地山雀（Parushumilis）是青藏高原的特有鸟种，属山雀科鸟类。由于其形态特征与地鸦相近，曾长期被认为是鸦科鸟类，并被命名为“褐背拟地鸦”。
中科院动物研究所动物进化与系统学院重点实验室雷富民研究员领导的鸟类学研究组与诺禾致源合作，对地山雀开展全基因组denovo测序，同时对另外两种山雀（大山雀和黄颊山雀）以及黑尾地鸦进行了重测序比较分析。研究结果从基因组水平进一步确证了地山雀是“山雀”而非“鸦”的分类地位，并初步揭示了该物种适应青藏高原极端环境的遗传印迹。
结果显示，地山雀与黄颊山雀、大山雀的亲缘关系很近，估算分化时间在7.7-9.9个百万年之间。通过与原鸡、火鸡和斑胸草雀的基因组数据比较，发现地山雀基因组中与能量代谢相关的基因家族发生了扩张，而与免疫和嗅觉相关的基因家族发生了收缩；通过对7190个直系同源基因的比对，发现与低氧反应和骨骼发育相关的基因经历了正向选择以及不同程度的快速进化。上述结果进一步揭示了地山雀为适应青藏高原的特殊环境，产生了基本的生存适应策略演化，以及由山雀向鸦的形态特征转变。
该成果于7月1日在线发表于Nature Communications杂志上。（生物谷 Bioon.com）
生物谷推荐的英文摘要
Nature Communications doi:10.1038/ncomms3071
Ground tit genome reveals avian adaptation to living at high altitudes in the Tibetan plateau
Yanhua Qu, Hongwei Zhao, Naijian Han, Guangyu Zhou, Gang Song, Bin Gao, Shilin Tian, Jinbo Zhang, Ruiying Zhang, Xuehong Meng, Yuan Zhang, Yong Zhang, Xiaojia Zhu, Wenjuan Wang, David Lambert, Per G. P. Ericson, Sankar Subramanian, Carol Yeung, Hongmei Zhu, Zhi Jiang, Ruiqiang Li & Fumin Lei
The ground tit (Parus humilis) is endemic to the Tibetan plateau. It is a member of family Paridae but it was long thought to be related to the ground jays because of their morphological similarities. Here we present the ground tit’s genome and re-sequence two tits and one ground jay, to clarify this controversially taxonomic status and uncover its genetic adaptations to the Tibetan plateau. Our results show that ground tit groups with two tits and it diverges from them between 7.7 and 9.9 Mya. Compared with other avian genomes, ground tit shows expansion in genes linked to energy metabolism and contractions in genes involved in immune and olfactory perception. We also found positively selected and rapidly evolving genes in hypoxia response and skeletal development. These results indicated that ground tit evolves basic strategies and ‘tit-to-jay’ change for coping with the life in an extreme environment.
