The relationships between reptile species richness and a state’s proportion of protected land A latitude B latitude range C and number of physiographic regions D between the proportion of a state’s reptile species that are country endemics and the state’s human population density E latitude range F and elevation range G between the proportion of a state’s reptile species that are in an IUCN category of concern and a state’s human population density H and between the proportion of a state’s reptile species that are listed in SEMARNAT (2019) and a state’s human population density for Mexico I.