Twiss Sean D, Poland Veronica F, Graves Jefferson A, Pomeroy Paddy P
School of Biological and Biomedical Sciences, Durham University, South Road, Durham DH1 3LE, UK.
Mol Ecol. 2006 Jun;15(7):1939-53. doi: 10.1111/j.1365-294X.2006.02927.x.
Molecular studies of pinniped breeding systems exhibit a broad range of agreement and disagreement with observational indices of male breeding success. Grey seal studies have reported considerable discrepancies between genetic and behavioural paternity measures that have been interpreted as evidence of previously unidentified male strategies and/or tactics. Therefore, these studies have the power to fundamentally alter our perceptions of mating systems. However, other pinniped studies exhibit no such disagreements, and one possible explanation for disparities may be sampling biases in space and time. Therefore, it is essential that potential sampling biases are examined to evaluate the likelihood of previously unidentified male strategies. We examined paternities assigned at the North Rona grey seal colony between 1999 and 2002 in relation to concurrent detailed behavioural and locational data for males and females. We found that (i) for females observed in sexual interaction(s) during their oestrus period, it was highly probable that one of the interacting males fathered their next pup; (ii) over 80% of assigned paternities agreed with observations of the in-colony behaviour and spatio-temporal proximity of the males and females involved; and (iii) a minority of females exhibit mate choice and seek sires outside their local male's home range, although evidence suggests that these females mate on the colony rather than at sea. In conclusion, nearly all paternities assigned agreed with expectation based upon detailed knowledge of the spatio-temporal patterns of individuals during the breeding season. We found little evidence of unidentified male strategies at North Rona, Scotland, whereas further examination of mechanisms of female choice may be productive.
鳍足类动物繁殖系统的分子研究与雄性繁殖成功的观察指标之间存在广泛的一致和分歧。灰海豹研究报告了遗传和行为亲子关系测量之间存在相当大的差异，这些差异被解释为先前未被识别的雄性策略和/或战术的证据。因此，这些研究有能力从根本上改变我们对交配系统的看法。然而，其他鳍足类动物研究并未表现出此类分歧，差异的一个可能解释可能是空间和时间上的抽样偏差。因此，检查潜在的抽样偏差以评估先前未被识别的雄性策略的可能性至关重要。我们研究了1999年至2002年在北罗纳灰海豹繁殖地确定的亲子关系，并将其与雄性和雌性同时期的详细行为和位置数据相关联。我们发现：（i）对于在发情期观察到有性行为的雌性来说，与之互动的雄性之一极有可能是其下一只幼崽的父亲；（ii）超过80%的确定亲子关系与所涉及的雄性和雌性在繁殖地内的行为以及时空接近度的观察结果一致；（iii）少数雌性表现出配偶选择，并在当地雄性的活动范围之外寻找配偶，尽管有证据表明这些雌性是在繁殖地而不是在海上交配。总之，几乎所有确定的亲子关系都与基于繁殖季节个体时空模式的详细知识所预期的情况相符。我们在苏格兰北罗纳几乎没有发现未被识别的雄性策略的证据，而进一步研究雌性选择机制可能会有成果。
