在反阿尔克斑体中发生交配,以及体体内受精的起源
John A Long1, Elga Mark-Kurik2, Zerina Johanson3
11] School of Biological Sciences, Flinders University, 2100, Adelaide, South Australia 5001, Australia [2] Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, California 9007, USA [3] Museum Victoria, PO Box 666, Melbourne, Victoria 3001, Australia.
Nature
|October 21, 2014
概括
在的脊椎动物中,内部受精可能是原始的. 关于古老的抗体体中有扣子的新化石证据表明,所有体的特征是内部受精,这挑战了以前的进化假设.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 脊椎动物繁殖 脊椎动物繁殖
背景情况:
- 脊椎动物 (gnathostomes) 的繁殖通常是外部或内部受精.
- 内部受精通常被认为是从外部受精进化的,而不是相反.
- 体动物,一个灭绝的脊椎动物群,表现出暗示内部受精的特征,但最早的群体如反体缺乏证据.
研究的目的:
- 为了研究反鱼的生殖生物学,一个基底的平原体群.
- 为了确定内部受精是否是所有胎皮动物的特征.
- 重新评估早期脊椎动物受精策略的进化轨迹.
主要方法:
- 分析了反的皮肤结构的化石.
- 扣子和相关板块与其他斑皮体群 (例如,ptyctodonts) 的比较形态.
- 根据解剖学证据推断生殖行为.
主要成果:
- 雄性前拥有皮肤扣子,雌性具有配对的皮肤板.
- 这些与骨盆无关的结构促进了交配.
- 抗的形态是同类的发现在更多的衍生 placoderms像ptyctodonts.
结论:
- 内部受精很可能是所有白皮动物的特征.
- 在现存的水生体中,外部受精和繁殖可能是从内部受精进化而来的,颠覆了以前的进化模型.
- 这些发现支持了体体内内受精的原始性质,以及斑皮动物的过生态地位.
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