Human activities often replace native forests with warmer, modified habitats that represent novel thermal environments for biodiversity. Reducing biodiversity loss hinges upon identifying which species are most sensitive to the environmental conditions that result from habitat modification. Drawing on case studies and a meta-analysis, we examined whether observed and modelled thermal traits, including heat tolerances, variation in body temperatures, and evaporative water loss, explained variation in sensitivity of ectotherms to habitat modification. Low heat tolerances of lizards and amphibians and high evaporative water loss of amphibians were associated with increased sensitivity to habitat modification, often explaining more variation than non-thermal traits. Heat tolerances alone explained 24-66% (mean = 38%) of the variation in species responses, and these trends were largely consistent across geographic locations and spatial scales. As habitat modification alters local microclimates, the thermal biology of species will likely play a key role in the reassembly of terrestrial communities.

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Amphibians and reptiles are sensitive to changes in the thermal environment, which varies considerably in human‐modified landscapes. Although it is known that thermal traits of species influence their distribution in modified landscapes, how herpetofauna respond specifically to shifts in ambient temperature along forest edges remains unclear. This may be because most studies focus on local‐scale metrics of edge exposure, which only account for a single edge or habitat patch. We predicted that accounting for the combined effect of multiple habitat edges in a landscape would best explain herpetofaunal response to thermally mediated edge effects. We (1) surveyed herpetofauna at two lowland, fragmented forest sites in central Colombia, (2) measured the critical thermal maximum (CTmax) of the species sampled, (3) measured their edge exposure at both local and landscape scales, and (4) created a thermal profile of the landscape itself. We found that species with low CTmax occurred both further from forest edges and in areas of denser vegetation, but were unaffected by the landscape‐scale configuration of habitat edges. Variation in the thermal landscape was driven primarily by changes in vegetation density. Our results suggest that amphibians and reptiles with low CTmax are limited by both canopy gaps and proximity to edge, making them especially vulnerable to human modification of tropical forest. Abstract in Spanish is available with online material.

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Coral snakes of the genus Micrurus have been recorded as prey of rapacious birds, some mammals and other snakes, but so far not as prey of fishes. The black spotted piranha, Pygocentrus cariba, is an opportunistic predator that feeds mainly on fishes, occasionally on other vertebrates, but has so far not been reported to prey on snakes. Herein, based on morphological and molecular data (mitochondrial 16S fragment), we report the first case of predation of P. cariba on the coral snake Micrurus filiformis. Additionally, we briefly discuss the significance of this new finding for the diet of P. cariba and comment on the systematics and distribution of M. filiformis.