Poster presentation 12th International Mammalogical Congress

The role of the climatic niche in the imbalanced diversification of two sister groups (#603)

Xue Lv 1 , Lin Xia 2 , Deyan Ge 2 , Zhixin Wen 2 , Qisen Yang 2
  1. Yunnan University, Kunming, Yunnan, China
  2. Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China

Imbalanced diversification between closely related taxa is commonly observed, but the mechanisms remain poorly understood. We quantified the temperature and precipitation niche positions and niche breadths for 114 representative species of two closely related subfamilies of Arvicolinae and Cricetinae, and assessed the relationships among climatic niche positions, niche breadths and diversification rates. The results showed that cricetine rodents were restricted to drier environments and had narrower niche breadths than arvicoline rodents. The relationship between precipitation niche positions and niche breadths was much stronger in cricetine rodents than in arvicoline rodents. In addition, the results showed a significant positive relationship between clade level precipitation niche breadths and net diversification rates. The overlap of both niches of cricetine rodents overlapped significantly stronger than of arvicoline rodents, suggesting that aridity has acted as a filter on cricetine rodents to form a non-significant phylogenetic relationship among this clade along the precipitation gradient. Our results suggest that arid environments have strongly shaped the global speciation pattern of arid-adapted taxa by constraining those with small precipitation niche breadths. This mechanism may explain the prevalence of exclusively arid-adapted taxa and the low species richness of cricetine rodents.