The tractable history of life records a successive emergence of organisms composed of greater numbers of hierarchically-organized objects: groups of polymers compose cells; groups of individual cells compose unicellular populations or multicellular individuals; groups of populations compose ecosystems. This repeated patterning extends up to the global biosphere, which is composed of groups of biomes. At each of these levels, the relationships between and among objects give rise to emergent features that function according to specific rules of organization. How far back into life’s evolutionary history do the formalisms of such relationships extend? Perhaps most intriguingly, one may ask: are the evolutionary relationships of life templated upon organizational attributes embedded within life’s non-biological, prebiotic roots? If so, the non-biological organizational attributes of the prebiotic realm may have been as complex as, or even more complex than, life itself. This possibility would seem to stand directly at odds with the idea that life, as a holistic phenomenon, has exhibited a steady process of complexification throughout its entire history.

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While it is undeniable that some specific clades demonstrate a history of increasing organismal complexity over time, it is also the case that:

• predicting which clades will increase in complexity in the future is not currently possible, and may be impossible due to the role of chance in evolution;

• many clades do not increase (and in some aspects may decrease) in complexity through the process of evolution;

• many factors that enable the continued existence of a population are external to those organisms, residing either within its network of relationships to their ecological cohabitants or to relationships with their non-biological (chemical) environment;

• some attributes of a changing non-biological system (e.g., planet formation and climate) exhibit prominent roles for chance and contingency, as does the evolution of life.