![]() "I realized there's only one good explanation for it: harmful algal blooms," Pyenson says. Viruses and other pathogens tend to be species-specific, making it unlikely they'd kill such a diversity of animals. There was no geologic evidence of a powerful tsunami, such as sand deposits where they shouldn't be, and the fossils were in excellent condition, relatively intact. He and colleagues investigated possible explanations-a tsunami, or a virus-but they didn't fit the data. "This is a graveyard, it's not a murder site-the murder happened elsewhere." "The baleen whales were mostly belly-up, and whales are generally only belly-up if they arrive at someplace dead," Pyenson says. Intriguingly, the fossils' positions suggested they hadn't been killed at the site itself. Analysis of the surrounding sediments showed they had been part of a tidal flat environment, and the fossils-a broad mix of both adult and juveniles of different species-were deposited in four distinct layers over the course of about 16,000 years. Over the next few years, Pyenson, Carolina Gustein of the Universidad de Chile and other members of Pyenson's Natural History Museum lab used the digital models and the original fossils to investigate the mystery of the site, called Cerro Ballena (Spanish for "whale hill"). Digital models of the whales could also be shared electronically with other scientists, and the researchers eventually made them publicly available (below: a baleen whale fossil), along with a datasets of their dimensions that allow anyone to print them at any scale. With these digital renderings, Pyenson and other researchers could inspect the fossils in their original context at their leisure, even after they'd been removed. Within a week's time, they used laser-powered digitization methods to create digital 3D renderings of the site, and its fossils, in extreme detail. Soon after the discovery, Pyenson returned to the site with Vince Rossi and Adam Metallo of the Smithsonian Digitization Program Office. Taking a fossil from its site erases its geological context, the main clue Pyenson and other researchers could use in figuring out what caused all these deaths in the first place.Īdam Metallo and Vince Rossi use a high-resolution laser scanner to digitally preserve a whale fossil in its original geologic context. This, of course, is a major no-no in paleontological research. The problem: The road would be widened within two months, and the fossils had to be removed immediately. "At least ten different kinds of marine animals, recurring in four different layers," Pyenson says. ![]() Stumbling upon evidence of the deaths, he and his colleagues were astounded by what they saw-dozens of complete, ancient whale fossils, along with those of several other species, including an extremely rare ancient dolphin species that had only been found a handful of times previously. Then, in October 2011, during the final moments of a paleontological expedition in the fossil-rich region, Smithsonian researcher Nick Pyenson decided to look at the sediments being exposed by the widening of the Pan-American Highway from two lanes to four right near the coast. Geologic subduction pushed the sediment upward by about 130 feet, lifting the mud flats and transforming them into dry land in what's now known as Chile's Atacama Desert. The skeletons, hidden underground, gradually fossilized. These die-offs, known as mass strandings, appeared to have happened over and over, with the animals buried in sediment between each episode.Įpochs passed. Species of sperm whale and a walrus-like whale, both now extinct, also died, along with seals, billfishes, bony fish and aquatic sloths. ![]() Lots of them.Īt least thirty baleen whales died, their bodies washed onto a tidal mudflat and buried over time. ![]() ![]() Sometime between six and nine million years ago, in a stretch of the Pacific Ocean just off of South America, something kept killing whales. ![]()
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