在一种引入的中,地理上的斜坡尺寸的快速演变
R B Huey1, G W Gilchrist, M L Carlson
1Department of Zoology, University of Washington, Box 351800, Seattle, WA 98195-1800, USA. hueyrb@u.washington.edu
概括
果Drosophila subobscura在二十年内在北美演化出了可预测的翅膀长度下降,反映了它祖先的旧世界模式. 然而,驱动这种进化的特定翅膀部分不同,显示了偶然的进化路径.
科学领域:
- 进化生物学是进化的生物学.
- 人口遗传学 人口遗传学
- 规格 规格 规格 规格
背景情况:
- 侵袭性果,Drosophila subobscura,在20年前引入北美,提供了一个独特的模型来研究地理变异的进化.
- 在其原始的旧世界范围,D. subobscura在翅膀长度上表现出明显的斜坡,随着度的增加而增加.
- 在北美进行的初步研究显示,在引入后的十年内,没有显著的翅膀长度下降.
研究的目的:
- 研究一种新引入的物种进化的速度和可预测性.
- 要确定在北美Drosophila subobscura种群中是否演变出一个翅膀长度的地理斜坡.
- 为了比较进化的向与旧世界人口的祖先向.
主要方法:
- 监测二十年来北美人口的翅膀长度变化.
- 将开发的克林与旧世界人口的现有数据进行比较.
- 分析不同翼段对临床变化的贡献.
主要成果:
- 在20年内,在北美出现了翅膀长度的显著地理斜率.
- 进化后的斜线在很大程度上与在旧世界观察到的祖先斜线相结合.
- 大陆范围的形态进化的速度非常快.
- 不同的翅膀部分导致了新世界和旧世界的,表明了偶然的进化.
结论:
- 在Drosophila subobscura翅膀长度的地理变异的演变是可预测的.
- 具体的进化途径 (即哪些翅膀部分发生变化) 是偶然的.
- 在引入物种中,快速的大陆规模的进化是可能的.
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