概括
最古老的知名企化石来自新西兰,以前被认为是早期的伊欧纪,现在可以追溯到早期的米欧纪. 这次重新评估对早期企进化和化石范围的理解进行了修订.
科学领域:
- 古生物学的古生物学
- 新生态学新生态学
- 生物分层学是生物分层学.
背景情况:
- 一个新西兰化石,长期以来被认为是最古老的企,可以追溯到早期的伊欧纪 (Heretaungan),已经经历了重新评估.
- 之前的研究表明,Palaeeudyptes antarcticus的时间范围很广,从古晚期到古早期.
研究的目的:
- 重新评估一个关键的新西兰企化石的年龄.
- 为了澄清早期企物种的时间分布,特别是Palaeeudyptes antarcticus.
- 重新评估化石企标本的约会精度.
主要方法:
- 新西兰地质调查局对新西兰样本进行了地质再分析.
- 化石企发生的比较生物层级图分析.
- 审查现有的古生物学数据和约会方法.
主要成果:
- 新西兰标本的年龄已经从早期的伊欧纪到早期的米欧纪进行了修订.
- 已知最古老的企化石现在被认为是来自Eocene晚期.
- 以前分配给Palaeeudyptes antarcticus的广泛的地平面范围被认为是不可接受的.
- 其他几种化石企标本的约会时间不如以前报道的精确.
结论:
- 新西兰标本的重新约会需要对最早的企化石记录进行修订.
- 帕拉伊迪普特斯南极洲的时间分布需要进一步调查,而且可能更受限制.
- 对古生物学标本的约会方法进行批判性审查对于准确的进化研究至关重要.
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