Australia's oldest known crocodile eggshells, dating back 55 million years, have been discovered in Queensland. These eggshells are believed to belong to an extinct group of crocodiles known as mekosuchines, which some scientists hypothesize may have included species that climbed trees.
Discovery Details
The eggshells were found in a sheep farmer's backyard in Murgon, Queensland. The discovery was made several decades ago but has only recently been analyzed by scientists from the University of New South Wales and Spain. The findings have been published in the Journal of Vertebrate Paleontology.
Mekosuchine Crocodiles
Mekosuchine crocodiles, which could grow up to five meters in length, were prevalent 55 million years ago. This period predates the arrival of modern saltwater and freshwater crocodile species in Australia, which occurred approximately 3.8 million years ago. Co-author Professor Michael Archer, a palaeontologist at the University of New South Wales, suggests that some mekosuchine species may have been terrestrial hunters in forest environments, while others were potentially semi-arboreal, exhibiting behaviors described as 'drop crocs.'
Murgon Fossil Site
The Murgon site has been excavated since the early 1980s and is recognized as one of Australia's oldest fossil locations. It was historically a lush forest ecosystem. Dr. Michael Stein, a co-author of the report, noted that this ancient forest also hosted the world's oldest known songbirds, Australia's earliest frogs and snakes, diverse small mammals with South American origins, and one of the world's oldest known bats. Previous discoveries of younger mekosuchine fossils, found in 25-million-year-old deposits, complement these new findings.