Lead is a well known pollutant affecting human health over the course of our urbanisation and industrialisation. But what about before this? Analysis of a range of fossil hominid teeth from the Pleistocene reveals that lead poisoning might have been a ubiquitious part of our deep evolutionary history. Furthermore, lab experiments looking at the effect of lead exposure on human and neanderthal brain development reveals the interplay between this pollutant and 'the language gene' (FOXP2). Together, this suggests that the development of language, socialisation and ultimate evolutionary success of humans might be related to our ability to overcome lead poisoning.

This week's paper is "Impact of intermittent lead exposure on hominid brain evolution" by Renaud Joannes-Boyau and colleagues published in Science Advances, October 2025. https://doi.org/10.1126/sciadv.adr1524

Wide screen art by Mark Witton