Genomic effects of population collapse in a critically endangered ironwood tree Ostrya rehderiana. Issue 1 (December 2018)

• Record Type: Journal Article
• Authors: Yang, Yongzhi; Ma, Tao; Wang, Zefu; Lu, Zhiqiang; Li, Ying; Fu, Chengxin; Chen, Xiaoyong; Zhao, Mingshui; Olson, Matthew S.; Liu, Jianquan
• Is Part Of: Nature communications. Volume 9:Issue 1(2018)
• Page Start: 1
• Page End: 9
• Publication Date: 2018-12
• Subjects: Biology -- Periodicals; Physical sciences -- Periodicals; 505
• DOI: 10.1038/s41467-018-07913-4
• Languages: English
• ISSNs: 2041-1723

Abstract

Abstract Increased human activity and climate change are driving numerous tree species to endangered status, and in the worst cases extinction. Here we examine the genomic signatures of the critically endangered ironwood treeOstrya rehderiana and its widespread congenerO. chinensis . Both species have similar demographic histories prior to the Last Glacial Maximum (LGM); however, the effective population size ofO. rehderiana continued to decrease through the last 10, 000 years, whereasO. chinensis recovered to Pre-LGM numbers.O. rehderiana accumulated more deleterious mutations, but purged more severely deleterious recessive variations than inO. chinensis . This purging and the gradually reduced inbreeding depression together may have mitigated extinction and contributed to the possible future survival of the outcrossingO. rehderiana . Our findings provide critical insights into the evolutionary history of population collapse and the potential for future recovery of the endangered trees. Here, Liu et al. compare the genomic signatures of two tree species, one of which had undergone population collapse. The declining species had low genetic diversity, but had more strongly purged severely deleterious recessive variations, likely due to inbreeding and perhaps mitigating extinction risk.