Variation in thermal biology of three closely related lizard species across an elevation gradient

The critical thermal limits of organisms and the thermal sensitivity of their performance tends to vary predictably across latitudinal gradients. There has been comparatively less investigation into variation in thermal limits biology with altitude, despite similar gradients in environmental temperatures with elevation. To redress this, we examined species critical thermal limits (CTmin and CTmax); thermal sensitivity of locomotor performance, and shelter site attributes, in three lizard species that replace one another along a contiguous elevation gradient in south eastern Australia. The species examined consisted of a highland specialist, Liopholis guthega, mid elevation species L. montana, and lowland L. whitii. We found similar habitat attributes between the species, but L. guthega predominantly occurred in open habitat which may reflect a strategy for maximising exposure to insolation. We found intraspecific variation in lizard thermal traits, most notably in cold tolerance of L. g...生物的临界热极限及其运动表现的热敏感性，通常会随纬度梯度呈现可预测的变化规律。尽管环境温度随海拔高度同样存在类似的梯度变化，但针对海拔梯度下生物热极限变异的研究仍相对较少。为填补这一研究空白，我们针对澳大利亚东南部沿连续海拔梯度依次替代分布的3种蜥蜴，测定了其物种临界热极限（CTmin和CTmax）、运动表现的热敏感性以及隐蔽位点特征。本次研究涉及的3个物种分别为高地特有种古氏石石龙子（Liopholis guthega）、中海拔物种蒙塔石龙子（L. montana）以及低海拔物种惠特石龙子（L. whitii）。研究发现，这3种蜥蜴的生境特征整体相似，但古氏石石龙子主要栖息于开阔生境，这可能是其最大化接受日照辐射的适应策略。我们还发现蜥蜴热性状存在种内变异，其中尤以古氏石石龙子的耐寒能力最为显著……