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现代神秘物种可以在化石记录中检测到吗? 一个关于阿加米德的案例研究
Till Ramm1,2,3,4, Jaimi A Gray5, Christy A Hipsley1,2,6
1Sciences Department, Museums Victoria, 11 Nicholson Street, Carlton, Victoria, 3053, Australia.
Systematic biology
|November 22, 2024
概括
由于神秘的物种,化石爬行动物 (状动物) 的识别具有挑战性. 孤立的头骨骨可以识别属和推断生态,但往往低估了物种多样性,影响了生物多样性比较.
科学领域:
- 古生物学的古生物学
- 动物学 动物学
- 进化生物学 进化生物学
背景情况:
- 比较现存和灭绝的生物多样性依赖于化石和现代种类的可比分类学.
- 现代物种划分通常使用分子数据,使化石的分类仅基于形态学而复杂化.
- 形动物 (和蛇) 的神秘多样性正在增加,但骨科的比较知识有限.
研究的目的:
- 评估分离的头骨骨 (额头和) 对于 agamid 的分类和生态分类的有用性.
- 为了评估这些骨头的形态变异性的一致性,作为灭绝物种丰富性的代理.
- 测试化石样本限制 (样本大小减少,数据不完整) 对分类准确性的影响.
主要方法:
- 在现存的澳大利亚和巴布亚新几内亚的14个属中的238个个体上利用了3D几何形态测量.
- 分析了孤立的额头和大骨,以推断分类学和生态亲和关系.
- 通过减少样本大小和里程碑的完整性来模拟化石样本的条件.
主要成果:
- 额头和大骨在通用水平上是诊断的,对于推断微生态和古生态学是有用的.
- 在物种层面的多样性很可能被低估了,在30-40%的物种对之间存在显著的形状相似性.
- 种内形态变异性在物种和骨之间是一致的,作为灭绝物种多样性的代理.
- 减少样本大小和里程碑完整性降低了分类准确性和增加了形态差异变异.
结论:
- 单独的骨头骨头在agamids是有价值的基因识别和古生态推断,但可能低估了物种多样性.
- 现代物种界限的可转移性到阿格米德的化石记录是可疑的,特别是在不完整的化石数据下.
- 建立适当的基于形态的分类学或生态分类对于准确比较现存和灭绝的生物多样性至关重要.
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