一项发表于《Science Advances》的突破性研究，由德国 Heinrich Heine University Düsseldorf 的演化生物学家 Bill Martin 及其同事主导，挑战了关于约四十亿年前地球生命起源的长期假设。自 Charles Darwin 于1871年首次对此问题进行推测以来，科学家们一直在争论各种竞争理论，然而至今尚未出现明确答案。研究人员认为，这种持续的难以捉摸，可能源于我们从一开始就提出了错误的问题。

该研究提出证据表明，生命可能实际上起源了两次，Darwin「生命树」中最早的两个谱系是从一个共同来源独立产生的。这个来源被称为「最后共同祖先」（last universal common ancestor, LUCA），传统上被视为一种原始生物体——一个原始的类细菌细胞，地球上所有生命皆由此衍生。然而，Martin 及其同事认为，LUCA 本身并非一个真正的生物实体，从而模糊了「生命」与「非生命」之间的界线。

这一概念重构对生物学和生命起源研究具有深远意义。研究结果暗示，生命并非在某个清晰的单一时刻从非生命化学转变为生物学，而是经历了一个更为模糊、渐进的过程，其中两个不同的生物谱系各自独立地从前生命化学跨越门槛进入生命系统。若获得证实，这一框架将从根本上重塑我们对生命如何诞生的理解，表明从地球化学到生物学的转变可能是透过平行路径发生，而非单一的普遍事件。

A groundbreaking study published in Science Advances by evolutionary biologist Bill Martin of Heinrich Heine University Düsseldorf and his colleagues challenges longstanding assumptions about life's origins on Earth approximately four billion years ago. Since Charles Darwin first speculated on the question in 1871, scientists have debated competing theories, yet no definitive answer has emerged. The researchers suggest this persistent elusiveness may stem from asking the wrong question entirely.

The study presents evidence that life may have effectively begun twice, with the two earliest lineages of Darwin's "tree of life" arising independently from a single common source. This source, known as the last universal common ancestor (LUCA), has traditionally been regarded as an ur-organism—a primitive bacterium-like cell from which all life on Earth descended. However, Martin and his colleagues argue that LUCA was not itself a truly biological entity, blurring the boundary between "life" and "non-life."

This reconceptualization carries profound implications for biology and origin-of-life research. Rather than a single, clear moment when non-living chemistry transitioned into biology, the findings hint at a hazier, more gradual process in which two distinct biological lineages independently crossed the threshold from pre-life chemistry into living systems. If confirmed, this framework would fundamentally reshape our understanding of how life emerged, suggesting that the transition from geochemistry to biology may have occurred through parallel pathways rather than a single universal event.