Scientists have discovered a fleshy comb on top of a mummified duck-billed Edmontosauraus regalis' head, marking the first evidence for "bizarre soft-tissue display structures among dinosaurs."

"These findings dramatically alter our perception of the appearance and behavior of this well-known dinosaur and allow us to comment on the evolution of head crests in this group," says Phil Bell from Australia's University of New England. "It also raises the thought-provoking possibility of similar crests among other dinosaurs."

The comb is similar to a rooster's crest. The rare, intact Edmontosauraus regalis specimen was unearthed west of the city of Grande Prairie in west-central Alberta, Canada. The group of researchers involved theorizes that the comb was probably used for mating purposes and for establishing roles in the herd.

The duck-billed dinosaur was once the most common dinosaur in North America between 65 and 75 million years ago and played a role similar to deer. Despite their large numbers, finding evidence of a soft-tissue display structure on a duck-billed dinosaur is exciting for the scientists because such biological components usually don't stand the test of time.

"This is equivalent to discovering for the first time that elephants had trunks," Bell said. "We have lots of skulls of Edmontosaurus, but there are no clues on them that suggest they might have had a big fleshy crest. There's no reason that other strange fleshy structures couldn't have been present on a whole range of other dinosaurs, including T. rex or Triceratops."

You can read the full published study detailing the findings in the journal Current Biology.