Sinsch Ulrich, Dehling Jonas Maximilian
Department of Biology, Zoology Group, University of Koblenz-Landau, Koblenz, Germany.
PLoS One. 2017 Feb 9;12(2):e0171666. doi: 10.1371/journal.pone.0171666. eCollection 2017.
Age- and size-related life-history traits of anuran amphibians are thought to vary systematically with latitude and altitude. Because the available data base is strongly biased towards temperate-zone species, we provide new estimates on eight afrotropical Reed Frog species. A meta-analysis of the demographic traits in 44 tropical anuran species aims to test for the predicted clinal variation and to contrast results with variation detected in temperate-zone species. The small-sized reed frogs reach sexual maturity during the first or second year of life, but longevity does not exceed three to four years. Latitudinal effects on demographic life-history traits are not detectable in tropical anurans, and altitudinal effects are limited to a slight size reduction at higher elevations. Common features of anuran life-history in the tropics are early sexual maturation at small size and low longevity resulting in low lifetime fecundity. This pattern contrasts with that found in temperate-zone anurans which mature later at larger size and grow considerably older yielding greater lifetime fecundity than in the tropics. Latitudinal and altitudinal contraction of the yearly activity period shape the evolution of life-history traits in the temperate region, while trait variation in the tropics seems to be driven by distinct, not yet identified selective forces.
人们认为，无尾两栖动物与年龄和体型相关的生活史特征会随着纬度和海拔的变化而系统地改变。由于现有数据库严重偏向于温带物种，我们给出了对8种非洲芦苇蛙的新估计。对44种热带无尾两栖动物的人口统计学特征进行的荟萃分析旨在检验预测的渐变变异，并将结果与温带物种中检测到的变异进行对比。体型较小的芦苇蛙在出生后的第一或第二年达到性成熟，但寿命不超过三到四年。在热带无尾两栖动物中，纬度对人口统计学生活史特征的影响无法检测到，海拔的影响仅限于海拔较高处体型略有减小。热带地区无尾两栖动物生活史的共同特征是体型小、性成熟早和寿命短，导致终生繁殖力低。这种模式与温带无尾两栖动物不同，温带无尾两栖动物体型较大时成熟较晚，寿命长得多，终生繁殖力比热带地区的无尾两栖动物更高。一年活动期的纬度和海拔收缩塑造了温带地区生活史特征的演变，而热带地区的特征变异似乎是由尚未确定的独特选择力驱动的。
