Funding for this research was provided by:
National Natural Science Foundation of China (31372209)
The Fundamental Research Funds for the Central Universities (2572017AA20)
Text and Data Mining valid from 2018-12-01
Received: 4 May 2018
Accepted: 12 November 2018
First Online: 4 December 2018
: The research complied with the protocols established by the China Wildlife Conservation Association and the legal requirements of China.
: Not applicable.
: The authors declare that they have no competing interests.
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