IDEA2

Isotopic signals in dental tissues and inner ear bone: methodological advancements and applications

01/03/2023 to 28/02/2025

Stable isotope analysis of bones and teeth is a powerful tool for the study of past dietary habits, food web dynamics, and ecology. Food deprivation can also alter the isotope signals, and its identification can have important implications for the relevant fields. Currently, no study has examined whether any sub-annual variations in the bulk and amino acid isotope composition of teeth and petrous bone (in utero/infancy signal) can be linked to starvation in animals a) experiencing different herd management practices, or b) living in extreme winter conditions. Hominins may have survived harsh winters by hibernating, a physiological adaptation to anticipated starvation. To date, no study has assessed whether hibernation affects the bulk and amino acid isotope values of teeth and petrous bones in extinct bears, a highly efficient hibernator that can be used as an analogue for hominins.
The enamel δ13C biogenic signals can be retained in geological timescales, however recovering original δ13C and δ15N signals from bone and dentine collagen of fossils and archaeological remains from environments not favouring organic preservation is extremely unlikely. The tooth enamel δ15N can help unlock the secrets of physiology-related changes as the enamel proteins can survive for millions of years. At present, we have no insight on a) the relationship between the enamel, dentine and petrous bone δ15N, and b) the preservation potential of the enamel δ15N in archaeological and fossil teeth, that would promote its application in the relevant research fields.
This project will provide: a) the first fine-scale correlation between the enamel, dentine and petrous bone δ15N; b) an assessment of the enamel δ15N preservation in archaeological and palaeontological material; c) a novel investigation of starvation isotopic indicators in animals living in extreme winter conditions and castrated sheep; and d) a pioneering isotopic study for the detection of hibernation signals in extinct bears.