99-Million-Year-Old Insects Caught in Amber Shows Brilliant Colors

Colors are everywhere in nature, from the radiant sunshine or the colorful feathers of the peacock to the pearl white camouflage of polar bears. But when thinking of the color scheme sported by the prehistoric world, the first thing that'd come to mind would be full of greens and browns.

Normally, fine structural detail needed for the conservation of color is rarely preserved in the fossil record. That is why most reconstructions of the fossil depend upon the imagination of the artist.

But more research has shown that millions of years ago, colors of nature are typically similar to the colors of today. The latest evidence of that is from the study of the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS) which discovered the true coloration in 99-million-year-old insects.

Structural Colors of Insects Preserved in Amber

Knowing the colors of prehistoric creatures is a challenging task, especially when what's left of them, such as bones, cannot convey what color they were when they were still living.

But scientists have recently been working out pigments from fossilized feathers or in the case of the most recent study, used Burmese amber to see the world of ancient colors.

Pan Yanhoong, a paleontologist from the Chinese Academy of Science, explained that the structural color is the type of color preserved in amber fossils which are caused by microscopic structure os the animal's surface.

"The surface nanostructure scatters light of specific wavelengths and produces very intense colors. This mechanism is responsible for many of the colors we know from our everyday lives," says Yanhoong.

Moreover, structural color is what makes the color of the peacock feathers and butterfly scales appear iridescent. But in the case of the preserved insect, it was created by the outer cuticle of the exoskeleton of the insect.

Altered Coloration Among Fossilized Insects

The researchers collected 35 amber specimens with ancient insects that also have these intense, incredible structural colors. Most of the specimens were either of the cuckoo wasps (family Chrysididae) or chalcid wasps (from the superfamily Chalcidoidea). Even inside the amber, these insects sport their metallic bluish-green, yellowish-green, purplish-blue, or even vibrant green bodies, according to Science Alert. They find a striking resemblance of cuckoo wasps in amber to the cuckoo wasps that are around today. It showed almost the same color. According to the researchers, the color displayed by the fossils are often misleading because fine nanostructures responsible for coloration can be changed during fossilization. But the original color of the fossils can still be reconstructed through theoretical modelling. "The calculated reflectance peaks match the observed metallic bluish-green coloration of the mesopleuron of our studied wasp, confirming that extremely fine nanostructures can be preserved in Mesozoic amber," the researchers noted.

Only Some of the Amber Fossils Retained Their Color

In their research published in Proceedings of the Royal Society B: Biological Sciences, the team explained why only some amber insect fossils retained their color.

They cut through the exoskeleton of two of the vibrant wasps and one dull fossil. They found that the dull sample's cuticular structures are damaged, while the colorful fossils' exoskeletons and nanostructures that scatter light were still preserved.

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