Evolutionary Proliferation: Diversification and its Contex in Neogastropod Molluscs

9706749 Vermeij进化扩张时代的特征是什么？在这种时候繁衍的支系有什么特征？这些基本问题推动了对选定的新生代新腹足类软体动物分支多样性的研究。巨大的形态和生态多样性，以及这一大群软体动物的出色化石记录，使新腹足动物成为研究进化繁殖的理想对象，进化繁殖是生命史上一种迄今鲜为人知但至关重要的现象。我们将研究进化历史明显不同的支系的分类、系统发育、分布和生态。在早先关于Rapanine鼠类和伪橄榄科的工作的基础上，将在鼠亚科Ocenebrinae和Muricinae，斗牛亚科Pisaniinae，Photinae和Sihonaliinae，以及片吸虫亚科Fasciolariidae中进行祖先-后代和姊妹群关系的分析。这些所谓的分支内部和之间的比较将集中在化石和活着的物种的贝壳特征上，这些特征将在世界上主要的博物馆收藏品中进行研究，以及从活着的代表身上获得的DNA序列。将在巴拿马的两个海岸进行观察，将贝壳形态与生活的方方面面联系起来，包括觅食、运动和防御。有待检验的假设包括：1)关键的创新以及反捕食性特征减少了物种形成的障碍，增加了一个分支的潜在表型范围；2)气候变暖的时间(始新世中晚期、渐新世晚期至中新世早期、上新世早期)有利于全球的多样性；3)中美洲海道从中新世晚期开始收缩，刺激了热带美洲的物种形成，但其他地方没有；4)冰川引起的气候波动刺激了高纬度分支的物种形成，从最晚的中新世开始。将利用姊妹组之间的多重比较、较长的时间间隔以及具有不同历史的地区之间的多重比较来评估这些物种形成和适应性多样化的内在和外在触发因素的作用。对多样化的研究很重要，不仅因为进化扩散仍然鲜为人知，还因为它与经济增长有着密切的相似之处。以经验为基础的关于生命历史的经济学观点可能会揭示人类经济的重要控制，并使进化科学和经济学社会科学之间的智力联系成为可能。

9706749 Vermeij Which circumstances characterize times of evolutionary expansion? What attributes characterize clades that proliferate at such times? These fundamental questions motivate the proposed study of diversification in selected clades of Cenozoic neogastropod molluscs. The great morphological and ecological diversity, as well as the excellent fossil record of this large group of molluscs make the Neogastropoda ideal for the study of evolutionary proliferation, an as yet poorly understood but crucially important phenomenon in the history of life. The taxonomy, phylogeny, distribution, and ecology of clades with apparently contrasting evolutionary histories will be studied. Building on earlier work with rapanine muricids and pseudolivids, analyses of ancestor-descendant and sister-group relationships will be conducted in the muricid subfamilies Ocenebrinae and Muricinae, the buccinid subfamilies Pisaniinae, Photinae, and Siphonaliinae, and the family Fasciolariidae. Comparisons within and between these purported clades will focus on shell characters of fossil and living species, to be examined in the major museum collections of the world, and on DNA sequences to be obtained from living representatives. Observations relating shell morphology to aspects of life including feeding, locomotion, and defense will be conducted on the two coasts of Panama. Hypotheses to be tested include the following: 1) key innovations as well as antipredatory traits reduce barriers to speciation and increase the range of potential phenotypes in a clade; 2) times of climatic warming (Middle to Late Eocene, Late Oligocene to Early Miocene, Early Pliocene) favor worldwide diversification; 3) constriction of the Central American seaway beginning in the Late Miocene stimulated speciation in tropical America but not elsewhere; 4) glacially induced climatic fluctuations stimulated speciation among high-latitude clades beginning in the latest Miocene. Multiple comparisons among sister-groups, a mong time intervals, and among regions with contrasting histories will be used to evaluate the roles of these intrinsic and extrinsic triggers of speciation and adaptive diversification. The study of diversification is important not only because evolutionary proliferation remains little understood, but also because of close parallels with economic growth. An empirically based economic perspective on the history of life may shed light on important controls of the human economy, and make possible intellectual links between evolutionary science and the social science discipline of economics.