WFS

Formation of sedimentary layers of white clay, Tamilnadu, India

Fossil site for wood fossils, Tamilnadu, India

Fossil site in Kerala, India

Fossil wood park maintained by geological survey of India at Tamilnadu

Cretaceous fossil sites india

Fossils in rack:-Cyad

Fossils in rack:-echiniderms

Fossils in rack:-Rastellum sp

Pre-historic seabed, Cretaceous period

WFS News: EVIDENCE OF NEOTECTONIC ACTIVITY ALONG THE EAST COAST OF INDIAN PENINSULA

March 26th, 2018

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@WFS,World fossil Society,Riffin T Sajeev,Russel T Sajeev

EVIDENCE OF NEOTECTONIC ACTIVITY ALONG THE EAST COAST OF INDIAN PENINSULA ( Riffin T Sajeev

Geological Society of America Abstracts with Programs.doi: 10.1130/abs/2017AM-293786,Volume 49,Issue 6,Pages

388 T219. Challenges in Tectonics:Publisher:Geological Society of America (GSA) :https://gsa.confex.com/gsa/2017AM/meetingapp.cgi/Paper/293786

Abstract:

The eastern coastal plains of the Indian peninsula are studied meagerly based on its tectonic aspects. In the previous ventures, the author reported the paleochronological existence of a large estuary, on the basis of fossils of Crassostrea Sp. Dating back to the mio-pliocene Epoch. The author suggests that the paleo-estuary ceased in existence due to a marine regression caused by a regional uplift in between the present day trajectories of the rivers Thamirabharani and Nambiar. The natures of structural characteristics seen in the regional outcrops of the basin indicate a dominant neotectonic feature. Brittle slip faults are abundant in these rocky outcrops containing Khondalite beds. Shearing is visible almost anywhere. This may be caused by the near proximity of the study area with the Achankovil Shear Zone (AKSZ). A second look at the trajectories of the rivers and drainage mentioned above and the structural features on the outcrops indicate that the uplift is neotectonically induced rather than shear induced.During site exploration, the author found rocks of volcanic origin distributed randomly over the study area. Till this date, the geological community had approached volcanic/ neo tectonic activities in this area only through speculations without any physical, visible evidence. The presences of chunks of volcanic rocks are an acute visual evidence of an event of volcanic nature. Through this study, the author aims to analyze the extent of uplift and its impact on the drainage systems of the rivers on its either side and their divide migration possibilities. The neotectonic aspects of the region are analyzed and any solid evidence of active volcanism is collected and studied. The study is primarily aimed to report the existence of neotectonic activity in the south eastern coast of India.

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WFS facts: dating of fossils

March 21st, 2018

Riffin

Radioactive dating

For example if you have a fossil trilobite and it was found in the Wheeler Formation. The Wheeler Formation has been previously dated to approximately 507 million year old, so we know the trilobite is also about 507 million years old. But, how can we determine how old a rock formation is, if it hasn’t previously been dated?

Scientists can use certain types of fossils referred to as index fossils to assist in relative dating via correlation. Index fossils are fossils that are known to only occur within a very specific age range. Typically commonly occurring fossils that had a widespread geographic distribution such as brachiopods, trilobites, and ammonites work best as index fossils. If the fossil you are trying to date occurs alongside one of these index fossils, then the fossil you are dating must fall into the age range of the index fossil.

Sometimes multiple index fossils can be used. In a hypothetical example, a rock formation contains fossils of a type of brachiopod known to occur between 410 and 420 million years. The same rock formation also contains a type of trilobite that was known to live 415 to 425 million years ago. Since the rock formation contains both types of fossils the ago of the rock formation must be in the overlapping date range of 415 to 420 million years.

Studying the layers of rock or strata can also be useful. Layers of rock are deposited sequentially. If a layer of rock containing the fossil is higher up in the sequence that another layer, you know that layer must be younger in age. If it is lower in sequence it’s of a younger age. This can often be complicated by the fact that geological forces can cause faulting and tilting of rocks.

Absolute dating is used to determine a precise age of a rock or fossil through radiometric dating methods. This uses radioactive minerals that occur in rocks and fossils almost like a geological clock. It’s often much easier to date volcanic rocks than the fossils themselves or the sedimentary rocks they are found in. So, often layers of volcanic rocks above and below the layers containing fossils can be dated to provide a date range for the fossil containing rocks.

The atoms in some chemical elements have different forms, called isotopes. These isotopes break down at a constant rate over time through radioactive decay. By measuring the ratio of the amount of the original (parent) isotope to the amount of the (daughter) isotopes that it breaks down into an age can be determined.

We define the rate of this radioactive decay in half-lives. If a radioactive isotope is said to have a half-life of 5,000 years that means after 5,000 years exactly half of it will have decayed from the parent isotope into the daughter isotopes. Then after another 5,000 years half of the remaining parent isotope will have decayed.

While people are most familiar with carbon dating, carbon dating is rarely applicable to fossils. Carbon-14, the radioactive isotope of carbon used in carbon dating has a half-life of 5730 years, so it decays too fast. It can only be used to date fossils younger than about 75,000 years. Potassium-40 on the other hand has a half like of 1.25 billion years and is common in rocks and minerals. This makes it ideal for dating much older rocks and fossils.

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WFS News:60-year-old paleontological mystery of a ‘phantom’ dicynodont

March 20th, 2018

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@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

A new study has re-discovered fossil collections from a 19th century hermit that validate ‘phantom’ fossil footprints collected in the 1950s showing dicynodonts coexisting with dinosaurs.

Before the dinosaurs, around 260 million years ago, a group of early mammal relatives called dicynodonts were the most abundant vertebrate land animals. These bizarre plant-eaters with tusks and turtle-like beaks were thought to have gone extinct by the Late Triassic Period, 210 million years ago, when dinosaurs first started to proliferate. However, in the 1950s, suspiciously dicynodont-like footprints were found alongside dinosaur prints in southern Africa, suggesting the presence of a late-surviving phantom dicynodont unknown in the skeletal record. These “phantom” prints were so out-of-place that they were disregarded as evidence for dicynodont survival by paleontologists. A new study has re-discovered fossil collections from a 19th century hermit that validate these “phantom” prints and show that dicynodonts coexisted with early plant-eating dinosaurs. While this research enhances our knowledge of ancient ecosystems, it also emphasizes the often-overlooked importance of trace fossils, like footprints, and the work of amateur scientists.

This is a skeleton of the dicynodont Placerias, a close relative of the newly-discovered Pentasaurus, with dicynodont trackways (Pentasauropus).Credit: Christian Kammerer

“Although we tend to think of paleontological discoveries coming from new field work, many of our most important conclusions come from specimens already in museums,” says Dr. Christian Kammerer, Research Curator of Paleontology at the North Carolina Museum of Natural Sciences and author of the new study.

The re-discovered fossils that solved this mystery were originally collected in South Africa in the 1870s by Alfred “Gogga” Brown. Brown was an amateur paleontologist and hermit who spent years trying, with little success, to interest European researchers in his discoveries. Brown had shipped these specimens to the Natural History Museum in Vienna in 1876, where they were deposited in the museum’s collection but never described.

“I knew the Brown collections in Vienna were largely unstudied, but there was general agreement that his Late Triassic collections were made up only of dinosaur fossils. To my great surprise, I immediately noticed clear dicynodont jaw and arm bones among these supposed ‘dinosaur’ fossils,” says Kammerer. “As I went through this collection I found more and more bones matching a dicynodont instead of a dinosaur, representing parts of the skull, limbs, and spinal column.” This was exciting — despite over a century of extensive collection, no skeletal evidence of a dicynodont had ever been recognized in the Late Triassic of South Africa.

Before this point, the only evidence of dicynodonts in the southern African Late Triassic was from questionable footprints: a short-toed, five-fingered track named Pentasauropus incredibilis (meaning the “incredible five-toed lizard foot”). In recognition of the importance of these tracks for suggesting the existence of Late Triassic dicynodonts and the contributions of “Gogga” Brown in collecting the actual fossil bones, the re-discovered and newly described dicynodont has been named Pentasaurus goggai (“Gogga’s five-[toed] lizard”).

“The case of Pentasaurus illustrates the importance of various underappreciated sources of data in understanding prehistory,” says Kammerer. “You have the contributions of amateur researchers like ‘Gogga’ Brown, who was largely ignored in his 19th century heyday, the evidence from footprints, which some paleontologists disbelieved because they conflicted with the skeletal evidence, and of course the importance of well-curated museum collections that provide scientists today an opportunity to study specimens collected 140 years ago.”

A video about this new research can be found here: https://savetubevideo.com/?v=BrdwIQKPCHY

Journal reference:Christian F. Kammerer. The first skeletal evidence of a dicynodont from the lower Elliot Formation of South Africa. Palaeontologia Africana, 2018

North Carolina Museum of Natural Sciences. “60-year-old paleontological mystery of a ‘phantom’ dicynodont.” ScienceDaily. ScienceDaily, 14 March 2018. <www.sciencedaily.com/releases/2018/03/180314092330.htm>.

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Five New Fossil Forests Found in Antarctica

March 18th, 2018

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Antarctica is one of the harshest environments on the planet. As the coldest, driest continent, it harbors a world of extremes. The powerful katabatic winds that rush from the polar plateau down the steep, vertical drops around the continent’s coast can stir up turbulent snowstorms lasting days or weeks, and the endlessly barren terrain gives Antarctica the title of the world’s largest desert.

Today, polar summers pound the continent with 24 unforgiving hours of light for about half the year, before polar winters plunge it into complete darkness for the other half. Regardless of the season, the temperatures are consistently below freezing, making treks to the landmass unthinkable for the faint of heart.

Scientist Patricia Ryberg returns to Graphite Peak camp after a day collecting fossils on nearby outcrops of rock. The team spent nine days here, living in small mountain tents, and exploring the surrounding terrain between storms.PHOTOGRAPH BY DANNY UHLMANN

But Antarctica wasn’t always like this. Hundreds of millions of years ago, the continent was smushed together with other modern-day landmasses to form the supercontinent Gondwana. Gondwana was humid and carpeted with a network of hardy plants. As the turbulent climate shifted from hot to cold on a sometimes monthly basis, the streamlined foliage would have needed to withstand extremes.

But then, a massive extinction event pulsed through the land. It catapulted nearly all life to an end, obliterating more than 90 percent of the world’s species at the time.

On the flanks of Graphite Peak, Rudolph Serbet uncovers a 250 million- year-old fossilized tree stump.PHOTOGRAPH BY DANNY UHLMANN

What caused this die-off, called the Permian extinction or the Great Dying, is still shrouded in mystery. Clues to the massacre come to us in the form of fossilized trees, but much of the reasons behind this extinction remain unsolved. And that’s why a handful of intrepid scientists traveled to Antarctica this winter, curious to uncover clues about what led to the end of the continent’s forested past.

“Our goal this year was to study fossil ecosystems around the time of the late Permian,” says Erik Gulbranson, a University of Wisconsin-Milwaukee professor who was one of three team leaders on an expedition to the continent in late 2017. “What we’re able to see in these fossil ecosystems is something we’ve never seen before in Antarctica.”

A fallen, fossilized log sits entombed in a bed of sandstone on the flanks of Graphite Peak.
PHOTOGRAPH BY DANNY UHLMANN

“These new findings tell us how these organisms were reacting or responding to the climatic or environmental changes that were taking place during the extinction crisis,” Gulbranson says. “Having a fossil record of the extinction interval is our only understanding of how life on the planet goes through such an event.”

This work is timely, since many scientists warn that we’re going through an extinction period right now, spurred by human disruptions to natural systems.

MAKING THE TREK

What we know about the Permian extinction we know through marine fossils of animals that once lived in the oceans. Many scientists agree that during this period about 299 to 251 million years ago, a volcanic eventtriggered a crisis that exterminated about 90 percent of all species on the planet. It eradicated more than 95 percent of marine species and more than 70 percent of all land species.

But beyond the broad outlines, a number of the details are unclear. Some geologists and paleontologists say the Permian extinction occurred over 15 million years, but others say it lasted 20,000 years—a blink of an eye in the scheme of geologic time.

The team that Gulbranson, along with his colleague John Isbell and the University of Kansas’s Rudolf Serbit, put together has diverse skillsets. There’s Park University biology professor Patricia Ryberg, who studies the anatomy and morphology of paleobotany, or fossilized plants. There’s also Brian Atkinson, a postdoctoral researcher at the University of Kansas who focuses on seed plants from the Cretaceous period, which is after the Permian. Whereas Ryberg had been on three Antarctic expeditions with Gulbranson, Atkinson had never been to Antarctica before. In fact, this was the second time he had camped out in his life.

“Going to Antarctica is like going to another planet,” Atkinson says. “When you’re searching for plant fossils, it’s like traveling through time. This is as exotic as it gets.”

Gulbranson says this expedition was easily one of the most significant and productive field seasons the team has had to date. At the end of November, the seven-person team left for Antarctica. By early December, they flew a Lockheed LC-130 military aircraft to the Shackleton and McGregor glaciers in the middle of the continent. They pitched two camps, setting up one as a base. For the duration of the 21-day trip, they flew between the two sites by helicopter.

“Those [helicopter] blades are one of the scariest things that you can experience up close,” says Atkinson. The scientists had to constantly jump in and out of choppers—whose thumping blades could slice off a limb in a split second. With the closest hospital thousands of miles away, they had to be cautious coming in and out of the aircraft.

NEW FOSSIL FORESTS

Thirty-mile-per-hour winds pounded the team for days, sometimes lasting up to 12 hours at a time. As they were studying rocks and hiking the first camp, the team discovered five new fossil forests that no one knew existed on the continent. They found some fossil remnants at the second site, but nothing as significant as their findings at the first.

The fossilized trees look a lot like the petrified forests of Yellowstone National Park. Before this expedition, science wasn’t sure if the Permian interval was preserved in sedimentary rocks in Antarctica, but the expedition members think the sedimentary succession they discovered happened at the same time as the extinction interval. That means these new fossil forests would have lived into and beyond the extinction event, representing three distinct ecologic niches from 251 million years ago.

This connection between plants and ecosystems during the extinction event hasn’t been seen until now. The team hopes the discovery can give some clues as to how the Permian extinction played out on land. Ancient microbial life may have played an important role, the team suspects.

“I’m trying to put a puzzle together, but I have no reference picture to do it,” Ryberg says.

PUSHING UP PETRIFIED PLANTS

Permian-era plants are like nothing alive today, Ryberg says. She studies a group of foliage in the genus Glossopteris, which is characterized by woody plants dated roughly 300 to 200 million years ago. The fossil record tells us that Glossopteris plants commonly had tongue-shaped leaves found in thick mats, leading scientists to think they were deciduous.

“Plants are so weird,” Atkinson adds. “There’s a whole lot of different morphologies that you just don’t see in modern plants. The more we get to know these plants, the more weird they become.”

By studying such past changes, scientists hope to get more windows onto the future. There’s time pressure, because conservationists warn that in about 300 years, 75 percent of all mammal species may have disappeared from the planet. By 2060, some say we could see 30 percent of all species go extinct. Whereas other extinction events have been triggered by natural causes, the one we may be in is likely driven by habitat destruction, climate change, and pollution, among other factors.

The Permian extinction may teach us how species react—and adapt—to extinction, Gulbranson says.

For as long as mysteries such as the Great Dying remain, curious scientists will be trekking to remote locations to learn about our planet’s past. This kind of research takes scientific know-how, endurance, and—perhaps most of all—curiosity.

“There’s a certain type of badassness that is required for scientists who want to go to a remote camp in the middle of Antarctica to collect fossils and rock data,” Atkinson says. “I have to go back.”

Source and article : By Elaina Zachos and Photographs by Danny Uhlmann

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WFS News: Unique diamond impurities indicate water deep in Earth’s mantle

March 14th, 2018

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@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

A UNLV scientist has discovered the first direct evidence that fluid water pockets may exist as far as 500 miles deep into the Earth’s mantle.

Groundbreaking research by UNLV geoscientist Oliver Tschauner and colleagues found diamonds pushed up from the Earth’s interior had traces of unique crystallized water called Ice-VII.

The study, “Ice-VII inclusions in Diamonds: Evidence for aqueous fluid in Earth’s deep Mantle,” was published Thursday in the journal Science.

Rough diamond in kimberlite. (stock image) Credit: © Kacpura / Fotolia

In the jewelry business, diamonds with impurities hold less value. But for Tschauner and other scientists, those impurities, known as inclusions have infinite value, as they may hold the key to understanding the inner workings of our planet.

For his study, Tschauner used diamonds found in China, the Republic of South Africa, and Botswana that surged up from inside Earth. “This shows that this is a global phenomenon,” the professor said.

Scientists theorize the diamonds used in the study, were born in the mantle under temperatures reaching more than 1,000-degrees Fahrenheit.

The mantle — which makes up more than 80 percent of the Earth’s volume — is made of silicate minerals containing iron, aluminum, and calcium among others.

And now we can add water to the list.

The discovery of Ice-VII in the diamonds is the first known natural occurrence of the aqueous fluid from the deep mantle. Ice-VII had been found in prior lab testing of materials under intense pressure. Tschauner also found that while under the confines of hardened diamonds found on the surface of the planet, Ice-VII is solid. But in the mantel, it is liquid.

“These discoveries are important in understanding that water-rich regions in the Earth’s interior can play a role in the global water budget and the movement of heat-generating radioactive elements,” Tschauner said.

This discovery can help scientists create new, more accurate models of what’s going on inside the Earth, specifically how and where heat is generated under the Earth’s crust.

In other words: “It’s another piece of the puzzle in understanding how our planet works,” Tschauner said.

Of course, as it often goes with discoveries, this one was found by accident, explained Tschauner.

“We were looking for carbon dioxide,” he said. “We’re still looking for it, actually,”

O. Tschauner, S. Huang, E. Greenberg, V. B. Prakapenka, C. Ma, G. R. Rossman, A. H. Shen, D. Zhang, M. Newville, A. Lanzirotti, K. Tait. Ice-VII inclusions in diamonds: Evidence for aqueous fluid in Earth’s deep mantle. Science, 2018; 359 (6380): 1136 DOI: 10.1126/science.aao3030

University of Nevada, Las Vegas. “Unique diamond impurities indicate water deep in Earth’s mantle: Scientific analysis of diamond impurities — known as inclusions — reveal naturally forming ice crystals and point to water-rich regions deep below the Earth’s crust.” ScienceDaily. ScienceDaily, 9 March 2018. <www.sciencedaily.com/releases/2018/03/180309170700.htm>

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WFS News: Half-Billion-Year-Old Fossil Brains Found in Ancient Predator (Kerygmachela kierkegaardi)

March 12th, 2018

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@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

An artist’s reconstruction of the 520-million-year-old Kerygmachela kierkegaardi depicts the ancient species as a formidable ocean predator. ILLUSTRATION BY REBECCA GELERNTER, NEARBIRD STUDIOS

With help from 15 fossils recently discovered in Greenland, scientists are now able to peer inside the brain of an animal that lived 520 million years ago.

The extinct species, Kerygmachela kierkegaardi, swam in ocean waters during an evolutionary arms race called the Cambrian explosion. Flanked by 11 wrinkly flaps on each side of its body, the ancient predator sported a long tail spine and a rounded head. Its fearsome forward-facing appendages grasped prey, says UK-based paleontologist Jakob Vinther, “making lives miserable for other animals.”

Previous fossil remains of the roughly one- to ten-inch creature came from loose rocks battered by weather. But the new finds are the species’ first to escape exposure to the elements, resulting in fossil nervous tissue that is providing new evolutionary insights into the brains of panarthropods—an animal group that includes water bears (tardigrades), velvet worms, and arthropods like crustaceans and insects.

The study, led by Vinther and the Korea Polar Research Institute‘s Tae-Yoon Park, was published March 9 in the journal Nature Communications.

Contradicting some previous accounts, the team argues that this new evidence appears to show that the common ancestor of all panarthropods did not have a complex three-part brain—and neither did the common ancestor of invertebrate panarthropods and vertebrates.

Modern arthropods begin developing with a single bundle of nerve cells above their gut. They bear two other brain segments, lying beside or beneath the gut, which migrate up during development to fuse with the first nerve bundle, forming an intricate, triple-segmented brain.

That structure can be traced back through the fossil record. Kerygmachela’s relatively simple brain, preserved as thin films of carbon, includes only the foremost of the three segments present in living arthropods.

The team believes that water bears, the eight-legged micro-critters known formally as tardigrades, have a simple one-segment brain similar to what they identify in Karygmachela. Velvet worms—soft-bodied, nocturnal ambush predators—also lack a three-part brain.

A HALF-BILLION-YEAR-OLD BRAINA well-preserved Kerygmachela fossil from Greenland (left) contains identifiable nervous system tissue in the head (closeup, right). This new evidence suggests that the common ancestor of all panarthropods lacked a complex brain. PHOTOGRAPH BY TAE YOON PARK, KOPRI

A HALF-BILLION-YEAR-OLD BRAINA well-preserved Kerygmachela fossil from Greenland contains identifiable nervous system tissue in the head. This new evidence suggests that the common ancestor of all panarthropods lacked a complex brain.
PHOTOGRAPH BY TAE YOON PARK, KOPRI

So it makes sense to think that the common ancestor these animals share with arthropods also lacked a complex brain. Ditto for the organism that gave rise to both panarthropods and vertebrates, the other animal group whose brains have three segments.

Not all scientists are convinced of the details. Tardigrade brains may or may not develop based on segments at all, says Nicholas Strausfeld, a neuroscientist at the University of Arizona who was not involved in the study.

“If they’re going to say that the brain of Kerygmachela is like that of a tardigrade, you have to be really, really careful,” Strausfeld warns. “Because it might not be.” Tardigrades may lack a segmental brain altogether, instead relying on a ring of nerves around their mouths.

Vinther finds that perspective interesting. Whatever the case, he says, both ideas point to simpler ancestral nervous systems—and thus an evolutionary history in which animals’ brains evolved complex three-part structures multiple independent times.

The competition driving evolutionary arms races, Vinther says, “has led to similar outcomes that we see in different groups: eyes, complex brains, and so forth.”

Source: Article By Andrew Urevig,National Geographic

WFS News: Caudal autotomy as anti-predatory behaviour in Palaeozoic reptiles

March 9th, 2018

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Imagine that you’re a voracious carnivore who sinks its teeth into the tail of a small reptile and anticipates a delicious lunch, when, in a flash, the reptile is gone and you are left holding a wiggling tail between your jaws.

A new study by the University of Toronto Mississauga research team led by Professor Robert Reisz and PhD student Aaron LeBlanc, published March 5 in the open source journal, Scientific Reports, shows how a group of small reptiles who lived 289 million years ago could detach their tails to escape the grasp of their would-be predators — the oldest known example of such behaviour. The reptiles, called Captorhinus, weighed less than 2 kilograms and were smaller than the predators of the time. They were abundant in terrestrial communities during the Early Permian period and are distant relatives of all the reptiles today.

$Fracture planes in captorhinid caudal vertebrae. (a) Artist’s reconstruction of the Permian reptile Captorhinus with an autotomous tail (inset showing anterior caudal vertebrae with fracture planes). (b) Image and (c) SEM image of an isolated anterior caudal vertebra (ROM 73769) with a fracture plane passing through the centrum (black arrow). (d) Ventral view of an anterior, rib-bearing caudal vertebra (ROM 77410) showing the absence of any fracture plane. (e) Ventral view of a caudal vertebra bearing a fracture plane (black arrows) (ROM 73771) (f) thin-section through the sagittal plane of a caudal vertebra (ROM 73773) with a fracture plane (black arrow) passing through the ventral portion of the centrum. (g) Close-up of fracture plane (black arrows) in (f) passing into the notochordal canal. Abbreviations: cb, cortical bone; cct, calcified cartilage; ce, centrum; nc, neural canal; ns, neural spine; ntc, notochordal canal. Reconstruction by Danielle Dufault. Anterior is to the left in all of the images.$

Fracture planes in captorhinid caudal vertebrae. (a) Artist’s reconstruction of the Permian reptile Captorhinus with an autotomous tail (inset showing anterior caudal vertebrae with fracture planes). (b) Image and (c) SEM image of an isolated anterior caudal vertebra (ROM 73769) with a fracture plane passing through the centrum (black arrow). (d) Ventral view of an anterior, rib-bearing caudal vertebra (ROM 77410) showing the absence of any fracture plane. (e) Ventral view of a caudal vertebra bearing a fracture plane (black arrows) (ROM 73771) (f) thin-section through the sagittal plane of a caudal vertebra (ROM 73773) with a fracture plane (black arrow) passing through the ventral portion of the centrum. (g) Close-up of fracture plane (black arrows) in (f) passing into the notochordal canal. Abbreviations: cb, cortical bone; cct, calcified cartilage; ce, centrum; nc, neural canal; ns, neural spine; ntc, notochordal canal. Reconstruction by Danielle Dufault. Anterior is to the left in all of the images.

As small omnivores and herbivores, Captorhinus and its relatives had to scrounge for food while avoiding being preyed upon by large meat-eating amphibians and ancient relatives of mammals. “One of the ways captorhinids could do this,” says first author LeBlanc, “was by having breakable tail vertebrae.” Like many present-day lizard species, such as skinks, that can detach their tails to escape or distract a predator, the middle of many tail vertebrae had cracks in them.

$Serial transverse sections through the centra of fracture plane-bearing caudal vertebrae in captorhinids. (a) Transverse section taken near the base of the centrum (ROM 73771); (b) Closeup of the fracture plane running across the ventral surface of the centrum in (a). (c) Transverse section taken at the level of the notochordal canal (ROM 73774). (d) Closeup of the fracture plane in c passing through the centrum into the notochordal canal. (e) Transverse section taken along the roof of the centrum (below the neural arch) (ROM 73774). (f) Closeup of fracture plane in (g) passing through the outer cortical bone, but not the more internal endosteal/endochondral bone. Abbreviations: cb, cortical bone; eb, endochondral bone; rl, reversal line; sf, Sharpey’s fibers. Anterior is to the left in all of the images.$

Serial transverse sections through the centra of fracture plane-bearing caudal vertebrae in captorhinids. (a) Transverse section taken near the base of the centrum (ROM 73771); (b) Closeup of the fracture plane running across the ventral surface of the centrum in (a). (c) Transverse section taken at the level of the notochordal canal (ROM 73774). (d) Closeup of the fracture plane in c passing through the centrum into the notochordal canal. (e) Transverse section taken along the roof of the centrum (below the neural arch) (ROM 73774). (f) Closeup of fracture plane in (g) passing through the outer cortical bone, but not the more internal endosteal/endochondral bone. Abbreviations: cb, cortical bone; eb, endochondral bone; rl, reversal line; sf, Sharpey’s fibers. Anterior is to the left in all of the images.

It is likely that these cracks acted like the perforated lines between two paper towel sheets, allowing vertebrae to break in half along planes of weakness. “If a predator grabbed hold of one of these reptiles, the vertebra would break at the crack and the tail would drop off, allowing the captorhinid to escape relatively unharmed,” says Reisz, a Distinguished Professor of Biology at the University of Toronto Mississauga.

The authors note that being the only reptiles with such an escape strategy may have been a key to their success, because they were the most common reptiles of their time, and by the end of the Permian period 251 million years ago, captorhinids had dispersed across the ancient supercontinent of Pangaea. This trait disappeared from the fossil record when Captorhinus died out; it re-evolved in lizards only 70 million years ago.

$Hypothesized path of autotomy break in the caudal centra of captorhinids. (a–c) Lateral, anterior, and ventral views of a fracture plane-bearing caudal centrum, showing the extend of the fracture plane, which does not pass through the neural arch or spine (ROM 73774). (d,e) SEM images of a post mortem break in a captorhinid caudal vertebra (ROM 77409) along its fracture plane. The break follows the plane of weakness formed by the autotomy plane (white arrow) and is found on the left (d) and right (e) sides, suggesting that this was the plane of weakness in life. (f) Reconstruction of caudal autotomy in a caudal vertebra. During autotomy, the fracture follows the path of least resistance through the dorsal half of the caudal centrum and the posterior base of the neural arch, bypassing the neural spine. Abbreviation: na, neural arch; nc, neural canal; ns, neural spine; ntc, notochordal canal. Anterior is to the left in all of the images.$

Hypothesized path of autotomy break in the caudal centra of captorhinids. (a–c) Lateral, anterior, and ventral views of a fracture plane-bearing caudal centrum, showing the extend of the fracture plane, which does not pass through the neural arch or spine (ROM 73774). (d,e) SEM images of a post mortem break in a captorhinid caudal vertebra (ROM 77409) along its fracture plane. The break follows the plane of weakness formed by the autotomy plane (white arrow) and is found on the left (d) and right (e) sides, suggesting that this was the plane of weakness in life. (f) Reconstruction of caudal autotomy in a caudal vertebra. During autotomy, the fracture follows the path of least resistance through the dorsal half of the caudal centrum and the posterior base of the neural arch, bypassing the neural spine. Abbreviation: na, neural arch; nc, neural canal; ns, neural spine; ntc, notochordal canal. Anterior is to the left in all of the images.

They were able to examine more than 70 tail vertebrae — both juveniles and adults — and partial tail skeletons with splits that ran through their vertebrae. They compared these skeletons to those of other reptilian relatives of captorhinids, but it appears that this ability is restricted to this family of reptiles in the Permian period.

Using various paleontological and histological techniques, the authors discovered that the cracks were features that formed naturally as the vertebrae were developing. Interestingly, the research team found that young captorhinids had well-formed cracks, while those in some adults tended to fuse up. This makes sense, since predation is much greater on young individuals and they need this ability to defend themselves.

This study was possible thanks to the treasure trove of fossils available at the cave deposits near Richards Spur, Oklahoma.

A. R. H. LeBlanc, M. J. MacDougall, Y. Haridy, D. Scott, R. R. Reisz. Caudal autotomy as anti-predatory behaviour in Palaeozoic reptiles. Scientific Reports, 2018; 8 (1) DOI: 10.1038/s41598-018-21526-3

University of Toronto. “Ancient reptile Captorhinus could detach its tail to escape predator’s grasp.” ScienceDaily. ScienceDaily, 6 March 2018. <www.sciencedaily.com/releases/2018/03/180306115741.htm>.

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Baby bird fossil ( Enantiornithes) gives a rare look at avian development

March 8th, 2018

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@ WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

The tiny fossil of a prehistoric baby bird is helping scientists understand how early avians came into the world in the Age of Dinosaurs.

The fossil, which dates back to the Mesozoic Era (250-65 million years ago), is a chick from a group of prehistoric birds called, Enantiornithes. Made up of a nearly complete skeleton, the specimen is amongst the smallest known Mesozoic avian fossils ever discovered.

TINY FOSSIL The breastbone of this fossilized ancient baby bird was still mostly cartilage, rather than bone, when the bird died, meaning it wouldn’t yet have been able to fly,an analysis suggests.

It measures less than five centimetres — smaller than the little finger on an average human hand — and would have weighed just three ounces when it was alive. What makes this fossil so important and unique is the fact it died not long after its birth. This is a critical stage in a bird’s skeletal formation. That means this bird’s extremely short life has given researchers a rare chance to analyse the species’ bone structure and development.

LANDLOCKED A baby Enantiornithes, which might have looked like this artist’s illustration, was born about 127 million years ago. The hatchling would have been less than 5 centimeters in length, roughly the size of a large cockroach.

Studying and analysing ossification — the process of bone development — can explain a lot about a young bird’s life the researchers say. It can help them understand everything from whether it could fly or if it needed to stay with its parents after hatching or could survive on its own.

The lead author of the study, Fabien Knoll, from The University of Manchester’s Interdisciplinary Centre for Ancient Life (ICAL), School of Earth and Environmental Sciences, and the ARAID — Dinopolis in Spain explains: ‘The evolutionary diversification of birds has resulted in a wide range of hatchling developmental strategies and important differences in their growth rates. By analysing bone development we can look at a whole host of evolutionary traits.’

With the fossil being so small the team used synchrotron radiation to picture the tiny specimen at a ‘submicron’ level, observing the bones’ microstructures in extreme detail.

Knoll said: ‘New technologies are offering palaeontologists unprecedented capacities to investigate provocative fossils. Here we made the most of state-of-the-art facilities worldwide including three different synchrotrons in France, the UK and the United States.’

The researchers found the baby bird’s sternum (breastplate bone) was still largely made of cartilage and had not yet developed into hard, solid bone when it died, meaning it wouldn’t have been able to fly.

Phosphorous mapping image and photo of fossil.Credit: Dr. Fabien Knoll

The patterns of ossification observed in this and the other few very young enantiornithine birds known to date also suggest that the developmental strategies of this particular group of ancient avians may have been more diverse than previously thought.

However, the team say that its lack of bone development doesn’t necessarily mean the hatchling was over reliant on its parents for care and feeding, a trait known as being ‘altricial’. Modern day species like love birds are highly dependent on their parents when born. Others, like chickens, are highly independent, which is known as ‘precocial’. Although, this is not a black-and-white issue, but rather a spectrum, hence the difficulty in clarifying the developmental strategies of long gone bird species.

Luis Chiappe, from the LA Museum of Natural History and study’s co-author added: ‘This new discovery, together with others from around the world, allows us to peek into the world of ancient birds that lived during the age of dinosaurs. It is amazing to realise how many of the features we see among living birds had already been developed more than 100 million years ago.’

Fabien Knoll, Luis M. Chiappe, Sophie Sanchez, Russell J. Garwood, Nicholas P. Edwards, Roy A. Wogelius, William I. Sellers, Phillip L. Manning, Francisco Ortega, Francisco J. Serrano, Jesús Marugán-Lobón, Elena Cuesta, Fernando Escaso, Jose Luis Sanz. A diminutive perinate European Enantiornithes reveals an asynchronous ossification pattern in early birds. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-03295-9

University of Manchester. “127-million-year-old baby bird fossil sheds light on avian evolution.” ScienceDaily. ScienceDaily, 5 March 2018. <www.sciencedaily.com/releases/2018/03/180305093012.htm>.

@ WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Tiny bubbles of oxygen got trapped 1.6 billion years ago

March 4th, 2018

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@ WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Take a good look at this photo: It shows you 1.6 billion years old fossilized oxygen bubbles, created by tiny microbes in what was once a shallow sea somewhere on young Earth.

The bubbles were photographed and analyzed by researchers studying early life on Earth.

Microbes are of special interest: They were not only the first life forms on Earth. They also turned our planet into a tolerable environment for plants and animals and thus their activity paved the way for life as we know it today.

Fossilized bubbles and cyanobacterial fabric from 1.6 billion-year-old phosphatized microbial mats from Vindhyan Supergroup, central India. Credit: Stefan Bengtson.
Credit: Stefan Bengtson

Some of these early microbes were cyanobacteria that thrived in early shallow waters. They produced oxygen by photosynthesis, and sometimes the oxygen got trapped as bubbles within sticky microbial mats.

Fossilized bubbles and cyanobacterial fabric from 1.6 billion-year-old phosphatized microbial mats from Vindhyan Supergroup, central India. Credit Stefan Bengtson.

The bubbles in the photo were preserved, and today they can be seen as a signature for life.

Ph.D. Therese Sallstedt and colleagues from University of Southern Denmark, Swedish Museum of Natural History and Stockholm University studied fossilized sediments from India, and they found round spheres in the microbial mats.

We interpret them as oxygen bubbles created in cyanobacterial biomats in shallow waters 1,6 billion years ago, said Therese Sallstedt.

Cyanobacteria changed the face of the Earth irreversibly since they were responsible for oxygenating the atmosphere. Simultaneously they constructed sedimentary structures called stromatolites, which still exist on Earth today.

The researchers now think that cyanobacteria played a larger role than previously believed in creating phosphorites in shallow waters, thereby allowing today’s scientists a unique window into ancient ecosystems. They published their findings in the journal Geobiology.

T. Sallstedt, S. Bengtson, C. Broman, P. M. Crill, D. E. Canfield. Evidence of oxygenic phototrophy in ancient phosphatic stromatolites from the Paleoproterozoic Vindhyan and Aravalli Supergroups, India. Geobiology, 2018; 16 (2): 139 DOI: 10.1111/gbi.12274

University of Southern Denmark. “Tiny bubbles of oxygen got trapped 1.6 billion years ago.” ScienceDaily. ScienceDaily, 2 March 2018. <www.sciencedaily.com/releases/2018/03/180302101801.htm>.

@ WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Complete genomes of extinct and living elephants sequenced

March 3rd, 2018

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@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

An international team of researchers has produced one of the most comprehensive evolutionary pictures to date by looking at one of the world’s most iconic animal families — namely elephants, and their relatives mammoths and mastodons-spanning millions of years.

The team of scientists-which included researchers from McMaster, the Broad Institute of MIT and Harvard, Harvard Medical School, Uppsala University, and the University of Potsdam-meticulously sequenced 14 genomes from several species: both living and extinct species from Asia and Africa, two American mastodons, a 120,000-year-old straight-tusked elephant, and a Columbian mammoth.

This is crushed dentine from a Woolly Mammoth for DNA extraction. Credit: JD Howell, McMaster University

The study, published in the Proceedings of the National Academy of Science, sheds light on what scientists call a very complicated history, characterized by widespread interbreeding. They caution, however, the behaviour has virtually stopped among living elephants, adding to growing fears about the future of the few species that remain on earth.

“Interbreeding may help explain why mammoths were so successful over such diverse environments and for such a long time, importantly this genomic data also tells us that biology is messy and that evolution doesn’t happen in an organized, linear fashion,” says evolutionary geneticist Hendrik Poinar, one of the senior authors on the paper and Director of the McMaster Ancient DNA Centre and principal investigator at the Michael G. DeGroote Institute for Infectious Research.

“The combined analysis of genome-wide data from all these ancient elephants and mastodons has raised the curtain on elephant population history, revealing complexity that we were simply not aware of before,” he says.

A detailed DNA analysis of the ancient straight-tusked elephant, for example, showed that it was a hybrid with portions of its genetic makeup stemming from an ancient African elephant, the woolly mammoth and present-day forest elephants.

“This is one of the oldest high-quality genomes that currently exists for any species,” said Michael Hofreiter at the University of Potsdam in Germany, a co-senior author who led the work on the straight-tusked elephant.

Researchers also found further evidence of interbreeding among the Columbian and woolly mammoths, which was first reported by Poinar and his team in 2011. Despite their vastly different habitats and sizes, researchers believe the woolly mammoths, encountered Columbians mammoths at the boundary of glacial and in the more temperate ecotones of North America.

Strikingly, scientists found no genetic evidence of interbreeding among two of the world’s three remaining species, the forest and savanna elephants, suggesting they have lived in near-complete isolation for the past 500,000 years, despite living in neighbouring habitats.

“There’s been a simmering debate in the conservation communities about whether African savannah and forest elephants are two different species,” said David Reich, another co-senior author at the Broad Institute who is also a professor at the Department of Genetics at Harvard Medical School (HMS) and a Howard Hughes Medical Institute Investigator. “Our data show that these two species have been isolated for long periods of time — making each worthy of independent conservation status.”

Interbreeding among closely related mammals is fairly common, say researchers, who point to examples of brown and polar bears, Sumatran and Bornean orangutans, and the Eurasian gold jackal and grey wolves. A species can be defined as a group of similar animals that can successfully breed and produce fertile offspring.

“This paper, the product of a grand initiative we started more than a decade ago, is far more than just the formal report of the elephant genome. It will be a reference point for understanding how diverse elephants are related to each other and it will be a model for how similar studies can be done in other species groups,” said co-senior author Kerstin Lindblad-Toh, a senior associate member of the Broad Institute and Director of the Science for Life Laboratory at Uppsala University in Sweden.

“The findings were extremely surprising to us,” says Eleftheria Palkopoulou, a post-doctoral scientist in at HMS. “The elephant population relationships could not be explained by simple splits, providing clues for understanding the evolution of these iconic species.”

Researchers suggest that future work should explore whether the introduction of new genetic lineages into elephant populations-both living and ancient-played an important role in their evolution, allowing them to adapt to new habitats and fluctuating climates.

Eleftheria Palkopoulou, Mark Lipson, Swapan Mallick, Svend Nielsen, Nadin Rohland, Sina Baleka, Emil Karpinski, Atma M. Ivancevic, Thu-Hien To, R. Daniel Kortschak, Joy M. Raison, Zhipeng Qu, Tat-Jun Chin, Kurt W. Alt, Stefan Claesson, Love Dalén, Ross D. E. MacPhee, Harald Meller, Alfred L. Roca, Oliver A. Ryder, David Heiman, Sarah Young, Matthew Breen, Christina Williams, Bronwen L. Aken, Magali Ruffier, Elinor Karlsson, Jeremy Johnson, Federica Di Palma, Jessica Alfoldi, David L. Adelson, Thomas Mailund, Kasper Munch, Kerstin Lindblad-Toh, Michael Hofreiter, Hendrik Poinar, David Reich. A comprehensive genomic history of extinct and living elephants. Proceedings of the National Academy of Sciences, 2018; 201720554 DOI: 10.1073/pnas.1720554115

McMaster University. “Complete genomes of extinct and living elephants sequenced: Findings point to highly complex relationships.” ScienceDaily. ScienceDaily, 26 February 2018. <www.sciencedaily.com/releases/2018/02/180226152725.htm>.

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Formation of sedimentary layers of white clay, Tamilnadu, India

Fossil site for wood fossils, Tamilnadu, India

Fossil site in Kerala, India

Fossil site in Kerala, India

Fossil wood park maintained by geological survey of India at Tamilnadu

Cretaceous fossil sites india

Fossils in rack:-Cyad

Fossils in rack:-echiniderms

Fossils in rack:-Rastellum sp

Pre-historic seabed, Cretaceous period

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WFS News: Caudal autotomy as anti-predatory behaviour in Palaeozoic reptiles

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WFS News: Tiny bubbles of oxygen got trapped 1.6 billion years ago

WFS News: Complete genomes of extinct and living elephants sequenced

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