DISSERTATION RESEARCH: The role of biotic association in the evolution of a megadiverse marine bivalve clade

地球上巨大的生物多样性不仅为人类提供了宝贵的生物资源，而且是我们高度相互依存的生态系统的重要组成部分。这种巨大的生物多样性是如何产生的，这仍然是生物学的一个核心问题。虽然生命树的大部分可以通过非生物(非生物)过程产生，如气候变化或构造运动，但一些最引人注目的多样性来自物种之间的生物相互作用。当代海洋谱系的进化研究通常是在非生物假设检验的背景下进行的，在建立包括有意义的生物观点的综合框架方面总体上落后于陆地研究。这项拟议的研究通过研究超多样性蛤类群Galeommatoidae的进化来解决这一不足。它是一个特别适宜的群体，因为它包含大量自由生活和共生(与宿主共生)的物种，因此易于采用比较方法。自由生活和共生的文蛤的进化路径都受到非生物因素的影响，但共生物种受到另一个生物因素的影响：它们与寄主的生态相互作用。通过比较这两个群体的进化模式，可以评估非生物和生物因素在推动这一物种丰富的海洋生物谱系多样化方面的相对作用。该倡议涉及与国家和国际博物馆收藏品的广泛合作。一名研究生正在接受系统发育、形态和宏观进化分析方面的深入研究培训。四名本科生一直在接受分子系统学技术培训。参与该项目的许多标本将被存放在密歇根大学动物、生态和进化生物学博物馆。这名研究生和另外两名本科生将接受培训，使博物馆藏品计算机化，并管理电子分类数据库。此外，选定的盖氏双壳类文蛤的生物多样性数据将有助于动物多样性网，这是公共生物多样性信息的主要来源，也直接输入在线生命百科全书。ADW也是一个免费的生物多样性数据库，允许学生/研究人员在生命之树上进行比较荟萃分析。

The enormous biodiversity on earth not only provides humans valuable biological resources, but also serves as a crucial component of our highly interdependent ecosystem. How this great biodiversity is generated remains a central question of biology. While much of the tree of life can be generated through abiotic (non-living) processes, such as climate change or tectonic movements, some of the most striking diversities arise from biotic interactions between species. Evolutionary studies of contemporary marine lineages are typically framed within abiotic hypothesis-testing contexts and have collectively lagged behind terrestrial studies in developing an integrated framework that includes a meaningful biotic perspective. The proposed research addresses this deficiency by studying the evolution of the hyperdiverse clam group Galeommatoidea. It is a particularly apt group because it contains large numbers of free-living as well as symbiotic (living with a host) species and is therefore amenable to comparative approaches. The evolutionary pathways of both free-living and symbiotic clams are affected by abiotic factors, but the symbiotic species are influenced by an additional biotic factor: their ecological interactions with hosts. By comparing the evolutionary patterns of the two groups, the relative roles of abiotic and biotic factors in driving the diversification of this species-rich marine lineage can be assessed.The proposed research complements the NSF-funded ?Assembling the Bivalve Tree of Life? initiative and involves extensive collaboration with national and international museum collections. One graduate student is receiving in-depth research training in phylogenetic, morphological and macroevolutionary analysis. Four undergraduate students have been receiving training in molecular phylogenetic techniques. Many specimens involved in the project will be deposited into the Museum of Zoology, Ecology and Evolutionary Biology, University of Michigan. The graduate student and two other undergraduate students will be trained to computerize museum collections and manage electronic taxonomic databases. In addition, biodiversity data of selected galeommatoidean clams will be contributing to the Animal Diversity Web (ADW), a premier source of public biodiversity information that also directly feeds into the online Encyclopedia of Life. The ADW also serves as a free biodiversity database that allows students/researchers to conduct comparative meta-analysis across the tree of life.