A fossil of the oldest known predator has been identified by UK scientists.
The 560-million-year-old specimen, found in Leicestershire’s Charnwood Forest, is likely a precursor to cnidarians — the group of animals that today includes jellyfish.
The researchers named Auroralumina attenboroughii to the fossil. It is a tribute to naturalist David Attenborough, the BBC’s historic presenter.
The first part of the name is a reference to a Latin expression meaning “dawn lantern”.
“I think it looks like an Olympic torch, with its tentacles being the flames,” says Frankie Dunn of the University of Oxford, who wrote an article about the discovery in the journal Nature Ecology and Evolution.
Not only does the fossil place evidence of predation in the animal kingdom about 20 million years earlier than previously thought, it is also likely the first example of such an organism with a true skeleton.
The outline of the 20 centimeters tall creature sat on a long, sloping slab of a quarry, surrounded by other fossils.
They are all believed to have been buried by a stream of sediment and ash that flowed down the undersea flank of an ancient volcano.
The area where the fossil lay was originally discovered in 2007, when researchers cleaned the rock face of Charnwood with high-pressure hoses.
It took them 15 years to understand the location — only then did they find the exact position where the Auroralumina.
The Leicestershire region is famous for what it tells us about the period known as the Ediacaran (635 to 538 million years ago).
This is the period of geological history that immediately precedes the Cambrian, which witnessed a great explosion in the number and diversity of life forms on Earth.
It was in the Cambrian (between 538 and 485 million years ago) that the “model” for many groups of modern animals was set.
But Auroralumina proves that its grouping, the cnidarians, has a heritage that extends farther back, all the way to the Ediacaran.
“It’s a strong indication that there were more modern-looking organisms in the Precambrian. This means that the ‘wick’ for the Cambrian explosion was probably quite long,” explains Phil Wilby, head of paleontology at the British Geological Survey.
While the name “cnidaria” may not be all that familiar, the animals that fall into this category are quite familiar: corals, jellyfish, and anemones. One of their features is the stinging cells that they used to capture their prey.
Dunn’s analysis of the characteristics of Auroralumina links the animal to the medusozoa subgroup within cnidarians.
Medusozoans go through several stages throughout their complex life cycles. In one of them, they look like a mass anchored to the bottom of the sea. Later, they transform into floating creatures in the breeding season.
During this floating stage, they take on an umbrella form with stinging tentacles. They become a kind of jellyfish.
Auroralumina therefore more closely resembles a medusozoan in its immobile, rooted stage.
incomplete discovery
“What’s really interesting is that the animal forked. So you have these two ‘goblets’ stuck near its base, and there was a continuous piece of skeleton going down to the sea floor, but that piece we didn’t find. Unfortunately, the fossil is incomplete,” Dunn said.
The bifurcation — the splitting into two branches or parts — is another novelty in the newly discovered fossil.
Paleontologists from around the world visit Charnwood Forest.
Its main attraction is the fossil known as charnia masoni.
This one was found in the 1950s by two students — Roger Mason and Tina Negus — and was the first Precambrian fossil to come to light.
THE Charnia it was also later found in the rocks that make up the Ediacaran Hills in Australia, which give its name to the Ediacaran period.
She has a strange looking life form resembling a fern leaf, but scientists are convinced that she was indeed some kind of animal.
There is also an example of Auroralumina of just 40 centimeters in the same location.
The name David Attenborough was used to name the animal because he grew up in this central part of England.
“When I was at school in Leicester, I was an avid fossil hunter,” he recalled.
“The rocks on which the Auroralumina was discovered were thought to be so ancient that they dated back to long before the beginning of life on the planet. So I never looked for fossils there,” he said.
“A few years later, a boy at my old school found a fossil and proved the experts wrong. He was rewarded: his name was used to name the find. Now I’ve almost caught up with him and I’m really delighted,” says Attenborough.
– This text was published at https://www.bbc.com/portuguese/geral-62300687
