Biological and extrinsic correlates of extinction risk in Chinese lizards.

Abstract

China is a country with one of the most species-rich reptile faunas in the world. However, nearly a quarter of Chinese lizard species assessed by the China Biodiversity Red List are threatened. Nevertheless, to date, no study has explicitly examined the pattern and processes of extinction and threat in Chinese lizards. In this study, we conducted the first comparative phylogenetic analysis of extinction risk in Chinese lizards. We addressed the following 3 questions: (1) What is the pattern of extinction and threat in Chinese lizards? (2) Which species traits and extrinsic factors are related to their extinction risk? (3) How can we protect Chinese lizards based on our results? We collected data on 10 species traits (body size [BS], clutch size, geographic range size, activity time, reproductive mode, habitat specialization [HS], habitat use, leg development, maximum elevation, and elevation range) and 7 extrinsic factors (mean annual precipitation (MAP), mean annual temperature, mean annual solar insolation, normalized difference vegetation index (NDVI), human footprint, human population density, and human exploitation). After phylogenetic correction, these variables were used separately and in combination to assess their associations with extinction risk. We found that Chinese lizards with a small geographic range, large BS, high HS, and living in high MAP areas were vulnerable to extinction. Conservation priority should thus be given to species with the above extinction-prone traits so as to effectively protect Chinese lizards. Preventing future habitat destruction should also be a primary focus of management efforts because species with small range size and high HS are particularly vulnerable to habitat loss.