Farquharson Katherine A, Hogg Carolyn J, Belov Katherine, Grueber Catherine E
School of Life and Environmental Sciences Faculty of Science The University of Sydney Sydney Australia.
San Diego Zoo Global San Diego USA.
Evol Appl. 2020 May 19;13(9):2179-2189. doi: 10.1111/eva.12981. eCollection 2020 Oct.
Incorporating mate choice into conservation breeding programs can improve reproduction and the retention of natural behaviors. However, different types of genetic-based mate choice can have varied consequences for genetic diversity management. As a result, it is important to examine mechanisms of mate choice in captivity to assess its costs and benefits. Most research in this area has focused on experimental pairing trials; however, this resource-intensive approach is not always feasible in captive settings and can interfere with other management constraints. We used generalized linear mixed models and permutation approaches to investigate overall breeding success in group-housed Tasmanian devils at three nonmutually exclusive mate choice hypotheses: (a) advantage of heterozygous individuals, (b) advantage of dissimilar mates, and (c) optimum genetic distance, using both 1,948 genome-wide SNPs and 12 MHC-linked microsatellites. The managed devil insurance population is the largest such breeding program in Australia and is known to have high variance in reproductive success. We found that nongenetic factors such as age were the best predictors of breeding success in a competitive breeding scenario, with younger females and older males being more successful. We found no evidence of mate choice under the hypotheses tested. Mate choice varies among species and across environments, so we advocate for more studies in realistic captive management contexts as experimental or wild studies may not apply. Conservation managers must weigh up the need to wait for adequate sample sizes to detect mate choice with the risk that genetic changes may occur during this time in captivity. Our study shows that examining and integrating mate choice into the captive management of species housed in realistic, semi-natural group-based contexts may be more difficult than previously considered.
将配偶选择纳入保护繁育计划可以提高繁殖率并保留自然行为。然而，不同类型的基于遗传的配偶选择对遗传多样性管理可能会产生不同的影响。因此，研究圈养环境下的配偶选择机制以评估其成本和效益非常重要。该领域的大多数研究都集中在实验配对试验上；然而，这种资源密集型方法在圈养环境中并不总是可行的，并且可能会干扰其他管理限制因素。我们使用广义线性混合模型和排列方法，利用1948个全基因组单核苷酸多态性（SNP）和12个与主要组织相容性复合体（MHC）相关的微卫星，对塔斯马尼亚袋獾群体饲养中的总体繁殖成功率进行了研究，以检验三个并非相互排斥的配偶选择假设：（a）杂合个体的优势；（b）不同配偶的优势；（c）最佳遗传距离。受管理的袋獾保险种群是澳大利亚最大的此类繁育计划，已知其繁殖成功率存在很大差异。我们发现，在竞争激烈的繁殖场景中，年龄等非遗传因素是繁殖成功的最佳预测指标，年轻雌性和年长雄性的繁殖成功率更高。在所测试的假设下，我们没有发现配偶选择的证据。配偶选择因物种和环境而异，因此我们主张在实际的圈养管理环境中进行更多研究，因为实验研究或野外研究可能并不适用。保护管理人员必须权衡等待足够样本量以检测配偶选择的必要性与圈养期间可能发生遗传变化的风险。我们的研究表明，在实际的、基于半自然群体的环境中，将配偶选择纳入圈养物种的管理可能比之前认为的更加困难。
