University News

SYSU researchers deconstructed Darwin’s conundrum of species invasion

Source: School of Life Sciences
Written by: School of Life Sciences
Edited by: Wang Dongmei

For more than 150 years, biologists focused on invasion biology have looked back to the idea of Charles Darwin in The Origin of Species, which now has been termed ‘Darwin’s naturalisation conundrum’. Darwin proposed that exotics distantly related to natives are more likely to be successful, as they complete less with natives (Darwin's naturalisation hypothesis). However, Darwin also proposed that exotic species closely related to natives should be favored, as they adapt to similar environments as the natives (pre-adaptation hypothesis). This conundrum has been tested across numerous taxa and ecosystems, but the opposing hypotheses have been supported in roughly equal proportions.

Recently, Prof. Wen-sheng Shu and his Ph.D candidate Dr. Shao-peng Li (graduated in 2014), from College of Ecology and Evolution, Sun Yat-sen University, and Prof. Marc W Cadotte from University of Toronto laid out a new framework to reconcile the conundrum. By examining invasion dynamics of 480 plots over 40 years in the Piedmont of New Jersey, USA, they found that exotic species more closely related to native species were more likely to enter, establish and dominate the native communities, which provides strong support for pre-adaptation hypothesis. Further, for the first time, they found that native residents more closely related to the successful invaders were more likely to go locally extinct. These results present challenges to recent studies which used the co-occurrence of exotics with their distantly related natives as evidence for Darwin's naturalisation hypothesis, and highlight it is necessary to incorporate native species displacement into Darwin's phylogenetic framework. By deconstructing Darwin’s conundrum into invasion success and impact, this study could help to reconcile the 150-year-old conundrum.

This paper titled “The effects of phylogenetic relatedness on invasion success and impact: deconstructing Darwin's naturalisation conundrum”, has been published on Oct. 6, 2015 in Ecology Letters, a top journal in ecology and environmental sciences. This is the second publication in this journal by the group this year.

Journal Reference:
Shao-peng Li, Marc W. Cadotte, Scott J. Meiners, Zheng-shuang Hua, Hao-yue Shu, Jin-tian Li & Wen-sheng Shu. (2015). The effects of phylogenetic relatedness on invasion success and impact: deconstructing Darwin’s naturalisation conundrum. Ecology Letters. DOI: 10.1111/ele.12522.