Psychedelic-Colored Insects Flew Ancient Skies
(Full color recreation of a 50-million-year-old moth; Credit for all images: Maria McNamara)
At least one moth 50 million years ago sported a yellow-green hue highlighted by blue, black and green-cyan accents, a team of researchers concludes.
The fashion forward moth, described in the latest PLoS Biology, represents the oldest known moth for which the original colors have been determined.
The discovery, made in Germany, could help scientists learn the colors of a wide variety of long-extinct creatures, including birds, fishes, and other insects, and shed light on color's function and evolution.
"We can work out what they looked like and what they used the colors for," Yale researcher Maria McNamara said in a press release.
(What the moth looks like in glycerin)
Fossils rarely preserve evidence of original color, so we've only known the Dinosaur Era and other prehistoric times in black and white, although artists have taken creative liberties in adding color to drawings.
McNamara and her team, however, have figured out a way to tease color information out of fossils. Coloration, in turn, suggests how the long-dead individuals may have behaved and communicated, since color can play a role in both of those things.
The scientists figured out the colors by using electron microscopy and other techniques to examine fossilized scales of daytime moths that lived around 50 million years ago. The moths lived at what is now the Messel oil shale pit near Frankfurt, where numerous other high-quality fossils have been unearthed.
Evidence from anatomical details preserved in the scales helped establish the structural color of the moths' forewings, which you can see in the recreation image. McNamara says that structural colors are the brightest colors in nature — purer and more intense than chemical pigments. Tissue design generates structural colors by scattering light.
(Fossil moth scale detail)
The researchers believe the ancient day moth's colors served defensive purposes by either warning off predators, or serving as camoflauge.
"The living members of this group of day-flying moths are often brightly colored, and this fossil shows that color evolved for protection in these insects at least 50 million years ago," co-author Derek Briggs said in the press release.
(Close-up of the moth scales in glycerin)
Other recent research by Briggs, who is the director of Yale's Peabody Museum of Natural History, led to the first full-color reconstruction of the plumage of a feathered dinosaur. He also worked on the prior beetle study.
When told of the hotrod prehistoric colors, Andrew Parker, a research leader at both Oxford University's Green Templeton College and The Natural History Museum, London, expressed great interest.
"This informs us that the myriad interactions involving color that we see today — the arms race between predators and prey, and the signaling to a potential mate within conspecifics — extend back through time," Parker told Discovery News.