The Evolution of Placentas in the Fish Family Poeciliidae: an empirical study of macroevolution

鱼类胎盘的进化：宏观进化的实证研究

• 批准号: 1754669
• 负责人: David Reznick
• 金额: $ 97.6万
• 依托单位: University of California-Riverside
• 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: 2018-05-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1754669&HistoricalAwards=false
• 关键词: Evolution; Placentas; Fish; Family; Poeciliidae

How and why do new species evolve? How and why do complex organs, like eyes, evolve? These phenomena happen on time scales much longer than our lives, making it difficult for us to understand how they happened. Species are defined by being distinct from and not breeding with each other. Not interbreeding could be a simple matter of when, where or who you choose to mate with. It could also be caused by a failure to produce offspring that can survive and reproduce. Species today are often kept separate from one another by multiple mechanisms, so we do not know how they evolved in the first place. Likewise, complex organs are like machines with many parts that must all be present and well integrated if the machine is to work, but how did this complexity arise? In each case, nature most often presents us with end products without any clues about how they came about; however, sometimes nature provides groups of species that retain enough clues to these processes for one to be able to study how they occur, as in the case of this research program. One impact of this work pertains to the complex organ that is studied. These investigators are studying the evolution of placentas and are doing so in a context in which they can compare species with placentas with close relatives who lack placentas or have less complex placentas. This diversity enables them to address the consequences of having a placenta, including how it affects fertility. The research will enhance the training of students at multiple levels (high school, college, and post-graduate) as well as provide outreach to the public.The proposed research combines work done at two levels of resolution. First, the investigators will work on all species in the fish family Poeciliidae, enabling them to define the timing and order of evolutionary changes. Second, they will perform experiments on individual species within the family to characterize the mechanisms that cause evolution. They will sequence whole genomes then use the DNA sequences to reconstruct the family tree. They will characterize the biology of every species on the tree, including how females provision their young and how males and females choose who to mate with. These fish all bear live young, but some fully provision eggs before they are fertilized while others continue to provision eggs after fertilization. The latter group has the functional equivalent of a mammalian placenta, but species vary in how well the placenta is developed and how much they provision young during development. Species also differ in how they choose mates, with some having males with elaborate ornamentation and courtship displays and others with no sex differences in coloration and no courtship. The integration of biology with the family tree is what will enable the investigators to infer when and in what order female provisioning and aspects of mate choice evolved. It is also possible to test whether the evolution of certain traits is associated with an acceleration or deceleration of how fast new species are formed. It will then be possible to test predictions derived from evolutionary theory for how the evolution of these traits are inter-related with one another. The family tree also enables the investigators to identify closely related species that differ in the presence or absence of placentas. These species pairs become the subjects of experiments in which they will perform more detailed studies of the biology of reproductive isolation, including assessments of multiple mating and the rate of evolution of reproductive isolation. The integration of work done at both levels will enable the investigators to detail how mating systems and mode of reproduction affect the evolution of reproductive isolation, how these different facets of speciation have interacted to shape the evolution of species in the family and how they affect the rate of speciation.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.

新物种是如何以及为什么进化的？ 复杂的器官，比如眼睛，是如何进化的？为什么会进化？ 这些现象发生的时间比我们的寿命长得多，使我们很难理解它们是如何发生的。 物种的定义是彼此不同，而不是相互繁殖。 不杂交可能是一个简单的问题，何时，何地或你选择与谁交配。 它也可能是由于未能产生可以生存和繁殖的后代。 今天的物种通常通过多种机制彼此分离，因此我们不知道它们最初是如何进化的。 类似地，复杂的器官就像机器，如果机器要工作，就必须有许多部件，并且必须很好地集成，但是这种复杂性是如何产生的呢？ 在每一种情况下，大自然最常呈现给我们的是最终产品，而没有任何关于它们是如何产生的线索;然而，有时大自然提供了一些物种，这些物种保留了足够的线索来研究这些过程是如何发生的，就像这个研究项目一样。 这项工作的一个影响涉及所研究的复杂器官。 这些研究人员正在研究胎盘的进化，并且在这样的背景下，他们可以将物种与缺乏胎盘或胎盘不太复杂的近亲进行比较。 这种多样性使他们能够解决胎盘的后果，包括它如何影响生育能力。该研究将加强对多层次（高中、大学和研究生）学生的培训，并向公众提供宣传。拟议的研究结合了两个层次的解决方案。首先，研究人员将研究Poeciliidae鱼类家族的所有物种，使他们能够确定进化变化的时间和顺序。 其次，他们将对该家族中的单个物种进行实验，以描述导致进化的机制。他们将对整个基因组进行测序，然后使用DNA序列重建家谱。 他们将描述树上每一个物种的生物学特征，包括雌性如何为幼崽提供食物，以及雄性和雌性如何选择与谁交配。 这些鱼都有活的幼鱼，但有些鱼在受精前完全提供卵子，而另一些鱼在受精后继续提供卵子。 后一组具有哺乳动物胎盘的功能等同物，但物种在胎盘发育的程度以及它们在发育过程中提供多少幼仔方面存在差异。 物种在选择配偶的方式上也有所不同，有些物种的雄性具有精心制作的交配和求偶展示，而另一些物种在颜色上没有性别差异，也没有求偶。 生物学与家谱的结合将使研究人员能够推断雌性供应和配偶选择方面的进化时间和顺序。 也有可能测试某些特征的进化是否与新物种形成的加速或减速有关。 然后，就有可能测试来自进化理论的预测，这些特征的进化是如何相互关联的。 家谱还使研究人员能够识别密切相关的物种，这些物种在胎盘的存在或不存在方面有所不同。 这些物种对成为实验的对象，在这些实验中，他们将对生殖隔离的生物学进行更详细的研究，包括评估多次交配和生殖隔离的进化速度。 在这两个层面上所做的工作的整合将使研究人员能够详细说明交配系统和繁殖模式如何影响生殖隔离的进化，物种形成的这些不同方面如何相互作用，以塑造物种在家庭中的进化，以及它们如何影响物种形成的速度。这个奖项反映了NSF的法定使命，并已被认为是值得支持的，通过评估使用基金会的知识价值和更广泛的影响审查标准。

项目成果

Molecular Signatures of Placentation and Secretion Uncovered in Poeciliopsis Maternal Follicles

• DOI: 10.1093/molbev/msaa121
• 发表时间: 2020-09-01
• 期刊: MOLECULAR BIOLOGY AND EVOLUTION
• 影响因子: 10.7
• 作者: Guernsey, Michael W.;van Kruistum, Henri;Baker, Julie C.
• 通讯作者: Baker, Julie C.

The evolution of the placenta in poeciliid fishes

• DOI: 10.1016/j.cub.2021.02.008
• 发表时间: 2021-05-10
• 期刊: CURRENT BIOLOGY
• 影响因子: 9.2
• 作者: Furness, Andrew I.;Avise, John C.;Reznick, David N.
• 通讯作者: Reznick, David N.

Mode of maternal provisioning in the fish genus Phalloceros : a variation on the theme of matrotrophy

石笔鱼属的母体供应模式：母体营养主题的变体

• DOI: 10.1093/biolinnean/blab121
• 发表时间: 2021
• 期刊: Biological Journal of the Linnean Society
• 影响因子: 1.9
• 作者: Zandonà, Eugenia;Kajin, Maja;Buckup, Paulo A;Amaral, Jeferson Ribeiro;Souto-Santos, Igor C;Reznick, David N
• 通讯作者: Reznick, David N