Collaborative proposal: Evaluating phenotypic plasticity's role in adaptive evolution

合作提案：评估表型可塑性在适应性进化中的作用

• 批准号: 1753865
• 负责人: David Pfennig
• 金额: $ 56.69万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-06-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1753865&HistoricalAwards=false
• 关键词: Collaborative; proposal; Evaluating; phenotypic; plasticity

Many organisms can respond to changes in their environment by dramatically altering their morphology, behavior, or physiology, and the widespread occurrence of this ability has provoked a spirited debate. On the one hand, many biologists maintain that the flexibility to change appearance, behavior or physiology are of no relevance to evolution, because evolution requires genetic change. On the other hand, a growing number of researchers have suggested that such flexibility plays a critical role in evolution by jump-starting genetic change. This research will help resolve this controversy by investigating whether changes in appearance, behavior and/or physiology precede (and enable) the evolutionary origins of major, new, genetically-encoded features. The research will specifically evaluate whether pre-existing, diet-induced flexibility has contributed to the evolution of a novel, complex body form in spadefoot frogs. Thus, not only will this research provide important insights into the evolutionary process, it will also shed new light onto one of biology's enduring mysteries: how complex features originate. The research will also promote educational outreach by training school children and undergraduate students and by organizing public talks at museums.This research will test the Plasticity-First hypothesis of adaptive evolution. To do so, the proposed research will focus on spadefoot toads. Like most frogs, tadpoles in the genus Scaphiopus develop only into a typical 'omnivore' morph. By contrast, tadpoles in the genus Spea exhibit striking plasticity: depending on their diet, they develop into either omnivores or a novel 'carnivore' morph. Interestingly, certain components of this distinctive carnivore morph can be diet-induced in Scaphiopus. Moreover, some Spea populations have secondarily lost the omnivore-carnivore plasticity and become monomorphic. Indeed, in some populations, selection has favored the near fixation of the carnivore morph. Thus, as a group, spadefoots appear to represent different stages in the evolution of the novel carnivore morph: from its possible initial induction (in Scaphiopus), to its refinement as part of a novel developmental 'switch' (in many Spea populations), to its ultimate fixation (in some Spea populations). The planned research will evaluate whether this novel carnivore phenotype arose through plasticity-first evolution by contrasting development, genetic variation, and performance in different species/populations that serve as different evolutionary stages in the origins of this distinctive form. In doing so, the research will evaluate the critical predictions of the plasticity-first hypothesis. This research will thereby help to clarify plasticity's role in evolutionary innovation and provide a roadmap for others to test the plasticity-first hypothesis.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

许多生物可以通过显著改变形态、行为或生理来应对环境的变化，这种能力的广泛存在引发了激烈的争论。一方面，许多生物学家坚持认为，改变外表、行为或生理的灵活性与进化无关，因为进化需要基因改变。另一方面，越来越多的研究人员提出，这种灵活性通过启动基因变化在进化中起着关键作用。这项研究将通过调查外观、行为和/或生理上的变化是否先于（并使之成为）主要的、新的、遗传编码特征的进化起源，来帮助解决这一争议。这项研究将特别评估先前存在的、由饮食引起的柔韧性是否对一种新的、复杂的身体形态的进化做出了贡献。因此，这项研究不仅为进化过程提供了重要的见解，而且还将为生物学的一个长期谜团——复杂特征是如何起源——提供新的线索。这项研究还将通过培训在校儿童和大学生以及在博物馆组织公开讲座来促进教育推广。本研究将检验适应性进化的可塑性优先假说。为了做到这一点，拟议的研究将集中在锹足蟾蜍身上。像大多数青蛙一样，Scaphiopus属的蝌蚪只发育成典型的“杂食”形态。相比之下，Spea属的蝌蚪表现出惊人的可塑性：根据它们的饮食，它们要么变成杂食动物，要么变成一种新的“食肉动物”形态。有趣的是，这种独特的食肉动物形态的某些成分可能是由饮食诱导的。此外，一些种群已次级丧失了杂食性-食肉性的可塑性，成为单态种群。事实上，在某些种群中，自然选择倾向于食肉动物形态的近乎固定。因此，作为一个群体，大脚似乎代表了新型食肉动物形态进化的不同阶段：从可能的初始诱导（在棘足目中），到作为新型发育“开关”的一部分的改进（在许多种种群中），再到最终的固定（在一些种种群中）。计划中的研究将通过对比不同物种/种群的发育、遗传变异和表现来评估这种新型食肉动物表型是否通过可塑性优先进化产生，这些物种/种群是这种独特形式起源的不同进化阶段。在此过程中，该研究将评估可塑性优先假设的关键预测。因此，这项研究将有助于阐明可塑性在进化创新中的作用，并为其他人测试可塑性优先假设提供路线图。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

How stabilizing selection and nongenetic inheritance combine to shape the evolution of phenotypic plasticity

稳定选择和非基因遗传如何结合起来塑造表型可塑性的进化

• DOI: 10.1111/jeb.13475
• 发表时间: 2019
• 期刊: Journal of Evolutionary Biology Research
• 作者: Levis, N. A. Pfennig

Evolution: Ancestral Plasticity Promoted Extreme Temperature Adaptation in Thermophilic Bacteria

进化：祖先的可塑性促进了嗜热细菌的极端温度适应

• DOI: 10.1016/j.cub.2019.11.080
• 发表时间: 2020
• 期刊: Current Biology
• 影响因子: 9.2
• 作者: Levis, Nicholas A.;Pfennig, David W.
• 通讯作者: Pfennig, David W.

Evolution and the flexible organism

进化与灵活的有机体

• 发表时间: 2022
• 期刊: American scientist
• 作者: Pfennig, D.W.

Dead Spadefoot Tadpoles Adaptively Modify Development in Future Generations: A Novel Form of Nongenetic Inheritance?

死去的锹足蝌蚪适应性地改变了后代的发育：一种新的非基因遗传形式？

• DOI: 10.1643/ce-19-286
• 发表时间: 2020
• 期刊: Copeia
• 影响因子: 2.6
• 作者: Pfennig, Katrina S.;Pfennig, David W.
• 通讯作者: Pfennig, David W.

Disentangling the developmental origins of a novel phenotype: enhancement versus reversal of environmentally induced gene expression

解开新表型的发育起源：环境诱导的基因表达的增强与逆转

• DOI: 10.1098/rspb.2022.1764
• 发表时间: 2022
• 期刊: Proceedings of the Royal Society B: Biological Sciences
• 作者: Levis, Nicholas A.;McKay, Daniel J.;Pfennig, David W.
• 通讯作者: Pfennig, David W.