Restriction lift date: 2025-10-31
The taphonomy of feathers
Slater, Tiffany S.
University College Cork
Fossil feathers harbour key information for understanding the evolution of feathers through deep time. The ability of fossil feathers to inform on the biochemical evolution of feathers is, however, restricted due to an incomplete understanding of feather taphonomy. Accurate interpretation of data from fossil feathers requires a comprehensive understanding of the fate of key feather components – melanosomes, melanins and feather corneous beta proteins (CBPs) – during fossilization, but this is not fully characterized. Further, whether the preservation of different feather components is inter-dependent, and whether certain components impact preservation of others, is unknown. Unsurprisingly, reports of preserved feather chemistry in fossils are controversial. This thesis addresses these issues using taphonomic experiments incorporating decay, sulfurisation, oxidation, thermal maturation and high temperature-high pressure maturation on black, white and orange feathers from extant birds. The results resolve the controls on the preservation of melanosomes and melanins (in decreasing order of importance: oxidation, maturation and decay) and the proteinaceous component of feathers (in decreasing order of importance: maturation, oxidation and decay). The experimental results also support new fossil evidence for the preservation of disulfides and amides, which are indicative of feather CBPs, in Mesozoic fossil feathers and the preservation of phaeomelanin molecular residues in Miocene fossil frogs. Collectively, the results form the basis for a new integrated model for feather preservation that is firmly grounded in quantitative empirical data and encompasses all major feather components. This model explains variations in the preservation of fossil feathers and represents a major advance in our understanding of the preservation of feathers and of structural proteins. Critically, the model highlights the power of combining systematic and quantitative taphonomic experiments with a holistic, whole-tissue approach, to resolve long-standing issues relating to the preservation of soft tissues in the fossil record.
Fossil , Feathers , Taphonomy , Keratin , Corneous beta proteins , Melanin , Pigmentation , Fossil colour
Slater, T. S. 2022. The taphonomy of feathers. PhD Thesis, University College Cork.