Microraptor’s feathers fully revealed by UV light

I don’t have much time for an involved post but it would be remiss of me not to mention that my friend and supporter of Dracovenator, Dave Hone, has a new paper out in PLOS One. Dave and several of his colleagues have been looking at famous Liaoning fossils under UV light in order to see what structures may become visible that you can’t see under ordinary white light. The technique has been used to great effect by Helmut Tischlinger (one of the authors on the present paper) on pterosaurs from Solnhofen, revealing all sorts of structures like soft tissue crests, and keratinous beak-tipped jaws.

The present paper answers a very specific question. A halo of non-preservation seems to occur between the skeletons and the feathery plumage of feathered theropods from Liaoning. Is this halo real or just a preservational artefact? Hone et al. looked at one of these theropods, Microraptor, and decisively found that it is indeed a preservational artefact. Under UV light the feathers in the halo region show up nice and clearly, the rachis (‘stem’) of large flight feathers making a connection with their supporting bones, just as in modern birds. This means that a) the flight feathers, even those of the hind wing, were rooted firmly to the skeleton and b) were longer than we had previously realised. If you want to read more check out Dave’s own blog posts here and here. Otherwise download the paper itself – its free.

Figure 1. There be  feathers in them thar halos. The feathers of Microraptor gui (white arrows), and the apparently unfeathered halo (black arrows). Image from Hone et al. 2010.