Applied Zoology and Nature Conservation, Zoological Institute and Museum, University of Greifswald, Greifswald, Germany.
Sci Rep. 2024 Nov 20;14(1):28736. doi: 10.1038/s41598-024-80130-w.
Fluctuating asymmetry, the non-directional deviation from bilateral symmetry resulting from developmental instability, can indicate early-life environmental stress. While fluctuating asymmetry can affect individual survival and reproductive success, its effect on fitness differs between species. Here, we analyzed up to 27 years of mark-recapture data from 894 RFID tagged individuals of three forest-living bat species in southern Germany to investigate the degree of fluctuating asymmetry in forearm length. In Bechstein's bats, Myotis bechsteinii, the species with the highest sample size, we furthermore investigated if fluctuating asymmetry has become more frequent over the study period, a time when juvenile bats have grown larger forearms in response to warmer summers. We also investigated whether fluctuating asymmetry affects individual lifespan and lifetime reproductive success in female Myotis bechsteinii. The degree of fluctuating asymmetry clearly exceeding the measurement error estimated on recaptured individuals was similar in all three species (1.8%). In female Myotis bechsteinii, the frequency of fluctuating asymmetry did not increase over the course of the study and even strong asymmetry had no effect on individual reproductive success and life expectancy. Our data suggest that fluctuating asymmetry is a poor predictor of fitness in the female Myotis bechsteinii studied, and is so far unaffected by the warming environment which is leading to larger individuals in our study population.
波动不对称是由发育不稳定导致的非定向偏离双侧对称性，可以指示早期生活环境压力。虽然波动不对称会影响个体的生存和繁殖成功率，但它对不同物种的适应度的影响是不同的。在这里，我们分析了来自德国南部三种森林蝙蝠物种的 894 个 RFID 标记个体长达 27 年的标记-重捕数据，以研究前臂长度的波动不对称程度。在样本量最大的巴氏蝠（Myotis bechsteinii）中，我们进一步研究了波动不对称是否在研究期间变得更加频繁，这是一个青少年蝙蝠的前臂因温暖的夏季而变得更大的时期。我们还研究了波动不对称是否会影响雌性巴氏蝠的个体寿命和终生繁殖成功率。在所有三种物种中，波动不对称的程度明显超过了在重新捕获的个体上估计的测量误差（1.8%）。在雌性巴氏蝠中，波动不对称的频率在研究过程中没有增加，即使是强烈的不对称也不会影响个体的繁殖成功率和预期寿命。我们的数据表明，波动不对称是研究中雌性巴氏蝠适应度的一个较差预测指标，而且到目前为止，它不受导致我们研究种群中个体变大的温暖环境的影响。
