Phenotypic determinants of individual fitness in female fur seals: larger is better
Phenotypic determinants of individual fitness in female fur seals: larger is better
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DOI：
10.1098/rspb.2007.0454
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发表时间：
2007-08-07
影响因子：
4.7
通讯作者：
Guinet, Christophe
中科院分区：
文献类型：
--
作者：
Beauplet, Gwenael;Guinet, Christophe
雌性脊椎动物个体间的适应性差异通常与表型差异有关，这表明体型较大的个体表现出更强的适应性。然而，使用随时间变化的质量指数（例如体重/状况）可能并不代表较长时间间隔内最可靠的指数。很少有研究评估体型 (BS) 对个人健康的直接影响。我们利用对单独标记的雌性亚南极海豹的长期监测数据来解决这一知识差距。较高质量的雌性（即较高的终生繁殖成功率）的 BS 比其同类更大，这与它们为幼崽提供更多和更规律的能量供应的能力相关，可能是通过最大化觅食性能和身体脂肪储存。因此，我们发现我们的研究人群可以根据母性质量分为三个对比类别，其中 33% 的女性生产了超过 71% 的构成下一代的可存活后代。我们认为，对于中心地点采集者来说，较大的 BS 代表着至关重要的选择优势，特别是在利用远程可用资源时。
Inter-individual differences in fitness in female vertebrates have often been related to phenotypic discrepancies, suggesting that bigger individuals exhibit greater fitness. However, the use of the temporally variable indices of quality, such as body mass/condition, may not represent the most reliable index over longer time intervals. Few studies have assessed the direct influence of body size ( BS) on individual fitness. We addressed this knowledge gap using data from long-term monitoring of individually marked female subantarctic fur seals. The females of higher quality ( i.e. higher lifetime reproductive success) were larger in BS than their counterparts, which correlated with their ability to provision their pup with greater and more regular energy supply, possibly through the maximization of foraging performance and body fat storage. We accordingly found that our study population could be divided into three contrasted categories of maternal quality, with 33% of the females producing over 71% of the viable offspring constituting the next generation. We suggest that a larger BS represents a crucial selective advantage for a central place forager, especially when exploiting remotely available resources.