Niche width predicts extinction from climate change and vulnerability of tropical species

Climate change may be a major threat to global biodiversity, especially to tropical species. Yet, why tropical species are more vulnerable to climate change remains unclear. Tropical species are thought to have narrower physiological tolerances to temperature, and they have already experienced a higher estimated frequency of climate-related local extinctions. These two patterns suggest that tropical species are more vulnerable to climate change because they have narrower thermal niche widths. However, no studies have tested whether species with narrower climatic niche widths for temperature have experienced more local extinctions, and if these narrower niche widths can explain the higher frequency of tropical local extinctions. Here, we test these ideas using resurvey data from 538 plant and animal species from 10 studies. We found that mean niche widths among species and the extent of climate change (increase in maximum annual temperatures) together explained most variation (>75%) i...

气候变化或已成为全球生物多样性面临的主要威胁之一，对热带物种的影响尤为显著。然而，热带物种为何对气候变化更为脆弱敏感，其内在机制迄今尚未明确。现有研究认为，热带物种对温度的生理耐受范围更窄，且据估算其发生气候相关局地灭绝的频率也更高。上述两类现象表明，热带物种对气候变化的脆弱性或源于其更狭窄的热生态位宽度（thermal niche widths）。但目前尚无研究验证：温度气候生态位更狭窄的物种是否经历了更高的局地灭绝率，以及这类更窄的生态位宽度能否解释热带地区更高的局地灭绝发生频率。本研究依托来自10项研究的538个动植物类群的重调查数据，对上述假说进行验证。研究结果显示，物种的平均生态位宽度与气候变化程度（年最高气温的升高幅度）二者共同解释了超过75%的变异……