Investigating the fossil record of early noncalcified macroalgae: progress, possibilities, and pitfalls

Abstract Knowledge of the evolutionary history of life has increased markedly during the past 100 years, but over the last 30 years gains in the basic outlines for early macroalgae have been especially great, driven in large part by the discovery of many new macroalga-bearing Lagerstätten in Proterozoic and lower Paleozoic strata, particularly in China. Nonetheless, much remains to be done, and achieving a greater level of understanding of early macroalgae in the fossil record is essential to increasing understanding of significant Earth system change during the Proterozoic and early Paleozoic, including several major evolutionary radiations of animals. This paper examines recent advances in this field of study in terms of identification methods, modes of preservation, depositional/stratigraphic context, and broad-scale ecological and evolutionary history, and topics are highlighted that show particular promise for future work. In addition, ever-present pitfalls are illuminated together with suggested pathways around them.