有证据表明,在蜂鸟中,性变态的生态原因是蜂鸟的生态原因
E J Temeles1, I L Pan, J L Brennan
1Department of Biology, Amherst College, Amherst, MA 01002, USA. ejtemeles@amherst.edu
Science (New York, N.Y.)
|July 21, 2000
概括
紫喉海蜂鸟的性二态性质是由两种Heliconia花种在生态上驱动的. 这些植物的花专业化和地理位置的替代形成了男性和女性的单独的账号大小.
科学领域:
- 生态生态学 生态生态学
- 进化生物学 进化生物学
- 鸟类学 鸟类学是一门学科.
背景情况:
- 性二态,特别是在形态上,往往缺乏明确的生态因果关系.
- 蜂鸟表现出多样化的嘴巴形状,表明它们适应了特定的花资源.
研究的目的:
- 为了研究紫喉海蜂鸟的嘴巴形态中的性二态的生态驱动因素.
- 为了测试一种假设,即与特定的Heliconia花种的共同进化导致了这只蜂鸟的单元二态.
主要方法:
- 对紫海蜂鸟及其主要食物来源的观测研究,两种Heliconia物种.
- 在雄性和雌性蜂鸟中分析了比尔形态.
- 在两个Heliconia物种上测量每个性别的养效率.
- 对Heliconia物种分布的地理变异和相关的蜂鸟形态的检查.
主要成果:
- 雄性和雌性紫海表现出明显的比尔形态,这与两个Heliconia物种的形状相对应.
- 每个性别都在Heliconia物种上表现出更高的养效率,这些物种的花朵尺寸最适合各自的嘴巴尺寸.
- 一种Heliconia物种被另一种物种的地理替代与花二态的发展相关,其中一种形态与雄性账单相匹配,另一种形态与雌性账单相匹配.
结论:
- 生态因果关系,特别是花专业化,是紫海蜂鸟的嘴巴形态中的性二态的重要驱动因素.
- 观察到的比尔二态是适应利用不同的花资源,每个性别都专注于特定的Heliconia物种.
- 蜂鸟和植物之间的共同进化过程可以导致两性之间明显的形态差异.
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