Climate change has already caused local extinction in many plants and animals, based on surveys spanning many decades. As climate change accelerates, the pace of these extinctions may also accelerate, potentially leading to large‐scale, species‐level extinctions. We tested this hypothesis in a montane lizard. We resurveyed 18 mountain ranges in 2021–2022 after only ~7 years. We found rates of local extinction among the fastest ever recorded, which have tripled in the past ~7 years relative to the preceding ~42 years. Further, climate change generated local extinction in ~7 years similar to that seen in other organisms over ~70 years. Yet, contrary to expectations, populations at two of the hottest sites survived. We found that genomic data helped predict which populations survived and which went extinct. Overall, we show the increasing risk to biodiversity posed by accelerating climate change and the opportunity to study its effects over surprisingly brief timescales.
Around the world, many species are confined to “Sky Islands,” with different populations in isolated patches of montane habitat. How does this pattern arise? One scenario is that montane species were widespread in lowlands when climates were cooler, and were isolated by local extinction caused by warming conditions. This scenario implies that many montane species may be highly susceptible to anthropogenic warming. Here, we test this scenario in a montane lizard (
- Award ID(s):
- NSF-PAR ID:
- Publisher / Repository:
- Date Published:
- Journal Name:
- Molecular Ecology
- Page Range / eLocation ID:
- p. 2610-2624
- Medium: X
- Sponsoring Org:
- National Science Foundation
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