A new approach in deciphering early protist paleobiology and evolution: Combined microscopy and microchemistry of single Proterozoic acritarchs

Beside a few cases, the biological affinities of Proterozoic and Paleozoic acritarchs remain, by definition, largely unknown. However, these fossils record crucial steps in the early evolution of microorganisms and diversification of complex ecosystems.We present how combining microscopy (light microscopy, scanning and transmitted electron microscopy) with microchemical analyses of individual microfossils may offer further insights into the paleobiology and evolution of early microorganisms. We use our ongoing work on early Mesoproterozoic and Neoproterozoic assemblages, as well as other published work, as examples to illustrate how this approach may clarify the evolution of early microorganisms and we underline how useful this approach could be for palynologists working on younger material. Such a multidisciplinary approach offers new possibilities to investigate the biological affinities of acritarchs and the record of early life on Earth and beyond.