来自哥伦比亚的新米奥森时代的石类遗骸和美国新生代草食者协会的生态结构
Andrew J McGrath1, Darin A Croft2, Juan D Carrillo3
1Rincon Consultants, Inc., 319 E Carrillo St, Santa Barbara, California, 93106, USA. amcgrathpaleo@gmail.com.
BMC zoology
|August 20, 2025
概括
来自哥伦比亚的新化石揭示了南美哺乳动物在美国大生物交换 (GABI) 之前更为多样化. 在GABI后的灭绝大大减少了这种多样性,影响了现代生态系统.
科学领域:
- 古生物学的古生物学
- 生态生态学 生态生态学
- 南美洲哺乳动物进化
背景情况:
- 哥伦比亚的中米欧纪La Venta动物群提供了关于大美洲生物交换 (GABI) 之前生态系统的见解.
- 展示了来自拉文塔的型动物 (Villarroelia totoyoi,Mesolicaphrium sanalfonense,Theosodon) 的新化石材料.
- GABI促进了北美和南美之间的动物交换,导致了血统的扩散和灭绝.
研究的目的:
- 在GABI之前和之后分析11个北美和南美哺乳动物草食动物的生态形态多样性.
- 了解GABI对哺乳动物草食群体的影响.
主要方法:
- 对中大型哺乳动物草食动物的生态形态学分析.
- 身体尺寸,牙形态和食高度的评分,以进行动物比较.
主要成果:
- 获得了关于M. sanalfonense的落叶牙和La Venta Theosodon下的新数据.
- 在GABI前,南美动物表现出比北美动物更大的生态形态多样性.
- 普莱斯托时代后的动物群表现出与普莱斯托时代前的南美动物群相似的多样性,但普莱斯托时代末期的灭绝减少了现代动物群的多样性.
结论:
- 新的光型化石提供了形态洞察力,但不能解决系统性问题.
- 在GABI前的多样性差异与南美洲的树木和类属有关,这些属在北美不存在.
- 在GABI之后,一些树木和海普塞隆顿的种类在北美成功,但许多海普塞隆顿的血统灭绝了,这表明牙形态在捕捉完整的饮食多样性方面存在局限性.
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