Table 1_Integrating radiocarbon and stable isotopes in odontocete teeth to reveal life histories.xlsx

In contrast, radiocarbon values in another killer whale indicate a mismatch between GLG counts and elapsed time, with 52 visible GLGs but F¹⁴C values consistent with a substantially older age, potentially 65+ years. A further individual exhibits consistently elevated radiocarbon values, with F¹⁴C approximately 1.11–1.13, linked to nuclear reprocessing-derived inputs, indicating long-term foraging within the west of Scotland marine environment.

In sperm whale teeth, δ¹³C values ranged from approximately −14.0‰ to −11.7‰ and δ¹⁵N values from 11.3‰ to 17.1‰, with both individuals showing decreasing δ¹³C and increasing δ¹⁵N through the tooth record. In killer whales, δ¹³C values ranged from approximately −15.4‰ to −12.4‰ and δ¹⁵N values from 12.4‰ to 19.2‰, with distinct individual isotopic ranges indicating divergent ecological histories.

These results demonstrate that odontocete teeth preserve temporally structured ecological records, but that GLG-based chronologies may lose fidelity in older individuals, highlighting the value of integrating radiocarbon validation with isotope analyses.</p>