| Title | Climatic stability, not average habitat temperature, determines thermal tolerance of subterranean beetles |
| Abstract | The climatic variability hypothesis predicts the evolution of species with wide thermal tolerance ranges in environments with variable temperatures, and the evolution of thermal specialists in thermally stable environments. In caves, the extent of spatial and temporal thermal variability experienced by taxa decreases with their degree of specialization to deep subterranean habitats. We use phylogenetic generalized least squares to model the relationship among thermal tolerance (upper lethal limits), subterranean specialization (estimated using ecomorphological traits), and habitat temperature in 16 beetle species of the tribe Leptodirini (Leiodidae). We found a significant, negative relationship between thermal tolerance and the degree of subterranean specialization. Conversely, habitat temperature had only a marginal effect on lethal limits. In agreement with the climatic variability hypothesis and under a climate change context, we show that the specialization process to live in deep subterranean habitats involves a reduction of upper lethal limits, but not an adjustment to habitat temperature. Thermal variability seems to exert a higher evolutionary pressure than mean habitat temperature to configure the thermal niche of subterranean species. Our results provide novel insights on thermal physiology of species with poor dispersal capabilities and on the evolutionary process of adaptation to subterranean environments. We further emphasize that the pathways determining vulnerability of subterranean species to climate change greatly depend on the degree of specialization to deep subterranean environments. |
| Source | Ecology (Brooklyn, New York, N.Y.) 103 (4), pp. 1–11 |
| Keywords | cave faunaclimate changeclimatic variability hypothesisdeep subterranean environmenthabitat temperatureLeiodidaemountain passes hypothesisthermal tolerance |
| Journal | Ecology (Brooklyn, New York, N.Y.) |
| Editor | Brooklyn Botanical Garden,, Brooklyn, NY, Stati Uniti d'America |
| Year | 2022 |
| Type | Articolo in rivista |
| DOI | 10.1002/ecy.3629 |
| Authors | Colado, Raquel; Pallares, Susana; Fresneda, Javier; Mammola, Stefano; Rizzo, Valeria; Sanchez-Fernandez, David |
| Text | 466061 2022 10.1002/ecy.3629 ISI Web of Science WOS 000766198100001 cave fauna climate change climatic variability hypothesis deep subterranean environment habitat temperature Leiodidae mountain passes hypothesis thermal tolerance Climatic stability, not average habitat temperature, determines thermal tolerance of subterranean beetles Colado, Raquel; Pallares, Susana; Fresneda, Javier; Mammola, Stefano; Rizzo, Valeria; Sanchez Fernandez, David Univ Murcia; CSIC; Museu Ciencies Nat Zool; Univ Helsinki; Natl Res Council Italy CNR; CSIC UPF The climatic variability hypothesis predicts the evolution of species with wide thermal tolerance ranges in environments with variable temperatures, and the evolution of thermal specialists in thermally stable environments. In caves, the extent of spatial and temporal thermal variability experienced by taxa decreases with their degree of specialization to deep subterranean habitats. We use phylogenetic generalized least squares to model the relationship among thermal tolerance upper lethal limits , subterranean specialization estimated using ecomorphological traits , and habitat temperature in 16 beetle species of the tribe Leptodirini Leiodidae . We found a significant, negative relationship between thermal tolerance and the degree of subterranean specialization. Conversely, habitat temperature had only a marginal effect on lethal limits. In agreement with the climatic variability hypothesis and under a climate change context, we show that the specialization process to live in deep subterranean habitats involves a reduction of upper lethal limits, but not an adjustment to habitat temperature. Thermal variability seems to exert a higher evolutionary pressure than mean habitat temperature to configure the thermal niche of subterranean species. Our results provide novel insights on thermal physiology of species with poor dispersal capabilities and on the evolutionary process of adaptation to subterranean environments. We further emphasize that the pathways determining vulnerability of subterranean species to climate change greatly depend on the degree of specialization to deep subterranean environments. 103 Published version Articolo in rivista Brooklyn Botanical Garden, 0012 9658 Ecology Brooklyn, New York, N.Y. Ecology Brooklyn, New York, N.Y. Ecol. Brooklyn, New York, N.Y. Ecology. Brooklyn, New York, N.Y. stefano.mammola MAMMOLA STEFANO |
