Modularity and Metamorphosis: the effect of complex life history on cranial integration

模块化和变形：复杂的生活史对颅骨整合的影响

• 批准号: NE/J012432/1
• 负责人: Anjali Goswami
• 金额: $ 6.32万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2012
• 资助国家: 英国
• 起止时间: 2012 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FJ012432%2F1
• 关键词: Modularity; Metamorphosis; effect; complex; life

What drives large-scale patterns of morphological evolution? Natural selection acts upon existing variation, the raw material of evolution, to shape the diverse organisms that we see and study today, but what shapes variation? Development is often presented as a major influence on morphological variation, but linking developmental effects into large-scale models of evolution is difficult because comparative developmental data is relatively uncommon. Quantitative data, specifically measurements of the shapes of organisms and the interactions among parts of an organism, has the potential unify disparate fields of evolutionary study, from genetics to development and morphology, into a single framework. Quantification of organismal shape (morphology), during development has been hindered by difficulties in obtaining measurements from small, immature specimens, which often can lose their shape during preparation. However, in recent years, increased access to high-resolution imaging machines, such as CT scanners, and advanced visualization and digitising software has improved the possibility of gathering large volumes for rigorous statistical analyses of changes during development. The topic of morphological integration is among those that are highly quantitative and will benefit from the incorporation of comparative developmental data. These terms relate to the intuitive idea that complex organisms have many parts with varying interrelationships. Simply, a change in a foot bone would be expected to have more effect on other parts of the foot than they do on, for example, the nose. Delineating the relationships of different parts of an organism can provide novel and unpredicted information on the genetic, developmental, and functional influences on an organism's morphology, and these patterns of trait relationships are termed morphological integration. Much research on morphological integration has focused on the mammalian skull and jaws and has shown a number of interesting results. First, mammal skulls are formed of six relatively distinct regions, and this pattern of skull integration is observed across mammals, from monkeys to mice. Second, this pattern may reflect developmental interactions, such as tissue origin, as the skull is a developmentally complex structure. Third, patterns of skull integration change through development, from the early stages immediately after birth until subadulthood or adulthood. This last feature is complicated, but there is some evidence that differences in reproductive strategies, specifically between marsupials (such as kangaroos) and placentals (such as dogs or humans) are reflected in the changes in skull integration that occur during ontogeny. While most research on morphological integration in vertebrates has been conducted on mammals, especially primates and rodents, there is little comparative data on other vertebrates with which to judge whether mammalian patterns are unusual, or simply reflect a more ancestral condition. Furthermore, the diversity of developmental strategies in mammals is far less than that observed across vertebrates. In this study, we will examine morphological integration in the skull of a vertebrate with a very different developmental strategy to that seen in mammals: the African clawed frog, which undergoes metamorphosis from a larval tadpole to a froglet to an adult frog. We will use CT scanning to gather large numbers of specimens from three stages of development to test if skull integration is similar in frogs and mammals, if skull integration changes during frog development, including metamorphosis, and if skull integration in adult frogs reflects whether bones are formed before, during or after metamorphosis. The results of this study, in comparison with existing data for mammals, will form the basis for a more comprehensive study of developmental integration across tetrapods.

是什么推动了形态进化的大规模模式？自然选择作用于现有变化，即进化的原材料，以塑造我们今天看到和研究的各种生物，但是什么塑造了变化？发展通常是对形态变异的主要影响，但是将发展效果与大规模进化模型联系起来很困难，因为比较发育数据相对罕见。定量数据，特别是对生物体形状的测量以及生物体部分之间的相互作用，具有潜在的统一进化研究的统一领域，从遗传学到发育和形态，到一个框架。在发育过程中的生物形状（形态）的量化受到了从小而未成熟的标本获得测量的困难，这些标本通常在制备过程中可能会失去其形状。但是，近年来，增加了获得高分辨率成像机（例如CT扫描仪）以及高级可视化和数字化软件的访问，提高了收集大量量的可能性，以对开发过程中进行严格的统计分析。 形态整合的主题是高度定量的，将从合并比较发展数据中受益。这些术语与直观的想法有关，即复杂的生物具有许多相互关系的部分。简而言之，脚骨的变化预计会对脚的其他部位产生比例如鼻子更大的影响。描述生物体不同部分的关系可以提供有关生物体形态的遗传，发育和功能影响的新颖和未预测的信息，而这些性状关系的这些模式称为形态学整合。关于形态整合的许多研究集中在哺乳动物的头骨和下巴上，并显示了许多有趣的结果。首先，哺乳动物头骨由六个相对不同的区域形成，从猴子到小鼠，跨哺乳动物都观察到这种颅骨整合模式。其次，这种模式可能反映了发育相互作用，例如组织起源，因为头骨是一种发育复杂的结构。第三，颅骨整合的模式通过发育发生了变化，从出生后的早期阶段到亚产物或成年。最后一个特征很复杂，但是有一些证据表明，生殖策略的差异，特别是在有袋动物（例如袋鼠）和胎盘（例如狗或人类）之间的差异反映在个体发育过程中发生的头骨整合的变化中。 虽然大多数关于脊椎动物形态整合的研究是对哺乳动物，尤其是灵长类动物和啮齿动物进行的，但对其他脊椎动物的比较数据很少，可以判断哺乳动物模式是不寻常的，或者只是反映了更祖先的条件。此外，哺乳动物中发育策略的多样性远低于脊椎动物的观察到。在这项研究中，我们将研究脊椎动物的头骨中的形态整合，其发育策略与哺乳动物中的发育策略截然不同：非洲爪蛙，从幼虫t到青蛙到成年青蛙，它经历了变质。我们将使用CT扫描来收集来自三个发育阶段的大量标本，以测试颅骨和哺乳动物中的头骨整合是否相似，是否在青蛙发育过程中的头骨整合发生变化，包括变态，以及成年青蛙中的头骨整合是否反映了骨头是否反映了骨骼是否在变质之前，期间或后变态后形成。 与哺乳动物的现有数据相比，这项研究的结果将构成对四足动物的发育整合的更全面研究的基础。

项目成果

The macroevolutionary consequences of phenotypic integration: from development to deep time.

• DOI: 10.1098/rstb.2013.0254
• 发表时间: 2014-08-19
• 期刊: Philosophical transactions of the Royal Society of London. Series B, Biological sciences
• 作者: Goswami A;Smaers JB;Soligo C;Polly PD
• 通讯作者: Polly PD

Do Developmental Constraints and High Integration Limit the Evolution of the Marsupial Oral Apparatus?

• DOI: 10.1093/icb/icw039
• 发表时间: 2016-09
• 期刊: Integrative and comparative biology
• 影响因子: 2.6
• 作者: Goswami A;Randau M;Polly PD;Weisbecker V;Bennett CV;Hautier L;Sánchez-Villagra MR
• 通讯作者: Sánchez-Villagra MR

An information theoretic approach to cranial modularity with 3-D morphometric data

利用 3D 形态测量数据进行颅骨模块化的信息理论方法

• 发表时间: 2014
• 作者: Goswami, A