According to a new study published in the journal Palaeontology, two footprints found at Dinosaur Cove in southern Victoria are the oldest avian tracks ever discovered in Australia.
Cretaceous bird tracks on a slab of sandstone found at Dinosaur Cove, southern Victoria, Australia. Image credit: Alan Tait.
“These tracks are evidence that we had sizeable, flying birds living alongside other kinds of dinosaurs on these polar, river floodplains, about 105 million years ago,” said lead author Dr Anthony Martin of Emory University in Atlanta.
The footprints were found on a slab of rock from the early Cretaceous strata of the Eumeralla Formation at Dinosaur Cove, a fossil-bearing site in south-east of Australia.
More than 100 million years ago, the location was a flood plain within a great rift valley that formed as the ancient supercontinent Gondwana broke up and Australia separated from Antarctica.
“The thin-toed tracks in fluvial sandstone were likely made by two individual birds that were about the size of a great egret or a small heron.”
“Rear-pointing toes helped distinguish the tracks as avian, as opposed to a third nearby fossil track that was discovered at the same time, made by a non-avian theropod,” Dr Martin said.
One of the footprints is a very rare flight landing track. “I immediately knew what it was, because I’ve seen many similar tracks made by egrets and herons on the sandy beaches of Georgia.”
He added: “the ancient landing track from Australia has a beautiful skid mark from the back toe dragging in the sand, likely caused as the bird was flapping its wings and coming in for a soft landing.”
“Fossils of landing tracks are rare, and could add to our understanding of the evolution of flight.”
______
Bibliographic information: Martin AJ et al. Oldest known avian footprints from Australia: Eumeralla Formation (Albian), Dinosaur Cove, Victoria. Palaeontology, published online October 25, 2013; doi: 10.1111/pala.12082
