Over 4,400 human brains have been unearthed by archaeologists, and 600 putative animal brains have been identified in fossils up to half a billion years old. As metabolically active cells, neurons readily degrade by autolysis (the digestion of a cell by its own enzymes) and decay experiments suggest that brains are amongst the first organs to decompose postmortem; yet the richest complex of preserved biomolecules from any ancient material constitutes that of an Iron Age human brain (Petzold et al. 2020). Biomolecules like proteins, lipids and metabolites are a valuable bioarchive of past life, and ancient nervous tissues provide unique insights into the palaeobiology of extinct taxa, such as the development of chemical and electrical signalling systems during the early radiation of metazoa. However, given <1% of brains excavated have been investigated at the molecular level, their nature remains controversial.
I'm fascinated by exceptional soft tissue preservation in the fossil record; and as a molecular taphonomist I study the degradation of biomolecules in deep time, and their interactions with metals and minerals. My doctoral research at Oxford has assembled the world’s largest collection of ancient nervous tissues, applying complementary multi-omic and mineralogical approaches with the aim to understand the molecular mechanisms underpinning fossilisation of the central nervous system. Understanding these mechanisms has exciting palaeobiological implications not only for deepening our knowledge of extant fossils, but for targeting our search for new fossil sites worldwide.
