Life History Cost/Benefit Trade-offs in Cynomys gunnisoni

甘尼森草原土拨鼠（Cynomys gunnisoni）以前是美国西部生态系统的重要组成部分，是金雕、游隼、土狼、山猫、獾和黑足雪貂的常见猎物。在20世纪70年代早期，射杀和中毒使这些动物濒临灭绝。人们对它们的繁殖和种群生物学知之甚少。这项拟议中的研究将研究生活在亚利桑那州石化森林国家公园自然条件下的甘尼森草原土拨鼠的自然历史和种群生物学。近亲繁殖通常产生劣等后代。像其他动物一样，甘尼森草原土拨鼠避免与父母、后代和兄弟姐妹等亲属进行极端的近亲交配。他们是否也会避免与远房亲戚交配？通过直接观察已知家谱个体的交配，甘尼森草原土拨鼠之间适度近亲繁殖的频率，以及这种近亲繁殖是否会产生劣等后代，将被确定。集体哺育，即哺育另一个雌性的后代，在自然条件下生活的哺乳动物中是罕见的。试图理解明显的利他主义案例，如公共护理，对进化和行为生态学家构成了最大的挑战之一。甘尼森草原土拨鼠之间的集体护理发生在三种不同的环境中，影响了超过10%的青少年。还将调查这种高频率公共护理的直接和最终原因。

Gunnison's prairie dogs (Cynomys gunnisoni) formerly were an important part of the ecosystem of the western United States, serving as common prey for golden eagles, peregrine falcons, coyotes, bobcats, badgers, and black-footed ferrets. Shooting and poisoning brought these animals to the brink of extinction in the early 1970's. Little is known about their reproductive and population biology. The proposed research will examine the natural history and population biology of Gunnison's prairie dogs living under natural conditions at Petrified Forest National Park in Arizona. Inbreeding usually produces inferior offspring. Like other animals, Gunnison's prairie dogs avoid extreme inbreeding with relatives such as parents, offspring, and siblings. Do they also avoid mating with more distant kin such as first and second cousins? By directly observing copulations of individuals of known genealogies, the frequency of moderate inbreeding among Gunnison's prairie dogs and whether such inbreeding yields inferior offspring will be identified. Communal nursing, the suckling of another female's offspring, is rare among mammals living under natural conditions. Trying to understand apparent cases of altruism such as communal nursing poses one of the greatest challenges to evolutionary and behavioral ecologists. Communal nursing among Gunnison's prairie dogs occurs in three different contexts, and affects more than 10% of all juveniles. The proximate and ultimate causes for this high frequency of communal nursing will also be investigated.