Earliest animal on Earth with skeleton discovered

Scientists have unearthed fossils of what they believe is the oldest animal with a skeleton that shaped like a thimble and lived on the seafloor more than half a billion years ago.

Hundreds of fossils of the animal, named Coronacollina acula, were discovered in ancient sandstone beds in south Australia, suggesting the area was once a shallow seafloor.

Researchers behind the discovery said these findings shed light on the evolution of early life on Earth and could also help scientists recognise life elsewhere in the universe.

"Coronacollina is an example of one of the earliest animals on Earth," researcher Erica Clites, a paleontologist at Glen Canyon National Recreation Area in Arizona, was quoted as saying by LiveScience.

The animal, which measured up to 0.6 inches (1.5cm)high and nearly 0.9 inches (2.2cm) wide, sported at least four 14.5 inches-long neelelike "spicules" radiating from the top of its body, which the scientists think it used as keletons to hold its body somewhat like the poles of a tent.

C-acula was likely not capable of locomotion, and so probably fed as sponge does, filtering food from the water, the researchers said.

The creature is between 550 million and 560 million years old belonging to the mysterious Ediacaran period, when life first became large enough to be seen with the naked eye. The animals from the Ediacaran are almost universally bizarre, and very difficult to link with any modern animal groups.

Clites said it was thought that animals were soft-bodied and had no hard parts, yet Coronacollina does have hard parts until the Cambrian period.

"Coronacollina provides the first unequivocal evidence of a macroscopic, multi-element organism possessing skeletal support structures within the Ediacaran," she said, adding that C-acula could be a missing link between the Ediacaran and Cambrian eras.

These findings, published in the journal Geology, could one day also help scientists identify signs of life on alien worlds, Clites said.