It’s pretty much an established fact that insects are among the world’s most diverse groups of animals. With a plethora of species of critters that live in nearly all hospitable environments across the globe, it’s no secret that these animals know a thing or two about standing out amongst a crowd. Some of the most famous insects are known precisely for their distinct, beautiful patterns on their bodies. It also comes as no surprise that these animals have been to nearly all parts of the world—they’ve been around for at least 400 million years. What isn’t immediately clear, though, is if insects had always carried such colorful patterns in their bodies. Clear, distinct patterns in such body features are a rare sight in insect fossils, after all.
Fossilization, though strikingly beautiful at first glance, is very much a game of chance—and the odds are stacked pretty much against the organism in question. Any fossil-to-be must possess parts that are sturdy enough to withstand the stresses induced by the fossilization process, and must be at just the right place at just the right time for fossilization to occur. (Say, for example, an organism may quickly become buried in sediment, locking it in place and preventing the usual decomposition process from taking place after its death.) That’s not even considering the natural forces and the elements at work around the fossilizing body; it must somehow escape floods, earthquakes, landslides, and other forms of land-altering events pretty much unscathed for the specimen to survive the millions of years between when it died and when modern-day human paleontologists start scurrying about looking for funny-looking rocks. And lest you forget: the scientists have to find the fossil first.
With all those factors in play, it’s pretty rare to find pristine fossils of animals—especially with patterns intact. While the fossilization process does allow for some patterns and body features to remain as fossil impressions, what scientists often find are incomplete, distorted, or sometimes outright missing. It’s all these odds stacked against a fossil that, when grouped together, make this startling 49 million-year-old beetle fossil discovery from the Denver Museum of Nature and Science, published in the journal Papers in Palaeontology, all the more striking.
Scientists had actually already found this fossil before, all the way back in 1995, from the Green River Formation fossil deposits—a group of ancient Eocene-epoch lakebeds spanning Colorado, Wyoming, and Utah, in the United States. It had originally been classified as a long-horned beetle, from the genus Cerambycidae. After a second glance, however, Dr. Frank-Thorsten Krell, the museum’s senior curator of entomology and lead author of the study in question, started to question whether the beautiful beetle fossil might belong to a different group of beetles after all.
With the fossil’s distinct short and stout hind legs, the researchers reassigned the beetle to another group of insects. As the curator of Luxembourg’s National Museum of Natural History and study co-author Dr. Francesco Vitali put it: “We looked at all the preserved details. It was the beetle’s crooked legs—its curved hind tibiae—that gave away its true identity: a frog-legged leaf beetle.”
The beetle now belongs to the beetle family Sagrinae, and now possesses a different scientific name: Pulchritudo attenboroughi, or “Attenborough’s Beauty.” When discovering a new species of animal, fossilized or otherwise, scientists get the chance to name the said new animal, and they often pull inspiration from all sorts of places; in this case, Dr. Krell immediately thought of one of his personal heroes: Sir David Attenborough, English naturalist and broadcaster. Attenborough is perhaps most famous the world over for his nature documentary work; Dr. Krell immediately thought of the naturalist because of the role he played in inspiring him, his family, and millions of other people across the world. According to Dr. Krell: “Nobody imparts the grandeur and beauty of nature more impressively than Sir David. This fossil, unique in its preservation and beauty, is an apt specimen to honor such a great man.” (Attenborough is also a well-known fan of collecting fossils; he has been doing so since his childhood.)
As of now, it remains unclear as to how exactly a 49 million-year-old beetle fossil retained so much of its patterns in life with such startling contrast and clarity. It is hypothesized that the animal must have died then sunk down to the lakebed, an area likely to contain fine particles such as silt or clay. According to Dr. Krell, the fine particles on the lakebed must have played a major role in allowing such pristine fossilization; after all, the beetle needed to have been compressed beneath sediment without decomposing, so an oxygen-poor lakebed is precisely the environment it needed to fossilize so well. How these clay or silt particles managed to retain the patterns on its body and wings with such clarity, however, remains a target for further study.
Bibliography
- Bressan, D. (2021`, August 7). 49-Million-Year-Old ‘Beautiful Beetle’ Named After Sir David F. Attenborough. Forbes. Retrieved September 3, 2021, from https://www.forbes.com/sites/davidbressan/2021/08/07/49-million-year-old-beautiful-beetle-named-after-sir-david-f-attenborough/
- Sci-News.com. (2021, August 10). Paleontologists Find Frog-Legged Beetle Fossil in Colorado. Sci-News.com. Retrieved September 3, 2021, from http://www.sci-news.com/paleontology/pulchritudo-attenboroughi-09944.html
- Weisberger, M. (2021, August 15). 49 million-year-old beetle looks like it was squashed yesterday. LiveScience. Retrieved September 3, 2021, from https://www.livescience.com/attenborough-beauty-beetle-fossil.html
- Krell, F. T., & Vitali, F. (2021). Attenborough’s beauty: exceptional pattern preservation in a frog‐legged leaf beetle from the Eocene Green River Formation, Colorado (Coleoptera, Chrysomelidae, Sagrinae). Papers in Palaeontology.