Historical Phylogeny of Tahitian Partula, an Almost Extirpated Land Snail Fauna

海洋岛屿对进化生物学家和保护生物学家都有特别的兴趣。 本土植物和动物在这些岛屿上与世隔绝地进化，并为基本的进化过程提供了详细的见解。 然而，它们的特点是缺乏发达的防御机制，并且特别容易受到引入的捕食者的伤害。利用博物馆标本的DNA分析，我们的目标是重建塔希提岛（法属波利尼西亚）严重威胁辐射的陆生蜗牛的进化史。 这种太平洋岛屿蜗牛动物群最近被一种引进的掠食性陆生蜗牛逼到了灭绝的边缘。 我们博物馆的样本早于这种捕食者的出现，在它们的DNA中，它们共同包含了一个谱系记录，我们可以用它来修改传统的基于贝壳的分类法，并确定所有这些蜗牛是如何在这样一个小的、地质学上年轻的岛屿上进化的。我们的研究将具有实用价值，有助于优先考虑正在进行的保护和恢复工作。 已经与伦敦动物学会的人员建立了合作协议，这些人员参与监督圈养的塔希提蜗牛动物园种群和拯救最后的野生种群。我们的共同目标是通过获得现存野生和圈养种群的DNA图谱，将其与我们的历史塔希提岛数据库相参考，将残留的野生和圈养种群置于其适当的进化背景中：即先前完整的动物群。 初步的努力得到了广泛的宣传（例如，http://whyfiles.org/shorties/151land_snail/index.html). 我们预计，我们的研究将感兴趣的那部分公众热衷于高调的保护生物学问题。

Oceanic islands hold particular interest for both evolutionary andconservation biologists. Native plants and animals evolved in isolation onthese islands and provide detailed insights into fundamental evolutionaryprocesses. However, they characteristically lack well-developed defensivemechanisms and are exceptionally vulnerable to introduced predators. UsingDNA analyses of museum specimens, we aim to reconstruct the evolutionaryhistory of a critically threatened radiation of land snails from Tahiti(French Polynesia). This Pacific island snail fauna has recently beendriven to the brink of extinction by an introduced predatory landsnail. Our museum samples predate the introduction of the predator and, intheir DNA, they collectively contain a genealogical record that we can useto revise the traditional shell-based taxonomy and to determine how allthese snails evolved on such a small, geologically young, island.Our research will have practical value in helping to prioritize on-goingconservation and rehabilitation efforts. Collaborative agreements havebeen established with Zoological Society of London personnel involved inoverseeing captive Tahitian snail zoo populations and in saving the lastremnant wild populations. Our shared aim is to place the remnant wild andcaptive populations into their proper evolutionary context: that of thepreviously intact fauna, by obtaining DNA profiles of extant wild andcaptive populations that will be referenced with our historical Tahitiandatabase. Preliminary efforts have received considerable general publicity(e.g., http://whyfiles.org/shorties/151land_snail/index.html). Weanticipate that our research will be of interest to that fraction of thepublic keen on high-profile conservation biology issues.