Plenarist Abstracts

The debt of biological and human evolution to geology

Telmo Pievani

Charles Darwin wanted to be remembered as a geologist, not only because he was grateful for the discovery of Deep Time, but also because geology was his epistemological model of rigorous natural science, capable of identifying patterns of change. Charles Lyell's uniformitarianism led him to an excessively gradualist view of evolution, but contemporary corrections to this idea also owe everything to geology: punctuated speciations; turnover pulses; mass-extinctions. These macroevolutionary and geological factors are essential to understanding human evolution as well: from the initial formation of the Rift Valley in Africa (which initiated the diversification of hominins like us) to the climatic oscillations of the Pleistocene and the resulting migrations of hominins out of Africa. The phylogenetic tree of the genus Homo has been shaped by large-scale geological factors. This natural history makes it somewhat ironic that today Homo sapiens, the product of a history of large-scale geological and ecological perturbations, has itself become a geological force capable of altering the fundamental geophysical cycles of the planet.

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