For decades, the search for life beyond Earth has revolved around a key question: What molecules should scientists be looking for on other planets or moons? A new study, published in Nature Astronomy, suggests that the more revealing clue may not be the molecules themselves, but the hidden order connecting them.

“We’re showing that life does not only produce molecules,” said Fabian Klenner, UC Riverside assistant professor of planetary sciences and co-author of the study. “Life also produces an organizational principle that we can see by applying statistics.”

The researchers found that amino acids are consistently more diverse and more evenly distributed in a material sample created by a living thing than those found in abiotic or nonliving things. In contrast, the pattern reverses for fatty acids: Abiotically produced fatty acids are distributed more evenly than those produced by biological processes.