Could ecological roles offer clues to how life began?

Producers, consumers, and decomposers each contribute unique roles within modern ecosystems. This article suggests that investigating these familiar roles may provide valuable insights into how life initially emerged. By examining the organization of ecosystems, it connects with the researcher's broader studies on soil colloids, biological membranes, radiation-induced reactions, and environmental trace substance movement.

The researcher explores whether differences in environmental structures could have given rise to distinct chemical functions in early life. Hydrothermal vents are considered potential candidates, as interactions between water and rock can provide chemical energy, reactive minerals, and conducive conditions for organic synthesis. Pores in these vents might also concentrate molecules, while cooler mixing zones offer alternative environments compared to the hot vent fluids.

The researcher investigates how these varied conditions impact the fate of reaction products. They highlight that making a useful molecule is only the first step, with retaining it available for subsequent reactions being equally important. Breakdown of compounds could aid chemical reuse if smaller, reusable products are formed. Hydrothermal systems may therefore support synthesis, transformation, and recycling, depending on local conditions.

Ice-water interfaces present another set of possibilities. When water freezes, certain substances become concentrated in the remaining liquid, creating small, liquid regions where reactants can come together. Experiments have shown that RNA building blocks can join into longer chains when supplied with chemicals. Furthermore, RNA catalysts can function within liquid regions within ice.

However, these results do not demonstrate that ice spontaneously produces RNA from simple ingredients, and thawing can dilute or remove products.

The researcher proposes examining whether these settings can retain useful compounds long enough for further chemistry, including reactions after transfer elsewhere. They use producer-like, consumer-like, and decomposer-like functions as analogies to describe possible chemical processes. These terms describe potential chemical functions but do not establish metabolism, biological consumption, or an ecosystem prior to cellular life.

The researcher introduces the concept of environmental structural ecology, which examines how the arrangement and connections of reaction environments influence chemical activity. They suggest that connections are only useful if molecules survive the transfer, emphasizing the need to consider factors such as dilution, destructive conditions, and incompatibility with chemistry.

To explore these possibilities, the researcher advocates for comparing connected reactors with isolated reactors receiving equivalent amounts of feedstock and energy. One reactor could offer conditions for concentration and retention, while the other supports chemical transformation. By tracking specific compounds through both stages, researchers could determine if transferred molecules survive, enter subsequent products, and if coupling the environments sustains reaction activity better than keeping them separate.

Evidence of recycling should demonstrate reuse, rather than merely finding smaller fragments after breakdown. Additionally, any advantages of coupling would need to be distinguished from the effects of concentration, dilution, or reaction time. The article presents a conceptual framework rather than new experimental validation, focusing on the question of whether environmental differences helped shape the emergence of biological roles.