Laboratory of Insect Evolutionary Biology and Ecology, Faculty of Biology, University of Bialystok, Ciołkowskiego 1J, 15-245, Białystok, Poland.
MTA-ELTE-MTM Ecology Research Group, Pázmány Péter s. 1/C., Budapest, 1117, Hungary.
Sci Rep. 2020 Jun 25;10(1):10394. doi: 10.1038/s41598-020-66922-w.
Adult survival and longevity in insects are key life-history traits, but their variation between sexes and individuals in natural populations is largely unexplored. Sexual divergence in senescence, the decline in survival with age is also poorly understood. Based on an intensive mark-recapture dataset of the butterfly Polyommatus daphnis, we aimed to assess whether adult survival is age-dependent, and to estimate life span distribution and abundance of males and females using Cormack-Jolly-Seber and Jolly-Seber models. Female survival slightly increased with date of emergence and slightly decreased with age, while male survival considerably declined with age. Mean life span of females (12.7 days) was ~50% higher than that of males (8.5 days), but two times higher if only the oldest 5% of each sex was considered (39 vs.19 days). Abundance of females (358 ± 14) and males (359 ± 11) was similar, but peak abundance of males preceded that of females by 11 days. Our results suggest that senescence is much more rapid in males than in females in this butterfly, which is in agreement with sexual selection theory. We also conclude that estimating life span distributions provides much more valuable information on the demography of natural populations than simply reporting the mean life span.
昆虫的成年存活率和寿命是关键的生活史特征，但它们在自然种群中雌雄个体之间的变化很大程度上尚未被探索。衰老的性分化，即随年龄增长而生存能力下降的现象也知之甚少。基于对蝴蝶 Polyommatus daphnis 的密集标记-重捕数据集，我们旨在评估成年存活率是否随年龄而变化，并使用 Cormack-Jolly-Seber 和 Jolly-Seber 模型估计雌雄个体的寿命分布和丰度。雌性的存活率随出茧日期略有增加，随年龄略有下降，而雄性的存活率随年龄显著下降。雌性的平均寿命（12.7 天）比雄性（8.5 天）高出约 50%，但如果只考虑每个性别中最老的 5%，则高出两倍（39 天对 19 天）。雌性（358±14）和雄性（359±11）的丰度相似，但雄性的丰度峰值比雌性早 11 天。我们的研究结果表明，在这种蝴蝶中，雄性的衰老速度比雌性快得多，这与性选择理论一致。我们还得出结论，估计寿命分布比简单报告平均寿命能提供更有价值的关于自然种群动态的信息。
