Ancient Crocodile Eggshells Reveal Evidence of Tree-Climbing Hunters in Australia
Murgon, Queensland – Fossilized eggshells unearthed from a Queensland sheep farm are providing new insights into a long-extinct group of crocodiles known as mekosuchines, suggesting some species were capable of climbing trees and ambushing prey – earning them the nickname “drop crocs.” The 55-million-year-old revelation, recently analyzed with the help of Spanish scientists and published in the Journal of Vertebrate Paleontology, pushes back the known timeline of crocodile evolution in Australia and reveals a surprisingly diverse prehistoric ecosystem.
The eggshells were originally discovered decades ago in a clay pit near Murgon, approximately 270km (168 miles) northwest of Brisbane. This site, excavated since the early 1980s, has become renowned for its wealth of fossils dating back to a time when Australia was connected to Antarctica and South America.
“Some were perhaps hunting like leopards – dropping out of trees on any unsuspecting thing they fancied for dinner,” explained Professor Michael Archer, a palaeontologist at the University of New South Wales and co-author of the study. He described the “drop croc” concept as “a bizarre idea,” but added that some mekosuchines were likely “terrestrial hunters in the forests.”
Mekosuchines, which could grow to around five metres in length, thrived in inland waters long before the arrival of modern saltwater and freshwater crocodiles approximately 3.8 million years ago. The eggshell findings corroborate earlier discoveries of 25-million-year-old mekosuchine fossils from another Queensland location,some of which also indicated semi-arboreal,or tree-dwelling,behavior.
The Murgon site has also yielded fossils of the world’s oldest known songbirds, Australia’s earliest frogs and snakes, a variety of small mammals with South american connections, and one of the world’s oldest known bats, according to Dr. Michael Stein, a co-author of the report.
Professor Archer recounted obtaining permission to excavate the farm in 1983, stating, “We drove to Murgon, parked the car on the side of the road, grabbed our shovels, knocked on the door and asked if we could dig up their backyard…they grinned and said ‘of course!'” He added, “And, quite clearly, from the many engaging animals that we’ve already found in this deposit as 1983, we certainly know that with more digging there will be a lot more surprises to come.”
