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Among vertebrates, amphibians have particular characteristics (e.g., permeable skin) that make them extremely dependent on abiotic factors such as temperature and humidity (Duellman & Trueb, 1994).Amphibians are the most endangered group of vertebrates in the world (Alroy, 2015;Ceballos et al., 2017;Stuart et al., 2004). Recent studies estimate that approximately 200 amphibian species (2.4% of all global diversity) are already extinct, and direct and indirect factors related to human activities threaten 41% (Alroy, 2015;Hoffmann et al., 2010; IUCN, 2020). Even those classified as Least Concern (LC) by the IUCN (International Union for Conservation of Nature-an

Realistic predictions about the impacts of climate change onbiodiversity requires gathering ecophysiological data and the critical thermal maxima (CTMax) is the most frequently used index to assess the thermal vulnerability of species. In the present study, we performed a systematic review to understand how acclimation and altitude affect CTMax estimates for amphibian and non-avian reptile species. We retrieved CTMax data for anurans, salamanders, lizards, snakes, and turtles/terrapins. Data allowed to perform a multilevel random effects meta-analysis to answer how acclimation temperature affect CTMax of Anura, Caudata, and Squamata and also meta-regressions to assess the influence of altitude on CTMax of frogs and lizards. Acclimation temperature influenced CTMax estimates of tadpoles, adult anurans, salamanders, and lizards, but not of froglets. In general, the increase in acclimation temperature led to higher CTMax values. Altitudinal bioclimatic gradient had an inverse effect for estimating the CTMax of lizards and anuran amphibians. For lizards, CTMax was positively influenced by the mean temperature of the wettest quarter. For anurans, the relationship is inverse; we recover a trend of decreasing CTMax when max temperature of warmest month and precipitation seasonality increase. There is an urgent need for studies to investigate the thermal tolerance of subsampled groups or even for which we do not have any information such as Gymnophiona, Serpentes, Amphisbaena, and Testudines. Broader phylogenetic coverage is mandatory for more accurate analyses of macroecological and evolutionary patterns for thermal tolerance indices as CTMax.

The regions between the tropics provide climatic characteristics that contribute to the formation of unique vegetation typologies, the Tropical Forests. It is estimated that these forests are home to about 50 000 tree species. The Atlantic Forest, located mostly on the Brazilian coast is an example of the richness of phanerophytes inside an important hotspot for biodiversity. Understanding the relationship between these edaphoclimatic factors and the richness of tree species in the Atlantic Forest is important to establish conservation strategies in this threatened biome. Our main objective was to analyse the relationship between abiotic variables and tree species richness in the southern region of the state of Bahia, Brazil. In this sense, we used data from tree species and abiotic factors (extracted from the WorldClim and FAO platforms) in a selection of mixed generalized linear multimodels. Variables related to temperature and precipitation in the driest periods influenced the richness of tree species in the study region. Whereas temperature seasonality and minimum temperature of the coldest month influenced negatively the values for extrapolated richness the maximum temperature of the hottest month exhibited a positive influence for richness indexes. These results emphasize that the maintenance of the arboreal richness in tropical zones is directly dependent of the climatic seasonality. In the present study, we point out the importance of climatic factors for the maintenance of tree species in a region that has expressive numbers of tree species per hectare, one of the world records in this index.

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