Empirical test on the relative climatic sensitivity between individuals of narrowly and broadly distributed species

摘要: Climate change is already influencing global ecology, exacerbating human-induced biodiversity loss with potentially devastating results. A first step to addressing climate impacts on conservation better understand how and what extent species will be affected. Species smaller geographic distributions are commonly perceived at highest risk of extinction. However, estimates vulnerability frequently based simplifying assumptions regarding climatic tolerance, usually arrived through the use models that associate mean spatial or temporal values distributions. Model estimated tolerances may improved by incorporating either finer resolutions and/or additional distribution-limiting factors like dispersal, habitat connectivity, interactions. underlying assumption species-level reflect individual can skew toward over-or underestimation. We empirically derived fitness reaction norms biomass seed pod count estimate relative sensitivity individuals broadly distributed (BD) narrowly (ND) across temperature water gradients. Temperature treatments were local station data IPCC projections change. On basis norms, we infer examine ND relatively more vulnerable than BD species. Study included Mimulus guttatus Clarkia purpurea nudatus gracilis ssp. tracyi. Compared M. nudatus (ND), M. guttatus exhibited responses significantly sensitive temperature. Conversely, compared C. purpurea (BD), C. gracilis tracyi In addition, measured unexpected positive from both increases in Our results support idea that, when examined a scale, size species' distribution does not necessarily correlate vulnerability.