Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA, 94305-5020, USA.
Center for Conservation Biology, Stanford University, Stanford, CA, 94305-5020, USA.
Glob Chang Biol. 2015 Nov;21(11):3901-16. doi: 10.1111/gcb.13016. Epub 2015 Sep 22.
Habitat conversion is a major driver of the biodiversity crisis, yet why some species undergo local extinction while others thrive under novel conditions remains unclear. We suggest that focusing on species' niches, rather than traits, may provide the predictive power needed to forecast biodiversity change. We first examine two Neotropical frog congeners with drastically different affinities to deforestation and document how thermal niche explains deforestation tolerance. The more deforestation-tolerant species is associated with warmer macroclimates across Costa Rica, and warmer microclimates within landscapes. Further, in laboratory experiments, the more deforestation-tolerant species has critical thermal limits, and a jumping performance optimum, shifted ~2 °C warmer than those of the more forest-affiliated species, corresponding to the ~3 °C difference in daytime maximum temperature that these species experience between habitats. Crucially, neither species strictly specializes on either habitat - instead habitat use is governed by regional environmental temperature. Both species track temperature along an elevational gradient, and shift their habitat use from cooler forest at lower elevations to warmer deforested pastures upslope. To generalize these conclusions, we expand our analysis to the entire mid-elevational herpetological community of southern Costa Rica. We assess the climatological affinities of 33 amphibian and reptile species, showing that across both taxonomic classes, thermal niche predicts presence in deforested habitat as well as or better than many commonly used traits. These data suggest that warm-adapted species carry a significant survival advantage amidst the synergistic impacts of land-use conversion and climate change.
生境转换是生物多样性危机的主要驱动因素，但为什么有些物种在新的条件下经历局部灭绝，而有些物种却茁壮成长，目前仍不清楚。我们认为，关注物种的生态位，而不是特征，可能为预测生物多样性变化提供所需的预测能力。我们首先研究了两个亲缘关系截然不同的新热带蛙类，以了解它们对森林砍伐的适应能力，并记录热生态位如何解释森林砍伐耐受性。更能耐受森林砍伐的物种与哥斯达黎加各地更温暖的大气候以及景观内更温暖的小气候相关。此外，在实验室实验中，更能耐受森林砍伐的物种具有临界热极限和跳跃性能最佳值，比更倾向于森林的物种高约 2°C，这与这些物种在栖息地之间经历的约 3°C 的日间最高温度差异相对应。至关重要的是，这两个物种都没有严格地专门适应于任何一种生境——相反，生境的利用由区域环境温度决定。这两个物种都沿着海拔梯度跟踪温度，并将其生境利用从较低海拔的较冷森林转移到较高海拔的较温暖的森林砍伐牧场。为了推广这些结论，我们将分析扩展到哥斯达黎加南部整个中海拔爬行动物群落。我们评估了 33 种两栖动物和爬行动物物种的气候亲缘关系，结果表明，在这两个分类类群中，热生态位预测了在森林砍伐生境中的存在，其预测能力与许多常用特征一样好，甚至更好。这些数据表明，在土地利用转换和气候变化的协同影响下，温暖适应物种具有显著的生存优势。
