A Field Trip to the Archaean in Search of Darwin's Warm Little Pond.
A Field Trip to the Archaean in Search of Darwin's Warm Little Pond.
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DOI：
10.3390/life6020021
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发表时间：
2016-05-25
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影响因子：
--
通讯作者：
Damer B
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作者：
Damer B
查尔斯·达尔文最初的直觉是生命起源于一个“温暖的小池塘”，但在过去的三十年里，他对海洋热液喷口作为自然发生场所的关注使这一直觉黯然失色。然而，关键分子结构单元聚合的热力学障碍和在海水中形成稳定的膜室的困难表明，应该重新考虑达尔文最初的见解。我将介绍陆地生命起源假说，它结合了实地观察和实验室结果，提供了一个新颖的和可测试的模型，其中生命开始作为原始细胞组装在内陆淡水热液领域。热液场与类似于今天的夏威夷和冰岛的火山陆地有关，并且可能存在于从地球第一个海洋中升起的类似陆地上。我将报告对西澳大利亚州的活的和古老的叠层石化石地点的实地考察，这为生命如何在西澳大利亚州的波动的淡水热液池中出现提供了关键的见解，最近发现了地质证据。实验室实验和野外工作提供了越来越多的证据，证明这些位点具有有利于聚合反应和产生膜结合的原始细胞的特性。我将建立在以前开发的耦合阶段的情况下，统一的化学和地质框架，并提出一个稳定的水凝胶，共同支持的原始细胞将成为候选人Woese progenote，微生物群落的遥远的共同祖先，在最早的化石记录中如此丰富。
Charles Darwin’s original intuition that life began in a “warm little pond” has for the last three decades been eclipsed by a focus on marine hydrothermal vents as a venue for abiogenesis. However, thermodynamic barriers to polymerization of key molecular building blocks and the difficulty of forming stable membranous compartments in seawater suggest that Darwin’s original insight should be reconsidered. I will introduce the terrestrial origin of life hypothesis, which combines field observations and laboratory results to provide a novel and testable model in which life begins as protocells assembling in inland fresh water hydrothermal fields. Hydrothermal fields are associated with volcanic landmasses resembling Hawaii and Iceland today and could plausibly have existed on similar land masses rising out of Earth’s first oceans. I will report on a field trip to the living and ancient stromatolite fossil localities of Western Australia, which provided key insights into how life may have emerged in Archaean, fluctuating fresh water hydrothermal pools, geological evidence for which has recently been discovered. Laboratory experimentation and fieldwork are providing mounting evidence that such sites have properties that are conducive to polymerization reactions and generation of membrane-bounded protocells. I will build on the previously developed coupled phases scenario, unifying the chemical and geological frameworks and proposing that a hydrogel of stable, communally supported protocells will emerge as a candidate Woese progenote, the distant common ancestor of microbial communities so abundant in the earliest fossil record.