Summer is a time for pondering and Summer is reaching its peak in the Northern hemisphere. The extremely hot and humid weather now so pervasive in many locations might, in some bodies, feel like a hydrothermal vent. When feeling thus, some minds might ponder on the largely unknown events that happened between the Origin of Life and the Last Universal Common Ancestor, or LUCA. Mine did, yours might too. If so, I recommend some reading as a foundation for such mental wanderings.
I found a perfect starting point in a brief opinion/review by Goldman and Kaçar, "Very early evolution from the perspective of microbial ecology." I don't know about you, but I tend to imagine the very early stages of evolution involving RNA replicators within vesicles, akin to a contained and slow PCR reaction. Individual protocells in any case. This review opened my mind to the possibility that "the first lifeforms may have existed as a sort of biofilm composed of semi-cellular replicators that eventually evolved into a community of cellular organisms." The concept of a "ribofilm" as put forth by Barross and Martin. Fascinating to think of such early "protoorganisms" as large enough to be visible to the naked eye! (But, of course, no eyes to see them back then...) And that's just one of the many ideas present in this piece. Not only is the text itself thought-provoking, but its collection of references is also a treasure trove to keep exploring the topic.
Happy Summer reading!