, Volume 90, Issue 12, pp 563–567 | Cite as

The dinosaurian origin of feathers: perspectives from dolphin (Cetacea) collagen fibers

  • Theagarten Lingham-SoliarEmail author
Short Communication


The early origin of birds is a hotly disputed debate and may be broadly framed as a conflict between paleontologists and ornithologists. The paleontological emphasis has shifted from Archaeopteryx and its origins to recent finds of Cretaceous birds and “feathered” dinosaurs from China. The identification of alleged feathers has, however, relied principally on the visual image. Some workers have interpreted these integumentary structures as collagen fibers. To test the latter hypothesis, using light microscopy, collagen from the hypodermis (blubber) and subdermal connective tissue sheath was examined from a dolphin that had been buried for a year as part of an experiment. Within the blubber, toward the central thicker parts of the material, the collagen fibers had compacted and the three-dimensional latticework of normal blubber had more or less collapsed. Chromatographic analysis of the blubber revealed pronounced oxidation of the unsaturated lipids, probably accounting for the collapse of the latticework. Fibers normally bound together in bundles became separated into individual fibers or smaller bundles by degradation of the glue-like substance binding them together. These degraded collagen fibers show, in many instances, feather-like patterns, strikingly reminiscent of many of those identified as either “protofeathers” or “modern” feathers in dromaeosaurid dinosaurs. The findings throw serious doubt on the virtually complete reliance on visual image by supporters of the feathered dinosaur thesis and emphasize the need for more rigorous methods of identification using modern feathers as a frame of reference. Since collagen is the main fiber type found in most supporting tissues, the results have wide implications regarding the degradation and fossilization of vertebrate integument, such as that of the ichthyosaurs, dinosaurs and birds.


Bottlenose Dolphin White Shark Loggerhead Turtle Tiger Shark Collagen Fiber Bundle 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Thanks to G. Cliff (Natal Sharks Board) for provision of the dolphin and shark specimens. I am especially grateful to Prof. O. Grahl-Nielsen (Bergen University, Norway) for lipid analysis and discussions on the decomposing dolphin blubber and to H. Axer (Institute for Anatomy, Aachen, Germany) for discussions on collagen. Finally, I am grateful for the three (anonymous) constructive reviews.


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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  1. 1.Zoology DepartmentUniversity of Durban-WestvilleDurbanSouth Africa

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