The University of Queensland, Institute for Molecular Bioscience, St Lucia, Brisbane, Queensland, Australia.
Biol Direct. 2009 Nov 16;4:43; discussion 43. doi: 10.1186/1745-6150-4-43.
It is well-known that Charles Darwin sketched abstract trees of relationship in his 1837 notebook, and depicted a tree in the Origin of Species (1859). Here I attempt to place Darwin's trees in historical context. By the mid-Eighteenth century the Great Chain of Being was increasingly seen to be an inadequate description of order in nature, and by about 1780 it had been largely abandoned without a satisfactory alternative having been agreed upon. In 1750 Donati described aquatic and terrestrial organisms as forming a network, and a few years later Buffon depicted a network of genealogical relationships among breeds of dogs. In 1764 Bonnet asked whether the Chain might actually branch at certain points, and in 1766 Pallas proposed that the gradations among organisms resemble a tree with a compound trunk, perhaps not unlike the tree of animal life later depicted by Eichwald. Other trees were presented by Augier in 1801 and by Lamarck in 1809 and 1815, the latter two assuming a transmutation of species over time. Elaborate networks of affinities among plants and among animals were depicted in the late Eighteenth and very early Nineteenth centuries. In the two decades immediately prior to 1837, so-called affinities and/or analogies among organisms were represented by diverse geometric figures. Series of plant and animal fossils in successive geological strata were represented as trees in a popular textbook from 1840, while in 1858 Bronn presented a system of animals, as evidenced by the fossil record, in a form of a tree. Darwin's 1859 tree and its subsequent elaborations by Haeckel came to be accepted in many but not all areas of biological sciences, while network diagrams were used in others. Beginning in the early 1960s trees were inferred from protein and nucleic acid sequences, but networks were re-introduced in the mid-1990s to represent lateral genetic transfer, increasingly regarded as a fundamental mode of evolution at least for bacteria and archaea. In historical context, then, the Network of Life preceded the Tree of Life and might again supersede it.
众所周知，查尔斯·达尔文在 1837 年的笔记本中绘制了抽象的关系树，并在《物种起源》（1859 年）中描绘了一棵树。在这里，我试图将达尔文的树放在历史背景中。到 18 世纪中叶，“伟大的存在之链”越来越被认为是对自然界秩序的一种不充分描述，到 1780 年左右，它在没有达成令人满意的替代方案的情况下被基本放弃。1750 年，多纳蒂将水生生物和陆生生物描述为形成一个网络，几年后，布丰描绘了一个犬种的谱系关系网络。1764 年，邦尼特问链条是否可能在某些点分支，1766 年，帕拉斯提出生物之间的渐变类似于一棵具有复合树干的树，也许与后来埃希瓦尔德描绘的动物生命之树不同。1801 年奥吉尔提出了另一棵树，1809 年和 1815 年拉马克提出了两棵树，后两者假设物种随时间发生了变化。18 世纪后期和 19 世纪初期，植物和动物之间的亲缘关系的详细网络被描绘出来。在 1837 年前的二十年里，生物之间所谓的亲缘关系和/或类比被各种几何图形所代表。1840 年，一本流行教科书中用树来表示连续地质层中的植物和动物化石系列，而 1858 年，布朗恩用树的形式展示了化石记录所证明的动物系统。达尔文 1859 年的树及其随后由海克尔的阐述在许多但不是所有生物学领域得到了接受，而网络图则在其他领域得到了应用。从 20 世纪 60 年代初开始，从蛋白质和核酸序列中推断出树，但在 20 世纪 90 年代中期又重新引入了网络来表示侧向基因转移，侧向基因转移越来越被认为是一种基本的进化模式，至少对细菌和古菌而言。从历史背景来看，生命之网先于生命之树，而且可能再次取代它。
