于根据种群中雄性游荡者的比例所预期的频率。我们没有发现任何证据表明，即使这些雌性缺乏雄性社会伴侣来限制多个雄性的交配机会，单个定居雌性和游荡雌性的窝仔中多重父权的情况更普遍。这表明，雌性的雄性社会伴侣进行配偶守卫并不是表现出不同生殖策略的雌性窝仔中多重父权的主要决定因素。然而，雄性ART确实影响了多重父权的可能性。与与配对的定居雄性产生后代的雌性相比，与单个定居或游荡雄性产生后代的雌性出现多重父权的可能性增加。这项研究的结果表明，雌性和雄性ARTs会影响繁殖模式。
