Rick E. Otto, University of Nebraska State Museum
Death was everywhere. Animal carcasses littered the ground, and bodies were buried in local watering holes as ash blew away everything in its path. For some, death came quickly, but for others it came slowly and painfully.
This was the scene immediately following the eruption of a supervolcano about 1,600 kilometers (900 miles) away in Idaho. The eruption was so powerful that it obliterated the volcano itself, leaving a crater 80 kilometers (50 miles) wide, and spewed ash clouds that were carried far away by winds and killed nearly every living thing that inhaled them. This was especially true here in Nebraska, where animals large and small succumbed to the eruption’s deadly emissions.
Eventually, all traces of this horrific event were buried and life continued, evolved and changed, so that millions of years later, in the summer of 1971, Michael Voorhees was able to enjoy another joyous day of exploration.
Find a rhino
He would spend each summer making geological maps of his Nebraska hometown, going from farm to farm, walking the properties examining rocks and asking if he could look for fossils. “I was basically a kid at heart, and being a paleontologist for a summer was like heaven for me,” Voorhees, a retired University of Georgia professor, told Ars.
At one farm, his eye was caught by a layer of volcanic ash, a valuable material used by geologists and paleontologists to date sediments. But as he got closer, Noticed “It’s really interesting that we found a mandible that was obviously still attached to the skull!” he said. “What we’ve found is mainly isolated bones and teeth.”
The skull belonged to a young rhino. Voorhees and several of his students returned to the site to excavate further, unearthing the rhino’s remaining fully articulated remains (i.e., the bones of the skeleton were connected just as they would have been in life). Further excavation revealed the complete skeletons of five or six more rhinos. This was enough to fund a larger excavation by National Geographic in 1978-1979. The workers collected an astonishing total of 70 complete skeletons of rhinos, along with many other animals.
To put this in perspective, most fossil sites, even the most impressive ones with multiple animals preserved, consist primarily of dismembered skeletons — pieces of a puzzle that paleontologists have painstakingly put together — but here they found something no other site has ever found before: a large number of complete skeletons preserved right where they died.
Realizing there was more to discover, Voorhies and others called on the larger Nebraska community to help protect the area. Thanks to hard work and generous local donations, Ashfall Fossil Beds Park It opened to the public in 1991 and has two full-time employees.
The fossils that were discovered are now left in place, exposed in the exact spot where they were found. Hubbard Rhino BurnInside the barn, excavation takes place at a much slower, steady pace. pace The site is more active than it was in the 1970s, mainly due to the small number of seasonal workers (mostly university students) who take turns excavating further each summer.
Photo by Rick E. Otto, University of Nebraska State Museum
Complete Ecosystem
Nearly 50 years of excavation and research have revealed the untold story of a Nebraska disaster and its aftermath. Rhino, cameland sabre-toothed tigers were a common animal to see.
But to understand that story, we need some background. The area known today as the ash-fall bed was actually a Miocene waterhole that was frequented by a diverse range of animals. We know this because the fossils of those animals can be found in the sandy layer at the bottom of the waterhole, a layer that was not affected by the supervolcanic eruption.
Rick Otto was one of the students who unearthed the fossils in 1978. He became Ashfall’s manager in 1991 and will retire in late 2023. “An animal had died of natural causes around the waterhole at Ashfall before the ash storm,” Otto told ARS, describing the fossils found in the sand. The carcass may have been eaten and then trampled by some of the larger animals visiting the waterhole, “which caused the bones to become buried in the sand.”
