Funding for this research was provided by:
National Natural Science Foundation of China (31572216)
Text and Data Mining valid from 2019-09-10
Received: 13 December 2018
Accepted: 4 September 2019
First Online: 10 September 2019
Ethics approval and consent to participate
: Tree sparrows were sampled and processed with the permission of Committee on the Ethics of Animal Experiments of School of Life Sciences, Lanzhou University, China.
: Not applicable.
: The authors declare that they have no competing interests.