Survival of mineral-bound peptides into the Miocene

Peer reviewed: True
Funder: Alexander von Humboldt Foundation; FundRef: http://dx.doi.org/10.13039/100005156
Funder: University of Texas at Austin; FundRef: http://dx.doi.org/10.13039/100008562
Funder: National Natural Science Foundation of China; FundRef: http://dx.doi.org/10.13039/501100001809
Previously, we showed that authentic peptide sequences could be obtained from 3.8-Ma-old ostrich eggshell (OES) from the site of Laetoli, Tanzania (Demarchi et al., 2016). Here, we show that the same sequences survive in a >6.5 Ma OES recovered from a palaeosteppe setting in northwestern China. The eggshell is thicker than those observed in extant species and consistent with the Liushu Struthio sp. ootaxon. These findings push the preservation of ancient proteins back to the Miocene and highlight their potential for paleontology, paleoecology, and evolutionary biology.