They mentioned that on the Fossil Forum too!
No, it's artificial colour from the light I used for the photos.
Natural colour :
Turtle Fossil
- Thread starter Moozillion
- Start date
No, it's artificial colour from the light I used for the photos.
Natural colour :
Cool posts! I loved catching up today! 
It made me think of our somewhat embarrassing claim to fame in northern Michigan: the man-eating clam. The sign says it is a Tridacna gigas located a tourist attraction called Sea Shell City off I-75 not far south of the Mackinac Bridge. Here's an article with photos about it, but do watch out for some terrible puns!
http://www.mlive.com/travel/index.ssf/2017/08/sea_shell_city_cheboygan_michi.html
It made me think of our somewhat embarrassing claim to fame in northern Michigan: the man-eating clam. The sign says it is a Tridacna gigas located a tourist attraction called Sea Shell City off I-75 not far south of the Mackinac Bridge. Here's an article with photos about it, but do watch out for some terrible puns! http://www.mlive.com/travel/index.ssf/2017/08/sea_shell_city_cheboygan_michi.html
Yes, the famous giant clams, wonderful molluscs.Cool posts! I loved catching up today!
http://www.mlive.com/travel/index.ssf/2017/08/sea_shell_city_cheboygan_michi.html
But not really man-eaters or even harmful.
Inoceramus seenstrup, the biggest fossil pelecypod (bivalve) .
CarolM
Well-Known Member
Wow, that is HUGE!Yes, the famous giant clams, wonderful molluscs.
But not really man-eaters or even harmful.
Inoceramus seenstrup, the biggest fossil pelecypod (bivalve) .
View attachment 231202
Raqib Farid
Well-Known Member
How to reserve these fossils?
I mean my cousin had a red ears slidder turtle. It died some days ago, he buried it in sand. So how much time it will take to completely decompress? So he will retrieve its shell?
It won't be fossilized.
You are just talking about decomposition of the soft parts to leave just the shell and bones, I think.
In normal conditions this would take a minimum of five months but in dry desert sand I would think mummification is possible and it may take much longer.
I would wait at least 8 months.
https://answers.yahoo.com/question/index?qid=20100611200419AALeJa4
CarolM
Well-Known Member
That is sad news. It has little value other than to the national park. Just so wrong when people take things that don't belong to them.[emoji22]
This kind of news always breaks my heart.
Here’s the megshark tooth that I have. But it’s mine free and clear and stollen from no one other than the ground it was in 
originally I had two large ones, but at Christmas I gave my daughter her pick, and she picked the one I would have. I’ve got a handful of the usual small ones out in the garage but I’m not gonna go get them.
originally I had two large ones, but at Christmas I gave my daughter her pick, and she picked the one I would have. I’ve got a handful of the usual small ones out in the garage but I’m not gonna go get them.
Maybe I’ve posted this in the past, or maybe someone beat me to it, regardless here y’all go…
http://blogs.discovermagazine.com/c...edium=feed&utm_source=feedburner#.WqsERCJlCEc
http://blogs.discovermagazine.com/c...edium=feed&utm_source=feedburner#.WqsERCJlCEc
As I'm currently working in the digital asset management field, I could really relate to this article. I shared it with my coworkers. Cheers!
Fossil Brain Case Reveals New Insights About Ancient Sharks
A new study led by Museum scientists provides new insights into a 320 million-year-old shark that was previously only known by its unusual teeth and fragmented jaws. A newly uncovered fossilized brain case of Carcharopsis wortheni, found in the Fayetteville Shale of Arkansas, is helping researchers better place the ancient shark in the tree of life.
Carcharopsis lived during a critical point in evolutionary history, following the end-Devonian extinction event, when nearly 95 percent of vertebrate species went extinct. The late Paleozoic shark was originally described in 1843 based on its distinctive serrated teeth, a feature that is common in modern sharks but rarely found in early shark specimens.
Great white shark swims through a school of fish.
Great white sharks, Carcharodon carcharias, are named for their serrated (carcharos) teeth (odon).
Courtesy of Terry Goss/Wikimedia Commons
“They look a little like what you’d see in a great white shark, but 320 million years old and with different enamel,” said lead author Allison Bronson, a Ph.D. student in the Museum’s Richard Gilder Graduate School. “This is really early to see serrated teeth.”
CT scan of fragmented Carcharopsis skull.
The first known cranium fossil belonging to Carcharopsis was discovered in 2007 by Royal Mapes, a research associate at the American Museum of Natural History.
Allison Bronson
The first known cranium belonging to the extinct shark was discovered in 2007 by Royal Mapes, a retired Ohio University professor and Museum research associate, who donated the specimen along with some 540,000 other fossils to the Museum. Mapes is a coauthor on the new Carcharopsis study, published in the journal Papers in Palaeontology, along with Division of Paleontology Curator John Maisey.
[Watch the video below for more about the Mapes collection at the Museum, including fossil shark specimens.]
The researchers used high-resolution computed tomography (CT) imaging to examine the cranium, a tooth, and an isolated tooth base. Using the scans, they were able to reconstruct the internal canals of the teeth for the first time and found that these are similar to those found in modern sharks.
The arrangement of the shark’s blood vessels—also revealed through CT scans—suggests that Carcharopsis was probably closely related to the group of ancient cartilaginous fish from which today’s sharks and rays evolved. However, more complete fossils are needed to firmly position it in the tree of life.
A new study led by Museum scientists provides new insights into a 320 million-year-old shark that was previously only known by its unusual teeth and fragmented jaws. A newly uncovered fossilized brain case of Carcharopsis wortheni, found in the Fayetteville Shale of Arkansas, is helping researchers better place the ancient shark in the tree of life.
Carcharopsis lived during a critical point in evolutionary history, following the end-Devonian extinction event, when nearly 95 percent of vertebrate species went extinct. The late Paleozoic shark was originally described in 1843 based on its distinctive serrated teeth, a feature that is common in modern sharks but rarely found in early shark specimens.
Great white shark swims through a school of fish.
Great white sharks, Carcharodon carcharias, are named for their serrated (carcharos) teeth (odon).
Courtesy of Terry Goss/Wikimedia Commons
“They look a little like what you’d see in a great white shark, but 320 million years old and with different enamel,” said lead author Allison Bronson, a Ph.D. student in the Museum’s Richard Gilder Graduate School. “This is really early to see serrated teeth.”
CT scan of fragmented Carcharopsis skull.
The first known cranium fossil belonging to Carcharopsis was discovered in 2007 by Royal Mapes, a research associate at the American Museum of Natural History.
Allison Bronson
The first known cranium belonging to the extinct shark was discovered in 2007 by Royal Mapes, a retired Ohio University professor and Museum research associate, who donated the specimen along with some 540,000 other fossils to the Museum. Mapes is a coauthor on the new Carcharopsis study, published in the journal Papers in Palaeontology, along with Division of Paleontology Curator John Maisey.
[Watch the video below for more about the Mapes collection at the Museum, including fossil shark specimens.]
The researchers used high-resolution computed tomography (CT) imaging to examine the cranium, a tooth, and an isolated tooth base. Using the scans, they were able to reconstruct the internal canals of the teeth for the first time and found that these are similar to those found in modern sharks.
The arrangement of the shark’s blood vessels—also revealed through CT scans—suggests that Carcharopsis was probably closely related to the group of ancient cartilaginous fish from which today’s sharks and rays evolved. However, more complete fossils are needed to firmly position it in the tree of life.
FIELD HERPETOLOGY OF THE SOUTHWEST
Southwestern Research Station 27 July–5August, 2018
This 9-day course will introduce participants to an outstanding diversity of am- phibians and reptiles of Arizona’s Chiricahua Mountains and surrounding deserts.
Labs and lectures will focus on identi cation and ecology of herps. The majority of time will be spent in the eld, hiking through low and high elevation habitat.
For more information about the course, contact Geoffrey Bender. Ph: 520-558-2396; email: [email protected] http://www.amnh.org/our-research/southwestern-research-station/education/ field-herpetology-of-the-southwest
Southwestern Research Station 27 July–5August, 2018
This 9-day course will introduce participants to an outstanding diversity of am- phibians and reptiles of Arizona’s Chiricahua Mountains and surrounding deserts.
Labs and lectures will focus on identi cation and ecology of herps. The majority of time will be spent in the eld, hiking through low and high elevation habitat.
For more information about the course, contact Geoffrey Bender. Ph: 520-558-2396; email: [email protected] http://www.amnh.org/our-research/southwestern-research-station/education/ field-herpetology-of-the-southwest
Turtle shells help decode complex links between modern, fossil species
March 28, 2018
Source: Florida Museum of Natural History
Summary: A new study shows how scientists can use animals' physical features -- also known as morphology -- to make connections between a modern species and its fossilized relatives, even if they look strikingly different.
Eastern box turtles display a dizzying amount of variation, both in modern and fossil specimens. But plotting shell shape reveals patterns and captures aspects like curvature -- things that are hard to measure in just a single linear feature.
Credit: Coleman Sheehy / Florida Museum
Imagine that Labradors and golden retrievers died out a million years ago, leaving only fossilized skeletons behind. Without the help of DNA, how could we determine that a fossil Labrador, a fossil retriever and a modern Chihuahua all belong to the same species, Canis lupus familiaris? And could we look at the wide variety of dogs today to gain clues about lost diversity in the past?
A new study by Florida Museum of Natural History researcher Natasha Vitek shows how scientists can use animals' physical features -- also known as morphology -- to make connections between a modern species and its fossilized relatives, even if they look strikingly different.
"We can't magically create more fossils," said Vitek, a doctoral candidate in vertebrate paleontology. "A lot of it is trying to figure out what we can do with what we have at hand to find diversity within a species -- diversity we no longer have.”
Scientists often use color, sexual differences, soft tissues, signs of age and DNA to analyze variation within modern species. But these can be missing in fossil specimens.
Vitek relied on a technique known as geometric morphometrics, a way of quantifying an object's shape, to test whether shape is a reliable way to tease out the subtle relationships between species, subspecies and individuals of the same species that just look different from each other.
She used eastern box turtles, Terrapene carolina -- a species that comes in all kinds of shapes, sizes and colors -- to make links between the rich variation in modern specimens and their fossil relatives from as far back as the Pleistocene, from about 2.6 million to about 11,700 years ago.
Unfortunately, turtles don't make anything easy.
Modern eastern box turtles display a dizzying amount of variation. A box turtle in Oklahoma can be straw-colored while the same species in Florida is dark with yellow sunburst patterns. Adult box turtles also come in a wide array of sizes with no direct link between size and age. A small turtle in one location could be the same size or older than a large turtle of the same species in another location, even within a short distance.
Similar levels of variation also crop up in fossil eastern box turtles. How different must two turtles be to indicate that they belong to different species or subspecies?
To make sure she was "comparing apples to apples," Vitek only analyzed the shape of eastern box turtle shells, which preserve well and are common in the fossil record.
In doing so, she was wading into a debate about eastern box turtle variation that has lasted more than 80 years, with some scientists suggesting that fossil and modern box turtles are all the same species, while others -- pointing to a distinction in size or shape -- hypothesizing that some fossils represented a separate, extinct species. Some researchers have also argued that certain subtle differences between fossils are evidence of various subspecies.
Vitek, who began the study as a master's student at the University of Texas at Austin, compared 435 shells of modern eastern box turtles and 57 shells of fossil specimens, analyzing changes in location, shape, size and sex.
"It's almost 'more money, more problems,'" Vitek said. "You'd think that with so many fossils, it would be great, but it just means that you can't hide from all the natural complexity.”
To find a signal in the noise, she used geometric morphometrics to plot shell shape into a series of coordinates, "like a connect-the-dots puzzle," she said, which created a more complete model of a shape in space.
"This allows you to see how that overall constellation of points is changing from shape to shape," Vitek said. "You might see whole new patterns you would never have thought to measure before and capture things like curvature -- things that are really hard to measure in just a single linear feature.”
Her results showed that scientists on both sides of the debate are partially right.
The argument that modern variation in eastern box turtles mirrors variation in fossil specimens of the same species does have some merit.
"It's not like we hit the fossil record and there's a hard boundary between what's extinct and what still exists today," she said. "Just like we'd expect from evolution, there is a gradient of variation that carries through to modern box turtles. Having some shells that aren't that different is reassuring in the sense that, yes, some species do go back in time."
But, she added, some shells likely do belong to lost subspecies, existing subspecies or closely related extinct species.
"Some sites have shells that are not only bigger than modern eastern box turtles but also very different," she said. "There is lost variation in the eastern box turtle record. It turns out that if you go back to fossils, there is even more diversity than you would be able to pick up just by studying today's box turtles.”
Vitek said she is hopeful her study will spur more researchers to look deeper at bony structures within species as a means of detecting variation in fossils.
"We're doing a great job of seeing what drives patterns like mouse coat color, but let's also see what drives patterns in things like mouse teeth and arm bones," she said. "There's a lot of opportunity to start better documenting what the morphology we pick up in the fossil record might actually mean in terms of evolution."
Story Source:
Materials provided by Florida Museum of Natural History. Original written by Natalie van Hoose. Note: Content may be edited for style and length.
Journal Reference:
Natasha S. Vitek. Delineating modern variation from extinct morphology in the fossil record using shells of the Eastern Box Turtle (Terrapene carolina). PLOS ONE, 2018; 13 (3): e0193437 DOI: 10.1371/journal.pone.0193437
March 28, 2018
Source: Florida Museum of Natural History
Summary: A new study shows how scientists can use animals' physical features -- also known as morphology -- to make connections between a modern species and its fossilized relatives, even if they look strikingly different.
Eastern box turtles display a dizzying amount of variation, both in modern and fossil specimens. But plotting shell shape reveals patterns and captures aspects like curvature -- things that are hard to measure in just a single linear feature.
Credit: Coleman Sheehy / Florida Museum
Imagine that Labradors and golden retrievers died out a million years ago, leaving only fossilized skeletons behind. Without the help of DNA, how could we determine that a fossil Labrador, a fossil retriever and a modern Chihuahua all belong to the same species, Canis lupus familiaris? And could we look at the wide variety of dogs today to gain clues about lost diversity in the past?
A new study by Florida Museum of Natural History researcher Natasha Vitek shows how scientists can use animals' physical features -- also known as morphology -- to make connections between a modern species and its fossilized relatives, even if they look strikingly different.
"We can't magically create more fossils," said Vitek, a doctoral candidate in vertebrate paleontology. "A lot of it is trying to figure out what we can do with what we have at hand to find diversity within a species -- diversity we no longer have.”
Scientists often use color, sexual differences, soft tissues, signs of age and DNA to analyze variation within modern species. But these can be missing in fossil specimens.
Vitek relied on a technique known as geometric morphometrics, a way of quantifying an object's shape, to test whether shape is a reliable way to tease out the subtle relationships between species, subspecies and individuals of the same species that just look different from each other.
She used eastern box turtles, Terrapene carolina -- a species that comes in all kinds of shapes, sizes and colors -- to make links between the rich variation in modern specimens and their fossil relatives from as far back as the Pleistocene, from about 2.6 million to about 11,700 years ago.
Unfortunately, turtles don't make anything easy.
Modern eastern box turtles display a dizzying amount of variation. A box turtle in Oklahoma can be straw-colored while the same species in Florida is dark with yellow sunburst patterns. Adult box turtles also come in a wide array of sizes with no direct link between size and age. A small turtle in one location could be the same size or older than a large turtle of the same species in another location, even within a short distance.
Similar levels of variation also crop up in fossil eastern box turtles. How different must two turtles be to indicate that they belong to different species or subspecies?
To make sure she was "comparing apples to apples," Vitek only analyzed the shape of eastern box turtle shells, which preserve well and are common in the fossil record.
In doing so, she was wading into a debate about eastern box turtle variation that has lasted more than 80 years, with some scientists suggesting that fossil and modern box turtles are all the same species, while others -- pointing to a distinction in size or shape -- hypothesizing that some fossils represented a separate, extinct species. Some researchers have also argued that certain subtle differences between fossils are evidence of various subspecies.
Vitek, who began the study as a master's student at the University of Texas at Austin, compared 435 shells of modern eastern box turtles and 57 shells of fossil specimens, analyzing changes in location, shape, size and sex.
"It's almost 'more money, more problems,'" Vitek said. "You'd think that with so many fossils, it would be great, but it just means that you can't hide from all the natural complexity.”
To find a signal in the noise, she used geometric morphometrics to plot shell shape into a series of coordinates, "like a connect-the-dots puzzle," she said, which created a more complete model of a shape in space.
"This allows you to see how that overall constellation of points is changing from shape to shape," Vitek said. "You might see whole new patterns you would never have thought to measure before and capture things like curvature -- things that are really hard to measure in just a single linear feature.”
Her results showed that scientists on both sides of the debate are partially right.
The argument that modern variation in eastern box turtles mirrors variation in fossil specimens of the same species does have some merit.
"It's not like we hit the fossil record and there's a hard boundary between what's extinct and what still exists today," she said. "Just like we'd expect from evolution, there is a gradient of variation that carries through to modern box turtles. Having some shells that aren't that different is reassuring in the sense that, yes, some species do go back in time."
But, she added, some shells likely do belong to lost subspecies, existing subspecies or closely related extinct species.
"Some sites have shells that are not only bigger than modern eastern box turtles but also very different," she said. "There is lost variation in the eastern box turtle record. It turns out that if you go back to fossils, there is even more diversity than you would be able to pick up just by studying today's box turtles.”
Vitek said she is hopeful her study will spur more researchers to look deeper at bony structures within species as a means of detecting variation in fossils.
"We're doing a great job of seeing what drives patterns like mouse coat color, but let's also see what drives patterns in things like mouse teeth and arm bones," she said. "There's a lot of opportunity to start better documenting what the morphology we pick up in the fossil record might actually mean in terms of evolution."
Story Source:
Materials provided by Florida Museum of Natural History. Original written by Natalie van Hoose. Note: Content may be edited for style and length.
Journal Reference:
Natasha S. Vitek. Delineating modern variation from extinct morphology in the fossil record using shells of the Eastern Box Turtle (Terrapene carolina). PLOS ONE, 2018; 13 (3): e0193437 DOI: 10.1371/journal.pone.0193437
Ancient turtles: scientists find ancestor of modern sea turtles
ZME Science, 4/19/20 by Mihai Andrei
Paleontologists have found a new sea turtle species from the Cretaceous epoch which they believe to be an ancestor of all modern sea turtles.
pastedGraphic_4.png
This is a reconstruction of the new species (Peritresius martini). Image credits: Drew Gentry.
If you look at turtles today, it’s easy to guess that they’ve been around for a very long time. Like crocodiles and other reptiles, they had ancestors that lived alongside the dinosaurs in the Mesozoic times. Such an ancestor was Peritresius ornatus, who lived in North America during the Late Cretaceous epoch — from around 100 to 66 million years ago. Researchers thought that P. ornatus was the sole member of its group but now, a new study has found a sister species.
Named Peritresius martini after its discoverer, George Martin, the species was discovered based on fossils found in Alabama, US. Its shell measured over 90 cm long and 75 cm wide, which is far larger than known P. ornatus specimens. Researchers also note that the P. martini shell was rather plain, whereas the P. ornatus one had sculptured skin elements that were supported by blood vessels. This feature suggests that P. ornatus was capable of thermoregulation, self-regulating its body temperature based on the environmental conditions. This might have allowed it to keep warm and survive the global cooling that occurred throughout the Late Cretaceous, unlike most turtles, which went extinct.
“The heavily vascularized and sculptured dermal elements characteristic of P. ornatus are interpreted here as potentially indicative of a thermoregulatory capability and may have been one of the key factors contributing to the survival of Peritresius into the Maastrichtian, a period of cooling when other lineages of Campanian marine turtles (e.g., Protostegids, Toxochelys, and Ctenochelys) went extinct,” the study authors write.
The finding also shows that turtles belonging to this clade were far more widespread than previously believed. It’s unclear if other species belonging to the group existed.
Lead author Drew Gentry says:
“This discovery not only answers several important questions about the distribution and diversity of sea turtles during this period but also provides further evidence that Alabama is one of the best places in the world to study some of the earliest ancestors of modern sea turtles.”
Journal Reference: Gentry AD, Parham JF, Ehret DJ, Ebersole JA (2018) A new species of Peritresius Leidy, 1856 (Testudines: Pan-Cheloniidae) from the Late Cretaceous (Campanian) of Alabama, USA, and the occurrence of the genus within the Mississippi Embayment of North America. PLoS ONE 13(4): e0195651. https://doi.org/10.1371/journal.pone.0195651
ZME Science, 4/19/20 by Mihai Andrei
Paleontologists have found a new sea turtle species from the Cretaceous epoch which they believe to be an ancestor of all modern sea turtles.
pastedGraphic_4.png
This is a reconstruction of the new species (Peritresius martini). Image credits: Drew Gentry.
If you look at turtles today, it’s easy to guess that they’ve been around for a very long time. Like crocodiles and other reptiles, they had ancestors that lived alongside the dinosaurs in the Mesozoic times. Such an ancestor was Peritresius ornatus, who lived in North America during the Late Cretaceous epoch — from around 100 to 66 million years ago. Researchers thought that P. ornatus was the sole member of its group but now, a new study has found a sister species.
Named Peritresius martini after its discoverer, George Martin, the species was discovered based on fossils found in Alabama, US. Its shell measured over 90 cm long and 75 cm wide, which is far larger than known P. ornatus specimens. Researchers also note that the P. martini shell was rather plain, whereas the P. ornatus one had sculptured skin elements that were supported by blood vessels. This feature suggests that P. ornatus was capable of thermoregulation, self-regulating its body temperature based on the environmental conditions. This might have allowed it to keep warm and survive the global cooling that occurred throughout the Late Cretaceous, unlike most turtles, which went extinct.
“The heavily vascularized and sculptured dermal elements characteristic of P. ornatus are interpreted here as potentially indicative of a thermoregulatory capability and may have been one of the key factors contributing to the survival of Peritresius into the Maastrichtian, a period of cooling when other lineages of Campanian marine turtles (e.g., Protostegids, Toxochelys, and Ctenochelys) went extinct,” the study authors write.
The finding also shows that turtles belonging to this clade were far more widespread than previously believed. It’s unclear if other species belonging to the group existed.
Lead author Drew Gentry says:
“This discovery not only answers several important questions about the distribution and diversity of sea turtles during this period but also provides further evidence that Alabama is one of the best places in the world to study some of the earliest ancestors of modern sea turtles.”
Journal Reference: Gentry AD, Parham JF, Ehret DJ, Ebersole JA (2018) A new species of Peritresius Leidy, 1856 (Testudines: Pan-Cheloniidae) from the Late Cretaceous (Campanian) of Alabama, USA, and the occurrence of the genus within the Mississippi Embayment of North America. PLoS ONE 13(4): e0195651. https://doi.org/10.1371/journal.pone.0195651
