The search for life in the Solar System hinges on data from planetary missions. Detecting biosignatures based on molecular identity, isotopic composition, or chiral excess requires measurements that current and planned missions can only partially provide. We introduce a new class of biosignatures, defined by the statistical organization of molecular assemblages and quantified using diversity metrics. Using this framework, we analyze amino-acid diversity across a dataset spanning terrestrial and extraterrestrial contexts. We find that biotic samples are consistently more diverse -- and therefore distinct -- from their sparser abiotic counterparts. This distinction also holds for fatty acids, indicating that the diversity signal reflects a fundamental biosynthetic signature. It also proves persistent under modeled space-like degradation. Relying only on relative abundances, this biogenicity assessment strategy is applicable to any molecular composition data from archived, current, and planned planetary missions. By capturing a fundamental statistical property of life's chemical organization, it may also transcend biosignatures that are contingent on Earth's evolutionary history.

翻译：在太阳系中寻找生命依赖于行星任务的数据。检测基于分子身份、同位素组成或手性过剩的生物印记，需要当前和计划中任务仅能部分提供的测量手段。我们引入了一类新的生物印记，其定义基于分子集合的统计组织，并使用多样性指标进行量化。利用这一框架，我们分析了涵盖地球及地外背景的数据集中氨基酸的多样性。我们发现，生物样本始终比其稀疏的非生物对应样本更具多样性——因而也更独特。这种区分也适用于脂肪酸，表明多样性信号反映了基本的生物合成印记。此外，在模拟的太空环境退化条件下，该信号仍具有持久性。仅依赖于相对丰度，这种生物源性评估策略可应用于来自存档、当前及未来行星任务的任何分子组成数据。通过捕捉生命化学组织的基本统计特性，它或许还能超越那些依赖于地球进化历史的生物印记。