figshare
Browse

sorry, we can't preview this file

rspb20171050_si_001.docx (504.52 kB)

Supplementary methods and figures from Preservation of uropygial gland lipids in a 48-million-year-old bird

Download (504.52 kB)
journal contribution
posted on 2017-10-09, 09:54 authored by Shane O'Reilly, Roger Summons, Gerald Mayr, Jakob Vinther
Although various kinds of organic molecules are known to occur in fossils and rocks, most soft tissue preservation in animals is attributed to melanin or porphyrins. Lipids are particularly stable over time—as diagenetically altered ‘geolipids’ or as major molecular constituents of kerogen or fossil ‘geopolymers’—and may be expected to preserve in certain vertebrate tissues. Here we analysed lipid residues from the uropygial gland of an early Eocene bird using pyrolysis gas chromatography mass spectroscopy. We found a pattern of aliphatic molecules in the fossil gland that was distinct from the host oil shale sediment matrix and from feathers of the same fossil. The fossil gland contained abundant n-alkenes, n-alkanes and alkylbenzenes with chain lengths greater than 20, as well as functionalized long chain aldehydes, ketones, alkylnitriles and alkylthiophenes that were not detected in host sediment or fossil feathers. By comparison with modern bird uropygial gland wax esters, we show that these molecular fossils are likely derived from endogenous wax ester fatty alcohols and fatty acids that survived initial decay and underwent early diagenetic geopolymerisation. These data demonstrate the high fidelity preservation of the uropygial gland waxes and showcase the resilience of lipids over geologic time and their potential role in exceptional preservation of lipid-rich tissues of macrofossils.

History

Usage metrics

    Proceedings of the Royal Society B: Biological Sciences

    Licence

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC