Mechanisms of diversification in North American frogs

北美青蛙的多样化机制

• 批准号: 238462-2006
• 负责人: Lougheed, Stephen
• 金额: $ 2.26万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2006
• 资助国家: 加拿大
• 起止时间: 2006-01-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=335136
• 关键词: Mechanisms; diversification; North; American; frogs

Despite over six decades of research, a complete understanding of the mechanisms that generate species diversity remains elusive. Recently developed molecular tools and analytical methods afford us excellent opportunities to answer outstanding questions on the process of speciation. We address two of these using field and genetic studies of a small North American frog, the spring peeper. Our previous work identified major evolutionary lineages that have come into secondary contact in the northern portion of the species range after long periods of geographical isolation. For our first project, we will use a range of molecular and experimental approaches to test whether three pairs of divergent lineages now in secondary contact show evidence of reproductive isolation (a hallmark of speciation): reduction of ability to produce viable offspring, and divergence in male advertisement calls and female receptivity to them. Evidence of reproductive isolation will indicate that historical separation of populations may provide opportunity for divergence, but offers no insight as to its cause. Our second project will examine the proximate mechanisms that may cause such divergence. Specifically within an environmentally heterogeneous 4000 sq. km. area in Eastern Ontario, we will test whether selection pressures in habitats differing in vegetation structure and microclimate can produce significant differences in (1) spring emergence and calling by males, and (2) the acoustic properties of male advertisement calls. The combined insights from these projects will significantly advance our knowledge of the importance of, and interplay among, geographical isolation, contact zone dynamics, and ecological selection in diversification and speciation.

尽管经过了60多年的研究，但对产生物种多样性的机制的完整理解仍然难以捉摸。最近开发的分子工具和分析方法为我们提供了很好的机会，以回答悬而未决的问题的过程中的形态。我们解决其中两个使用领域和遗传研究的一个小北美青蛙，春天偷窥。我们以前的工作确定了主要的进化谱系，经过长期的地理隔离，这些谱系在物种范围的北方部分进行了二次接触。对于我们的第一个项目，我们将使用一系列分子和实验方法来测试现在处于二次接触的三对不同谱系是否显示出生殖隔离的证据（物种形成的标志）：产生可行后代的能力降低，以及男性广告呼叫和女性对它们的接受性的分歧。生殖隔离的证据将表明，历史分离的人口可能会提供机会的分歧，但没有提供任何见解，其原因。我们的第二个项目将研究可能导致这种差异的近似机制。特别是在一个环境异质的4000平方米。公里.在东部安大略地区，我们将测试是否选择压力在不同的植被结构和小气候的栖息地可以产生显着差异（1）春季出现和男性呼吁，（2）男性广告呼叫的声学特性。从这些项目的综合见解将显着推进我们的知识的重要性，以及相互作用，地理隔离，接触区动态，多样化和物种形成的生态选择。