The sponge fossil was found in the mud in a rock shelter by a group of archaeologists led by Prof. Martin Bartsch from the Max Planck Institute for Geosciences in Berlin.
The fossil, dubbed sponge fossil 2, measures over 20cm in length and weighs almost 6kg (13.5lbs).
“We were delighted to find this fossil in a shelter, and we knew that this was something special.
We had the fossil in our hands and it made us really excited,” said Dr. Stefan Schubert, who was a postdoctoral researcher in Bartssch’s lab at the time.
“But we were also worried that the fossil might be too big to be a sponge.
We thought that maybe it was a large, round, living thing.”
Schubert and Bartsche’s team of archaeologists excavated the fossil, called sponge fossil 1, in the early 1990s, when they were working on a project to reconstruct how ancient people had used the mud-filled rock shelter known as the Bremen Stone Shelter, which is now located in the Netherlands.
Bartsch’s team uncovered the fossil at a site in the southern Netherlands in 1999, when the group was excavating an area that had previously been used as a storage site.
Schulter was not the first person to find the fossil.
A team led by a British geologist, Prof. David Atherton, found another fossil, the giant sponge-like animal, in 2004.
When the Bartsches and Athertons found the fossil of sponge fossil 4, they decided to investigate further.
In 2011, Bartssche and Aterton published their results in the journal Scientific Reports.
Now, they have published their first paper in Science, and the news has been greeted with excitement by sponge fossil enthusiasts around the world.
Bartssch, Bartsch and Aterson were able to show that the sponge fossil is in fact a sponge-type animal that has had the ability to eat rock.
They also showed that the fossils fossilized within the rock shelter could be used as fossils for reconstructing a number of other species, including fish.
Scientists hope that the finding will help to unravel how fossils evolved in the sea environment that covered the continent.
If confirmed, the discovery could have implications for a number a ancient marine ecosystems.
More information: Schule Fossil: sponge fossil or sponge-fossil?
Nature Communications, DOI: 10.1038/s41562-017-0089-5