Collaborative Research: Molecular Systematics of the Avian Order Gruiformes

新墨西哥州立大学的Peter Houde博士和南伊利诺伊大学的Carey Krajeski博士获得了一项合作拨款，以确定已知的最多样化的鸟类群体之一的谱系，即龟形目。将通过比较几个基因的DNA序列来评估该目内家族的谱系关系。过去的解剖分化和地理起源模式将从现存物种的特征在谱系上发生变化的模式中推断出来。主要群体的年龄将根据他们DNA序列之间的差异水平来估计。单独的基因和解剖特征可能会因为“融合”而提供关于家谱的误导性信息，因此将从大量独立的数据中重建粗线条的家谱，所有这些数据都将评估其与其他数据的一致性。不一致的数据子集将被仔细检查功能和发育相关性。这反过来将阐明谱系之间的融合过程，无论是在基因水平上还是在解剖学水平上。对于了解鸟类起源的时间和地理位置，虾形目动物具有特别重要的意义，因为它们极其多样化，地理上分布广泛。许多家族似乎是很久以前恐龙时代的遗物，当时大陆的布局与今天截然不同。Gruiform提供了许多融合的例子，为研究导致融合的过程提供了一个无与伦比的机会。可能没有其他脊椎动物的关系如此鲜为人知，但在解剖学特征方面有相当丰富的数据。也有初步证据表明在基因水平上存在趋同，这一现象在以前的研究中甚至几乎没有得到承认。因此，这个小组提供了一个真正独特的机会来理解随着时间的推移遗传和形态变化之间的相关性。

DEB-0108656Carey W. KrajewskiA collaborative grant has been awarded to Dr. Peter Houde at New Mexico State University and Dr. Carey Krajewski at Southern Illinois University to determine the genealogy of one of the most diverse groups of birds known, the Order Gruiformes. Genealogical relationships of families within the order will be assessed by comparing DNA sequences of several genes. Past patterns of anatomical divergence and geographic origins will be inferred from the pattern by which characteristics of living species have changed genealogically. The ages of major groups will be estimated from levels of difference between their DNA sequences. Individual genes and anatomical characters can provide misleading information about genealogy because of "convergence", so gruiform genealogy will be reconstructed from a large body of independent data, all of which will be evaluated for its consistency with the rest. Subsets of the data that are inconsistent will be scrutinized for functional and developmental correlates. This, in turn, will elucidate processes of convergence between lineages, both at the level of genes and that of anatomy. Gruiformes have singular importance in understanding the timing and geography of bird origins in general, because they are extremely diverse and geographically widespread. Many families appear to be relics of the long bygone Age of Dinosaurs when the continents were arranged quite differently than they are today. Gruiforms present many examples of convergence, providing an unparalleled opportunity for studying the processes that cause it. There is probably no other group of vertebrate animals whose relationships are so poorly understood, yet for which there is a comparable wealth of data on anatomical characteristics. There is also preliminary evidence for convergence at the genetic level, a phenomenon that has barely even been acknowledged in previous research. Thus, this group presents a truly unique opportunity for understanding the correlation between genetic and morphological change through time.