昆虫食草动物驱动植物种群的实时生态和进化变化
Anurag A Agrawal1, Amy P Hastings, Marc T J Johnson
1Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA. agrawal@cornell.edu
Science (New York, N.Y.)
|October 9, 2012
概括
昆虫食草动物显著影响植物进化. 抑制本地植物上的昆虫导致草食动物抵抗力下降和竞争能力增加,在实时田间种群中显示出快速,独立的进化变化.
科学领域:
- 生态生态学 生态生态学
- 进化生物学 进化生物学
- 植物科学 植物科学
背景情况:
- 昆虫食草被认为是影响植物生态和进化的关键驱动因素.
- 了解草食动物施加的选择性压力对于植物种群动态至关重要.
研究的目的:
- 研究昆虫草食对本地植物物种Oenothera biennis的生态和进化后果.
- 确定抑制昆虫如何影响植物防御,竞争能力和进化轨迹.
主要方法:
- 涉及Oenothera biennis复制种群的实地实验与受控的昆虫抑制.
- 大约12,000个人的比较基因型和表型,以评估进化变化.
- 分析了种子掠食,物种间竞争,开花时间和水果基素含量.
主要成果:
- 抑制昆虫减少了种子掠食,改变了物种间的竞争动态.
- 保护的植物种群显示,随着时间的推移,食草动物耐药性下降,这与开花时间的变化和果实ellagitannins的减少有关.
- 在受昆虫保护的土地上,植物的竞争力显著增加.
- 观察了植物耐药性和竞争能力的独立实时演变.
结论:
- 昆虫食草动物施加强大的选择性压力,塑造了植物的进化.
- 草食压力的放松可以导致植物防御和竞争战略的快速,独立的进化转变.
- 草食的间接影响,通过改变植物竞争的媒介,也导致了进化分歧.
相关概念视频
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