For the first time, scientists have uncovered a large amber deposit in South America containing fossilized insects and other preserved creatures. The small, half-transparent fossils hold a rich assortment of ancient bugs—and a slice of life from little-known ecosystems from over 100 million years ago.
A Communications & Earth Environment study published today details amber samples from Ecuador’s Genoveva quarry—the first discovery in South America to yield fossilized insects and other life forms. The team, led by paleobiologist Xavier Delclòs from the University of Barcelona in Spain, employed a multidisciplinary approach to analyze the fossils in fine detail. Their efforts unveiled the prior existence of a vibrant, tropical rainforest as the Earth underwent major environmental shifts.
“It is the largest Cretaceous amber deposit ever found in the Southern Hemisphere—and in terms of volume, it even surpasses the richest deposits of the North,” Delclòs told Gizmodo.
Indeed, the sheer volume of the deposits gave the team a rare opportunity to study and identify about 21 bio-inclusions, or living things that get stuck in amber. The discovery “opens a new window into the forests of South America at the time of the dinosaurs, preserving creatures so small and delicate that they almost never fossilize,” Delclòs said.
Preserved in amber
Amber is fossilized resin, also known as tree sap. Resin remains sticky for a couple of days to several months, trapping the occasional insect or organism that stumbles across its path. Eventually, exposure to the air hardens the resin, fastening the molecular bonds within and turning it to hard amber—along with whatever poor creature was stuck inside.
Paleontological records indicate that trees have produced resin for over 320 million years, but it’s only been within the last 120 million years that amber has “formed in large enough quantities” to create sizable fossil deposits, Delclòs explained. While amber can preserve smaller animals less likely to fossilize, the long process quickly decomposes bodily parts weaker than the exoskeleton of arthropods.
Of course, nature sometimes works miracles, and some amber deposits keep muscles, organs, and even brains intact. The new discovery, for instance, found fragile, thin strands of spider silk. The team also discovered some of the oldest flowering plants ever found in western South America. That said, DNA molecules are the fastest to go, so “the Jurassic Park dream remains science fiction,” Delclòs added.
“And this is just the beginning,” he said. “In a very small sample, we already identified six different insect orders. The site promises to be a treasure trove.”
A scientific treasure trove
To make every observation count, the team relied on a highly multidisciplinary approach involving methods from geochemistry and paleobotany. Studying the amber from these angles helped them pinpoint the exact age of the fossils, as well as the plants that may have produced the resin. They even borrowed a synchrotron—that is, a particle accelerator—to light the samples and “reveal the fine anatomical details of insects,” Delclòs explained.
“Together, these lines of evidence allow us to reconstruct, with unprecedented accuracy, the ecosystem of a Cretaceous rainforest that once thrived where today lies the Amazon,” he said.
The researchers believe there are more undiscovered amber deposits in South America. The next step is to explore further—which Delclòs is already doing. (No, seriously—he responded to Gizmodo’s interview request while out in the field.)
By identifying and studying the amber, we’ll soon have a better idea of “how this ecosystem started and evolved at the very heart of the equator—something we have never been able to do before in South America,” Delclòs said.
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