Ecological and evolutionary consequences of alternative sex-change pathways in fish.
Sci Rep 2017;
7:9084. [PMID:
28831108 PMCID:
PMC5567342 DOI:
10.1038/s41598-017-09298-8]
[Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 07/25/2017] [Indexed: 11/09/2022] Open
Abstract
Sequentially hermaphroditic fish change sex from male to female (protandry) or vice versa (protogyny), increasing their fitness by becoming highly fecund females or large dominant males, respectively. These life-history strategies present different social organizations and reproductive modes, from near-random mating in protandry, to aggregate- and harem-spawning in protogyny. Using a combination of theoretical and molecular approaches, we compared variance in reproductive success (Vk*) and effective population sizes (Ne) in several species of sex-changing fish. We observed that, regardless of the direction of sex change, individuals conform to the same overall strategy, producing more offspring and exhibiting greater Vk* in the second sex. However, protogynous species show greater Vk*, especially pronounced in haremic species, resulting in an overall reduction of Ne compared to protandrous species. Collectively and independently, our results demonstrate that the direction of sex change is a pivotal variable in predicting demographic changes and resilience in sex-changing fish, many of which sustain highly valued and vulnerable fisheries worldwide.
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