Fig. 3: Fundamental trade-offs in phototrophic machinery dictate ecological interactions and evolutionary trajectories.
From: Priority effects inhibit the repeated evolution of phototrophy
A Optimal chlorophototrophs maximize light efficiency in low light while optimal retinalphototrophs excel in high light. B This specialization persists when examining energy flux per unit protein, with each system showing superior flux in the same light conditions. C Trade-off between light efficiency and protein efficiency across all light intensities. Each system creates a Pareto front showing the maximum achievable efficiency combinations. The crossing curves demonstrate that chlorophototrophs dominate in some conditions (solid green) while retinalphototrophs dominate in others (solid purple), with non-competitive regions shown as dotted lines. D Evolutionary model showing priority effects in photosynthetic diversification. Modern chlorophototrophs (dark green) and retinalphototrophs (dark purple) occupy optimal positions along their respective Pareto fronts. Early, less efficient ancestors (light circles) rapidly evolved toward these optimal curves and diverged into distinct ecologies (arrows). These established systems now prevent evolution of competing pathways (red crosses) because new systems would be initially less efficient and quickly outcompeted.
