A study examines how anthropogenic and climate stressors correlate with local mammalian extinction. Although human activity and global warming are thought to be responsible for the rapid extinction of mammalian species, long-term data on the links is sparse. Zhibin Zhang and colleagues analyzed more than 9,000 historical records dating from 905 BCE to 2006 CE of the distribution of 11 mammalian species found in China and examined how the mammals' population sizes were associated with climate-change-related stress, represented by air temperature, and anthropogenic stress, represented by cropland coverage and human population density. Both extreme climate change and intensified human disturbances were associated with increased local extinction. Since 1644 CE, all species' survival rates decreased by 36-100%, whereas cropland coverage, human population density, and average summer temperatures rapidly increased. Global cooling prior to 1911 CE and global warming since 1911 CE were both positively associated with increased local extinction. Compared with small and medium-sized mammals, large mammals, such as elephants, pandas, and rhinos, had earlier and larger population declines. The findings suggest that both global cooling and global warming may reduce habitat sizes caused by range shift, leading to the local extinction of mammalian populations. Moreover, habitat fragmentation caused by human disturbance may have also accelerated the local extinction of the mammal species by hampering their movements, according to the authors.
Article #18-18019: "Historical records reveal the distinctive associations of human disturbance and extreme climate change with local extinction of mammals ," by Xinru Wan et al.
MEDIA CONTACT: Zhibin Zhang, University of Chinese Academy of Sciences, Beijing, CHINA; tel: 86-10-62556418; email: zhangzb@ioz.ac.cn
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Proceedings of the National Academy of Sciences