来自中国的一种类似Archaeopteryx的热足动物,也是Avialaelae的起源
1College of Life Science, Linyi University, Shuangling Road, Linyi City, Shandong 276005, China. xingxu@vip.sina.com
Nature
|July 29, 2011
概括
考古鸟类可能不是最早的鸟类. 来自中国的新化石证据表明,它属于Deinonychosauria,这是一个与真正的飞鸟类不同的群体,挑战其在鸟类进化中的作用.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 脊椎动物动物学 脊椎动物动物学
背景情况:
- * 考古鸟类传统上被认为是最基本的鸟类,对于理解鸟类起源至关重要.
- *最近发现的衍生品曼尼拉普托拉人已经提出了关于Archaeopteryx绝对的鸟类地位的问题.
研究的目的:
- * 来描述一个新的Archaeopteryx类型的中国的热足动物化石.
- *重新评估Archaeopteryx在热足类恐龙中的遗传学位置.
- *重新评估以前被认为是早期鸟类 (Avialae) 的诊断特征.
主要方法:
- * 进行了综合性遗传学分析,纳入了新的化石分类.
- *分析了新型热足动物的形态特征,并将其与已知的maniraptorans和早期avialans进行了比较.
主要成果:
- *新的热足动物表现出以前被认为是Avialae特有的特征,例如长的前肢,但现在被理解为更广泛的群体Paraves的特征.
- * 遗传学分析,包括新分类,将Archaeopteryx置于Deinonychosauria中,而不是最基本的鸟类.
- *这种重新分类是基于初步的统计支持,但表明了理解的重大转变.
结论:
- * 这一发现挑战了长期以来关于Archaeopteryx的观点,认为它是鸟类起源的核心.
- *如果得到证实,这个遗传学假设需要重新评估祖先的鸟类状况.
- *这项研究强调了进化理解的动态性质,并通过新的化石发现.
相关概念视频
Phylogeny
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire kingdom.
What is Evolutionary History?
Scientists record evolutionary history by analyzing fossil, morphological, and genetic data. The fossil record documents the history of life on Earth and provides evidence for evolution. However, both fossil and living organisms offer evidence that outlines Earth’s evolutionary history.
The Evidence for Evolution
Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
The Fossil Record
The fossil record documents only a small fraction of all organisms that have ever inhabited Earth. Fossilization is a rare process, and most organisms never become fossils. Moreover, the fossil record only exhibits fossils that have been discovered. Nevertheless, sedimentary rock fossils of long-lived, abundant, hard-bodied organisms dominate the fossil record. These fossils offer valuable information, such as an organism's physical form, behavior, and age. Studying the fossil record helps...
Convergent Evolution
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
Viruses of Archaea
Archaeal viruses play a crucial role in the ecosystems of extremophilic archaea, particularly those belonging to the phyla Euryarchaeota and Crenarchaeota. By shaping host evolution and facilitating gene transfer, these viruses influence microbial communities and contribute to genetic diversity in extreme environments. The archaea they infect thrive in acidic hot springs and hydrothermal vents characterized by high temperatures and low pH. Archaeal viruses exhibit remarkable structural...


