Phenotypic plasticity as a mechanism of cave colonization and adaptation

eLife

Guanliang Meng¹  Romana Gračan²  Mireille Steck³  Megan L Porter³  Mandy Ng⁴  Breanna Hollifield⁴  William Jeffery⁴  Helena Bilandžija⁵  Kenneth J Renner⁶  Andrew D Koch⁶  Helena Ćetković⁷ 

[1] BGI-Shenzhen, Shenzhen, China;China National GeneBank, BGI-Shenzhen, Shenzhen, China;Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia;Department of Biology, University of Hawai’i at Mānoa, Honolulu, United States;Department of Biology, University of Maryland, College Park, United States;Department of Biology, University of Maryland, College Park, United States;Department of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia;Department of Biology, University of South Dakota, Vermillion, United States;Department of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia;

关键词: Astyanax mexicanus;    cavefish;    colonization;    rapid evolution;    cave adaptation;    total darkness;    Other;   

DOI  :  10.7554/eLife.51830

来源: publisher

【 摘 要 】

A widely accepted model for the evolution of cave animals posits colonization by surface ancestors followed by the acquisition of adaptations over many generations. However, the speed of cave adaptation in some species suggests mechanisms operating over shorter timescales. To address these mechanisms, we used Astyanax mexicanus, a teleost with ancestral surface morphs (surface fish, SF) and derived cave morphs (cavefish, CF). We exposed SF to completely dark conditions and identified numerous altered traits at both the gene expression and phenotypic levels. Remarkably, most of these alterations mimicked CF phenotypes. Our results indicate that many cave-related traits can appear within a single generation by phenotypic plasticity. In the next generation, plasticity can be further refined. The initial plastic responses are random in adaptive outcome but may determine the subsequent course of evolution. Our study suggests that phenotypic plasticity contributes to the rapid evolution of cave-related traits in A. mexicanus.

【 授权许可】

CC BY