Around 500,000 years ago, horses, sloths, and armadillos fell into a sinkhole in what is now Florida and remained there until they were discovered by two men in 2022. Robert Sinibaldi and Joseph Branin found 552 exceptionally preserved animal fossils while diving in the Steinhatchee River, shedding light on a previously unknown period of the Pleistocene ice ages.
The discovery revealed that the animals met their demise in the sinkhole, where they were preserved under layers of sediment for hundreds of thousands of years. The river’s course has changed over time, eventually washing the fossils into the riverbed. Sinibaldi and Branin submitted their findings to the Florida Museum of Natural History, where paleontologists confirmed their origins.
The study provides insight into a little-known period of North American land mammal evolution, specifically the middle Irvingtonian age. It is only the second known site in Florida from this time period, filling a gap in the fossil record. The discovery includes fossils of Holmesina floridanus and septentrionalis, two extinct armadillo-like creatures that show features of both species.
The findings suggest that modern-day Florida was once an open landscape with fewer trees than today. Many of the fossils are from caballines, early horses that evolved to live in open habitats. The researchers found well-preserved teeth that could provide clues on what plants these early horses were eating. An unusual tapir skull may represent a new species or just be an individual from the population.
The discovery highlights the potential for successful collaborations between hobby fossil hunters and professional researchers, as it joins a growing list of vertebrate fossil sites in Florida discovered by amateurs and experts alike.
Source: https://gizmodo.com/a-florida-sink-hole-swallowed-these-animals-500000-years-ago-now-their-bones-reveal-a-lost-world-2000565574