The footprints of a reptile-like creature appear to have been laid down around 356 million years ago, pushing back the earliest known instance of animals emerging from the water to live on land
By James Woodford
14 May 2025
An artist’s impression of the lizard-like creature making tracks
Marcin Ambrozik
Evidence of the earliest known reptile-like animal, an ancestor of many four-limbed creatures including birds, reptiles and mammals, has been found in Victoria, Australia. The discovery could push back the timing of when these animals began to emerge from the water to live solely on land, one of the most important evolutionary events of life on Earth, though not everyone is convinced.
In 2021, a pair of amateur fossil enthusiasts exploring the banks of the Broken river, near Mansfield, Victoria, found a slab of sandstone, around 40 centimetres across, with three sets of tracks that appear to have been made by the same species of tetrapod – or four-legged animal. Two of the sets show signs of five digits, with curved claws.
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The fossil was brought to the attention of John Long at Flinders University in Adelaide, Australia, and his colleagues, who dated the slab to around 356 million years ago. This is more than 35 million years earlier than the previous oldest clawed fossils, which were found in Nova Scotia, Canada.
“We can see beautiful, five-fingered hands and hooked claws in these new trackways,” says Long. These are a “dead giveaway” that this was an amniote, or creature whose young develop inside amniotic fluid, he says. This category includes those that grow inside an egg, as with reptiles, or inside the body, as in mammals, including humans.
It also rules out the possibility that the animal was an amphibian, says Long. The first four-legged land animals are thought to have been amphibians, but their young would have had to pass through a larval stage, forcing them to return to water rather than living out their whole life cycle on land. “None of the early amphibians have well developed claws at the end of their fingers and feet,” he says.