Kuwae's work includes a detailed analysis of almost 400 geological and biological records, including lake sediments, corals and tree rings, from 137 geographical locations around the world, which allow us to infer human influence on the natural environment over the last 8,000 years. It is therefore an arduous, detailed and very complete work, which provides solid and conclusive results.

This study complements previous work of the same kind, which seeks to provide as concrete an age as possible for the beginning of the alteration of the planet's natural biogeochemical cycles due to human influence. In this way, the research team concludes the existence of three key moments in recent history: the second half of the 19th century (between 1855 and 1890), coinciding with the Industrial Revolution; the beginning of the 20th century (from 1909 to 1944); and the middle of the 20th century (between 1948 and 1953), at the start of the so-called ‘Great Acceleration’. The data provided also show that it was during the latter period, particularly from 1952 onwards, that the main alteration of natural cycles as a result of human activity began.

In this way, this work demonstrates the existence of a significant human footprint in the recent geological and biological record, making it clear that humans have been able to alter the natural behaviour of different environments on our planet since the middle of the last century. However, these results are not sufficient to establish the year 1952 as the beginning of a new subdivision of the geological time scale, the Anthropocene, since, as the International Commission on Stratigraphy (ICS) recently concluded, it is not possible to infer the future persistence, on a geological scale, of this evidence in the sedimentary record. But it is a further reminder of the importance of reducing the human effect on the planet in order to predict future climatic and biotic changes and adapt to them efficiently.

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