Geology
Dale Gnidovec
Sun, January 8, 2023
Ichthyosaurs swam the world's oceans at the same time that dinosaurs ruled the land. A fossil of the dolphin-like seagoing reptile discovered on Scotland's Isle of Skye is one of the thousands of marine fossils found from the Jurassic Period.
Sometimes fossils are not what they seem.
That is especially true of ones that have been in museums for a long time. A recently reported bit of research by a team of three scientists, from England, Germany, and the U.S., discussed a good example.
The specimen was that of an ichthyosaur in the collections of the Reutlingen Natural History Museum in southern Germany, which bought it in 1984. Ichthyosaurs were marine reptiles that co-existed with the dinosaurs. Most were about the size and shape of modern dolphins, but some got much bigger — one species may have been 85 feet long.
They were the first large prehistoric animals to be studied scientifically, as early as 1814, decades before dinosaurs were even discovered. Thousands of specimens were collected, especially from the Early Jurassic rocks along the southern coast of England. Many found their way onto the walls of private mansions as decorations.
Geology:Giant lumbering ground sloth inhabited much of North America in Ice Age | Geology
The specimen in question was supposedly collected in England, but paleontologists looking at photographs felt that something didn’t look quite right.
Close examination of the actual fossil showed why. The skull, while containing a few real fossil teeth, is fake, carved from plaster. The vertebrae (individual elements of the backbone) are real, but from a number of different individuals, and some are in the wrong position.
Dale Gnidovec
Also, the rock enclosing the pelvis and hind fins is a slightly different shade of grey. Further study showed that the pelvis/hind fin section was indeed from England, but the rest of the skeleton came from Germany, from the shale quarries around Holzmaden, Germany, which has also produced thousands of Jurassic ichthyosaur specimens.
It would be one thing if the parts were from the same species, but not only were they from different species, they were from animals that lived at different times.
Geology: The sands of time show impact of great quake of Lisbon in 1775 | Geology
Imbedded in the rock containing the bones of the ichthyosaurs were fossils of ammonites, mollusks related to the modern chambered nautilus. Ammonites were very abundant in Mesozoic seas, and they evolved rapidly, with new species constantly replacing old ones. Each species lived for only a short period of time, so like coins that have their date of manufacture stamped on them, they can be used to date other fossils they occur with.
The ammonites showed that most of the skeleton came from an animal that was alive around 179 million years ago. The pelvis and hind fin came from an animal that was living around 196 million years ago, 17 million years earlier.
The scientist dubbed the specimen the ‘iffyosaur’.
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Dale Gnidovec is curator of the Orton Geological Museum at Ohio State University. Contact him at gnidovec.1@osu.edu
This article originally appeared on The Columbus Dispatch: Scientists thought they had an ichthyosaur fossil but it was fake
Dale Gnidovec
Sun, January 8, 2023
Ichthyosaurs swam the world's oceans at the same time that dinosaurs ruled the land. A fossil of the dolphin-like seagoing reptile discovered on Scotland's Isle of Skye is one of the thousands of marine fossils found from the Jurassic Period.
Sometimes fossils are not what they seem.
That is especially true of ones that have been in museums for a long time. A recently reported bit of research by a team of three scientists, from England, Germany, and the U.S., discussed a good example.
The specimen was that of an ichthyosaur in the collections of the Reutlingen Natural History Museum in southern Germany, which bought it in 1984. Ichthyosaurs were marine reptiles that co-existed with the dinosaurs. Most were about the size and shape of modern dolphins, but some got much bigger — one species may have been 85 feet long.
They were the first large prehistoric animals to be studied scientifically, as early as 1814, decades before dinosaurs were even discovered. Thousands of specimens were collected, especially from the Early Jurassic rocks along the southern coast of England. Many found their way onto the walls of private mansions as decorations.
Geology:Giant lumbering ground sloth inhabited much of North America in Ice Age | Geology
The specimen in question was supposedly collected in England, but paleontologists looking at photographs felt that something didn’t look quite right.
Close examination of the actual fossil showed why. The skull, while containing a few real fossil teeth, is fake, carved from plaster. The vertebrae (individual elements of the backbone) are real, but from a number of different individuals, and some are in the wrong position.
Dale Gnidovec
Also, the rock enclosing the pelvis and hind fins is a slightly different shade of grey. Further study showed that the pelvis/hind fin section was indeed from England, but the rest of the skeleton came from Germany, from the shale quarries around Holzmaden, Germany, which has also produced thousands of Jurassic ichthyosaur specimens.
It would be one thing if the parts were from the same species, but not only were they from different species, they were from animals that lived at different times.
Geology: The sands of time show impact of great quake of Lisbon in 1775 | Geology
Imbedded in the rock containing the bones of the ichthyosaurs were fossils of ammonites, mollusks related to the modern chambered nautilus. Ammonites were very abundant in Mesozoic seas, and they evolved rapidly, with new species constantly replacing old ones. Each species lived for only a short period of time, so like coins that have their date of manufacture stamped on them, they can be used to date other fossils they occur with.
The ammonites showed that most of the skeleton came from an animal that was alive around 179 million years ago. The pelvis and hind fin came from an animal that was living around 196 million years ago, 17 million years earlier.
The scientist dubbed the specimen the ‘iffyosaur’.
Geology:Geology: Ash shows ancient air
Dale Gnidovec is curator of the Orton Geological Museum at Ohio State University. Contact him at gnidovec.1@osu.edu
This article originally appeared on The Columbus Dispatch: Scientists thought they had an ichthyosaur fossil but it was fake
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