"What we need to find now are additional specimens that show this structure, and perhaps by comparing their sizes or relative development, we might get an idea of their sex," Bell said.
It's not clear whether the comb is a feature only of E. regalis or if other duckbills might have had similar fleshy accessories. Skin associated with the head may not preserve well, meaning that other combs have vanished without a trace, Bell said. Or, they may have been overlooked. In the past, paleontologists considered skin impressions less interesting than bones, so they ignored them.
"People would actually remove and destroy the skin that's been preserved in order to get to the bones," Bell said.
Modern preparation has the potential to lead to a deeper understanding of dinosaurs, he said. "There's going to be no end of new and very surprising discoveries to come," Bell said.
The researchers report their findings today (Dec. 12) in the journal Current Biology.
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