关于飞行羽毛数量和形状的功能限制
Yosef Kiat1, Jingmai K O'Connor1
1Negaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL 60605.
概括
灭绝的恐龙的羽毛形态揭示了飞行进化的关键见解. 分析表明,恐龙飞行的起源是单一的,早期的羽毛翼进化可能没有在化石中保存.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 生物力学 生物力学
背景情况:
- 运动是有机体形态和进化多样化的主要驱动力.
- 关于pennaraptoran恐龙中飞行机动 (飞行) 的起源和演变仍在争论中,关于各种种类的飞行能力的证据相互矛盾.
- 关于羽毛鸟飞行潜力的先前研究往往忽视了翅膀羽毛结构和形态学的关键作用.
研究的目的:
- 研究现存鸟类的羽毛形态和运动能力之间的关系.
- 根据羽毛的特征,评估已灭绝的pennaraptoran恐龙,特别是anchiornithines和*Microraptor*的飞行能力.
- 为了确定飞行机动是否在pennaraptoran恐龙中产生了一次或多次.
主要方法:
- 在现存鸟类的大数据集中分析remex (翼) 和rectrix (尾) 羽毛的数量和形状.
- 羽毛特征 (数量,主要羽翼不对称) 和运动能力之间的相关性分析.
- 对中纪鸟类,微猛龙和鸟类的化石羽毛进行了比较形态分析,并提供了现存的鸟类羽毛数据.
主要成果:
- 现存鸟类的羽毛数量和主要羽翼不对称性与运动能力有很强的相关性,表明功能限制.
- 中世鸟类和微猛龙表现出羽毛形态与飞行能力一致,类似于现存的鸟类.
- 安基欧尼丁表现出显著不同的remex形态,提供了强有力的证据,反对在这个分类.
结论:
- 这项研究支持恐龙飞行的单一起源.
- 羽毛形态为评估已灭绝的种群的运动能力提供了可靠的代理.
- 羽翼进化的早期阶段可能没有在当前的化石记录中得到代表.
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