Dissertation Research: The Evolution of Reproductive Isolation in Neotropical Costus (Costaceae)

0104847SchemskeThe拟议的研究调查的机制，有助于在两个密切相关的物种边界，新热带区生姜。研究物种生活在中美洲的同一热带森林中，在同一时间开花，主要由同一种蜂鸟授粉。然而，它们在许多叶和花的特征上不同，而且永远不会产生杂交后代。是什么让这些物种与众不同？这项研究将使用实验性杂交、实地观察和分子遗传技术来回答这个问题。到目前为止收集的信息表明，一个方向的杂交失败是因为花粉生长受到抑制，而另一个方向的繁殖失败是由于花粉无法生长到足够长的距离以产生种子。研究结果将最终显示微妙的，但有效的手段，让不同的物种共存。 自然界最大的奥秘之一是物种如何保持其独特的特征。如果没有防止杂交的机制，物种的多样性将远远低于我们今天所看到的。了解这些生殖障碍如何在自然种群中发挥作用，为农业新品种的开发和生物多样性的保护和管理提供了有用的见解。

0104847SchemskeThe proposed research investigates the mechanisms that contribute to species boundaries in two closely related, Neotropical gingers. The study species live in the same tropical forests in Central America, flower at the same time and are pollinated largely by the same species of hummingbird. Yet they differ in a number of leaf and flower characters, and never produce hybrid offspring. What keeps these species distinct? The research will use experimental crosses, field observations and molecular genetic techniques to answer this question. The information gathered thus far suggests that crosses in one direction fail because pollen growth is inhibited, while reproductive failure in the other direction is caused by the inability of the pollen to grow far enough to produce seeds. The research findings will ultimately show the subtle, but effective means that allow different species to coexist. One of the great mysteries of Nature is how species retain their distinctive characteristics. Without mechanisms to prevent interbreeding, the diversity of species would be far less than what we see today. Understanding how these reproductive barriers function in natural populations provides insights useful for both the development of new agricultural varieties and for the conservation and management of biodiversity.