You claim that the identification of a 160,000-year-old Denisovan jawbone from its proteins alone is a first for palaeoproteomics (Nature 570, 433–436; 2019). This is not entirely true.

Jerold Lowenstein pioneered the detection and identification of proteins by immunological methods in fossils of hominins (a 0.5-million-year-old Homo erectus and a 1.9-million-year-old Australopithecus robustus) and other animal species (J. M. Lowenstein Phil. Trans. R. Soc. Lond. B 292, 143–149 (1981); see also C. Borja et al. Am. J. Phys. Anthropol. 103, 433–441; 1997).

Those immunological techniques relied on protein-binding information and so were less precise than mass spectrometry, which can directly provide the amino-acid sequence of fossil proteins such as collagen from the Denisovan mandible. Nevertheless, they were an important milestone in the history of molecular methods used to identify hominin fossils.