Ancient 'Drop Crocs': Discovery of 55-Million-Year-Old Crocodile Eggshells in Australia

Wed Nov 12 2025 15:47:20 GMT+0200 (Eastern European Standard Time)

Scientists have unearthed the oldest crocodile eggshells in Australia, providing evidence of prehistoric tree-climbing crocodiles known as 'drop crocs.'

A groundbreaking discovery in Queensland reveals Australia's oldest known crocodile eggshells, dated at 55 million years old. These belong to mekosuchine crocodiles, which are believed to have been tree-climbers, hunting prey from above—a striking adaptation in the ancient ecological landscape. The findings shed light on the evolution of these unique crocodiles, occurring long before modern species populated the region.

Scientists have unearthed Australia's oldest known crocodile eggshells which may have belonged to drop crocs - creatures that climbed trees to hunt prey below.

The discovery of the 55-million-year-old eggshells was made in a sheep farmer's backyard in Queensland with the findings published in the Journal of Vertebrate Paleontology.

The eggshells belonged to a long-extinct group of crocodiles known as mekosuchines, who lived in inland waters when Australia was part of Antarctica and South America.

Co-author Prof Michael Archer said drop crocs were a bizarre idea but some were perhaps hunting like leopards - dropping out of trees on any unsuspecting thing they fancied for dinner.

Prof Archer, a palaeontologist at the University of New South Wales, noted that mekosuchine crocodiles - which could grow to about five metres - were plentiful 55 million years ago, long before their modern saltwater and freshwater cousins arrived in Australia about 3.8 million years ago.

The drop croc eggshells were discovered several decades ago but only recently analysed with the help of scientists in Spain.

It's a bizarre idea, Prof Archer reflected, but some were probably terrestrial hunters in the forests.

The findings add to earlier discoveries of younger mekosuchine fossils - found in 25-million-year-old deposits in another part of Queensland.

Ever since the early 1980s, he has been part of excavations at a clay pit in Murgon, a small regional town about 270km (168 miles) north-west of Brisbane, known as one of Australia's oldest fossil sites nestled in lush forest.

This same forest was home to the world's oldest-known songbirds, Australia's earliest frogs and snakes, diverse small mammals with South American links, and one of the world's oldest bats, as noted by Dr Michael Stein, another co-author of the report.

Prof Archer reminisced about how in 1983, he and a colleague approached a sheep farmer for permission to excavate in their backyard, leading to the discovery of many fascinating fossils.

With more digging, there will be a lot more surprises to come, he affirmed.