“When the results came back that this was a short-faced bear dated to roughly 17,000 years ago, we were all really intrigued about the implications for island biogeography and ecology,” said Rick. Torben Rick, who participated in the Daisy Cave excavations and is now at the Smithsonian’s National Museum of Natural History, was excited to apply a suite of new, minimally destructive technologies (aDNA, proteomics, etc.) to help resolve the questions surrounding this mysterious bone. These two independent molecular analyses, combined with traditional morphological evidence of the shape and size of the toe, confirmed its identity as belonging, unexpectedly, to a giant short-faced bear. In parallel, the specimen was analyzed for ancient bone proteins (collagen) at the University of Manchester in the UK, producing chemical fingerprints that most closely matched a reference of the spectacled bear from South America- – the only living relative of the short-faced bear. Luckily, its DNA was well-preserved, too,” said Nihan Dagtas, who successfully extracted amplifiable DNA at the world-class clean room facility of LMAMR. I remember having a hard time cutting the bone piece out it was such a rigid, morphologically well-preserved sample, thanks to the cave’s environment. “From the moment I heard this could be a unique specimen, I handled it with extra care. In 2016, the toe bone arrived at the Laboratories of Molecular Anthropology & Microbiome Research at the University of Oklahoma. Was it from a large grizzly or black bear? The specimen rested safely in Erlandson’s lab for more than 20 years. “Found in a stratum dated to over 13,000 years ago, the bone posed a significant mystery,” said Jon Erlandson, a University of Oregon professor who has directed investigations at Daisy Cave since the 1990s. This little bone, excavated in 1996, was long assumed to be from a seal, but experts suggested that it was from a bear – the first and only bear ever recorded for California’s Channel Islands. While this is not the first strange mammal to be found on the California Channel Islands, which was once home to a pygmy mammoth and a giant mouse, it is the first case of a potentially native megafaunal carnivore, which would challenge previous models of colonization and evolution of the islands’s biodiversity. – once roamed diverse environments from Alaska to Mexico, but has never been found in such an isolated island context. This fearsome beast – weighing by some estimates 2,000 lbs. Today, a team of researchers from the University of Oklahoma, the Smithsonian National Museum of Natural History, the University of Oregon and others report the first occurrence of the extinct giant short-faced bear, Arctodus simus, from the California Channel Islands. This importance is only growing with new excavation, chemical, and biomolecular techniques, expanding our vision of this dynamic ecosystem and its enduring importance to humans and wildlife alike. The California Channel Islands are renowned for their archaeological, biological and paleontological significance and richness, containing some of the most important early human sites in North America.
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