By Jim Leffman via SWNS
The sea where Bristol is once harbored giant ichthyosaurs the size of a blue whale, scientists believe.
Huge bones found in 1850 at Aust Cliff near Bristol, along with similar ones across Europe, have puzzled scientists for years.
No one could work out what animal group the 200 million-year-old giant bones belonged to.
But now researchers at the University of Bonn in Germany say they have solved the mystery as the microstructure of the bones reveals they belong to a giant ichthyosaur.
The study, published in the journal Peer J, says these animals, whose bone fragments have been found in Western and Central Europe could reach 25 to 30 meters in length, a similar size to the modern blue whale.
In 1850 Samuel Stutchbury reported a mysterious find in a scientific journal, a large, cylindrical bone fragment at Aust Cliff.
Over the years similar finds were made in Bonenburg in North Rhine-Westphalia and in the Provence region of France.
All these areas were submerged beneath a huge ocean that covered vast swathes of Western and Central Europe.
Fossil remains from the animal world of that time, including marine and coastal dwellers, have been preserved in the sediment.
Stutchbury assumed hat they came from a labyrinthodontia, an extinct crocodile-like land creature but others claimed it came from a long-necked dinosaur.
However, the microstructure of the fossils indicates that they come from the lower jaw of a gigantic ichthyosaur.
Marcello Perillo studied the mystery as part of his Master’s Thesis in the Institute of Geosciences at the University of Bonn.
He said: “Already by the beginning of the 20th century, some other researchers had theorized that the fossils could possibly be from a gigantic ichthyosaur.
“Bones of similar species generally have a similar structure. Osteohistology, the analysis of bone tissue, can thus be used to draw conclusions about the animal group from which the find originates.
“I compared specimens from South West England, France and Bonenburg,.
“They all displayed a very specific combination of properties. This discovery indicated that they might come from the same animal group.”
He then found the bone wall contained long strands of mineralized collagen, a protein fiber which were interwoven in a characteristic way.
Similar strands have been found in ichthyosaurs in Canada.
Perillo said: “This structure is not found in fossil samples from other animal groups that I have studied,.
“Therefore, it seems highly probable that the fragments in question also belong to an ichthyosaur and that the findings refute the claim that the bones come from a land-living dinosaur.”
It is likely that the fossils come from the lower jaw of a sea creature. By comparing the size of the fragments with the jaws of other species in this animal group, it is possible to deduce the length of the animals.
They could possibly have reached a length of 25 to 30 metres but Perillo said:. “This number is only an estimate and far from certain until, that is, we find more complete fossil remains.
“Nevertheless, they were certainly exceptionally large.
“These huge jaws would have been exposed to strong shearing forces even when the animal was eating normally.
“It is possible that these animals also used their snouts to ram into their prey, similar to the orcas of today. However, this is still pure speculation at this time.”
