These two datasets report the information at the populational ("Population_Biogeography2017-2018.csv") and individual ("Telomere_Zootocavivipara_2015-2017.csv") levels. At populational level, we studied the covariation of multiple biogeographic measures to obtain an integrative index of population extinction risk. At individual level, we examined what factors best explained the variation in lizard telomere length. We also uploaded the R code ("DataAnalysis_Telomerelizards_AndreazDupoue.R") used to analyse these data, in which we detailed all variables.