Paps Jordi
School of Biological Sciences, University of Essex, Colchester, Essex CO4 3SQ, UK.
Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.
Integr Comp Biol. 2018 Oct 1;58(4):654-665. doi: 10.1093/icb/icy036.
What makes an animal? To find the answer we need to integrate data from disciplines such as phylogenetics, paleontology, ecology, development, anatomy, and physiology, as well as molecular biology and genomics. Knowledge of which groups branched before and after the origin of animals is essential. Recent advances in molecular phylogenetics, together with the discovery of new eukaryotic lineages, have drawn a new picture of the ancestry of animals. The nature of the early diverging animal lineages and the timing of the transition are in a state of flux. Various factors have been linked to this striking transition to multicellularity, including changes in environmental conditions and the ecological interactions between unicellular eukaryotes. The current wealth of genomic data has also shed new light on this question. The analysis of the genome of various close relatives of animals has revealed the importance that recycling of ancient genes into metazoan biological functions played into animal origins. A recent study reconstructing the genome of the last common ancestor of extant animals has unveiled an unprecedented emergence of new genes, highlighting the role of genomic novelty in the origin of metazoans.
什么是动物？为了找到答案，我们需要整合来自系统发育学、古生物学、生态学、发育学、解剖学、生理学以及分子生物学和基因组学等学科的数据。了解哪些类群在动物起源之前和之后分支出来至关重要。分子系统发育学的最新进展，以及新真核生物谱系的发现，描绘出了动物祖先的新图景。早期分化的动物谱系的性质以及转变的时间仍在不断变化。各种因素与向多细胞性的这一显著转变有关，包括环境条件的变化以及单细胞真核生物之间的生态相互作用。当前丰富的基因组数据也为这个问题带来了新的启示。对动物各种近亲基因组的分析揭示了古代基因循环进入后生动物生物学功能在动物起源中所起的重要作用。最近一项重建现存动物最后共同祖先基因组的研究揭示了新基因前所未有的出现，突出了基因组新奇性在后生动物起源中的作用。
