WFS news: Dinosaur parasites trapped in 100-million-year-old amber tell blood-sucking story

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Fossilised ticks discovered trapped and preserved in amber show that these parasites sucked the blood of feathered dinosaurs almost 100 million years ago, according to a new article published in Nature Communications today.

Sealed inside a piece of 99 million-year-old Burmese amber researchers found a so-called hard tick grasping a feather. The discovery is remarkable because fossils of parasitic, blood-feeding creatures directly associated with remains of their host are exceedingly scarce, and the new specimen is the oldest known to date.

The scenario may echo the famous mosquito-in-amber premise of Jurassic Park, although the newly-discovered tick dates from the Cretaceous period (145-66 million years ago) and will not be yielding any dinosaur-building DNA: all attempts to extract DNA from amber specimens have proven unsuccessful due to the short life of this complex molecule.

Hard tick grasping a dinosaur feather preserved in 99 million-year-old Burmese amber. Modified from the open access article published in Nature Communications: 'Ticks parasitised feathered dinosaurs as revealed by Cretaceous amber assemblages.' Credit: Paper authors.

Hard tick grasping a dinosaur feather preserved in 99 million-year-old Burmese amber. Modified from the open access article published in Nature Communications: ‘Ticks parasitised feathered dinosaurs as revealed by Cretaceous amber assemblages.’Credit: Paper authors.

“Ticks are infamous blood-sucking, parasitic organisms, having a tremendous impact on the health of humans, livestock, pets, and even wildlife, but until now clear evidence of their role in deep time has been lacking,” says Enrique Peñalver from the Spanish Geological Survey (IGME) and leading author of the work.

Cretaceous amber provides a window into the world of the feathered dinosaurs, some of which evolved into modern-day birds. The studied amber feather with the grasping tick is similar in structure to modern-day bird feathers, and it offers the first direct evidence of an early parasite-host relationship between ticks and feathered dinosaurs.

“The fossil record tells us that feathers like the one we have studied were already present on a wide range of theropod dinosaurs, a group which included ground-running forms without flying ability, as well as bird-like dinosaurs capable of powered flight,” explains Dr Ricardo Pérez-de la Fuente, a research fellow at Oxford University Museum of Natural History and one of the authors of the study.

“So although we can’t be sure what kind of dinosaur the tick was feeding on, the mid-Cretaceous age of the Burmese amber confirms that the feather certainly did not belong to a modern bird, as these appeared much later in theropod evolution according to current fossil and molecular evidence.”

The researchers found further, indirect evidence of ticks parasitising dinosaurs in Deinocroton draculi, or “Dracula’s terrible tick,” belonging to a newly-described extinct group of ticks. This new species was also found sealed inside Burmese amber, with one specimen remarkably engorged with blood, increasing its volume approximately eight times over non-engorged forms. Despite this, it has not been possible to directly determine its host animal.

“Assessing the composition of the blood meal inside the bloated tick is not feasible because, unfortunately, the tick did not become fully immersed in resin and so its contents were altered by mineral deposition,” explains Dr Xavier Delclòs, an author of the study from the University of Barcelona and IRBio.

But indirect evidence of the likely host for these novel ticks was found in the form of hair-like structures, or setae, from the larvae of skin beetles (dermestids), found attached to two Deinocroton ticks preserved together. Today, skin beetles feed in nests, consuming feathers, skin and hair from the nest’s occupants. And as no mammal hairs have yet been found in Cretaceous amber, the presence of skin beetle setae on the two Deinocroton draculi specimens suggests that the ticks’ host was a feathered dinosaur.

“The simultaneous entrapment of two external parasites — the ticks — is extraordinary, and can be best explained if they had a nest-inhabiting ecology as some modern ticks do, living in the host’s nest or in their own nest nearby,” says Dr David Grimaldi of the American Museum of Natural History and an author of the work.

Together, these findings provide direct and indirect evidence that ticks have been parasitising and sucking blood from dinosaurs within the evolutionary lineage leading to modern birds for almost 100 million years. While the birds were the only lineage of theropod dinosaurs to survive the mass extinction at the end of the Cretaceous 66 million years ago, the ticks did not just cling on for survival, they continued to thrive.

  1. Enrique Peñalver, Antonio Arillo, Xavier Delclòs, David Peris, David A. Grimaldi, Scott R. Anderson, Paul C. Nascimbene, Ricardo Pérez-de la Fuente. Ticks parasitised feathered dinosaurs as revealed by Cretaceous amber assemblages. Nature Communications, 2017; 8 (1) DOI: 10.1038/s41467-017-01550-z
University of Oxford. “Dinosaur parasites trapped in 100-million-year-old amber tell blood-sucking story: Amber containing tick grasping a dinosaur feather is first direct fossil evidence of ticks parasitizing dinosaurs.” ScienceDaily. ScienceDaily, 13 December 2017. <www.sciencedaily.com/releases/2017/12/171213104735.htm>.
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WFS News: Rhaeticosaurus mertensi fossil gives clues to life in ancient oceans

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Source: Article By ,

Yasuhisa Nakajima Image caption Paleontologists Tanja Wintrich and Martin Sander examine the fossil

Yasuhisa Nakajima :Paleontologists Tanja Wintrich and Martin Sander examine the fossil

A new fossil is shedding light on the murky past of the sea reptiles that swam at the time of the dinosaurs.

With tiny heads on long necks and four pointed flippers, plesiosaurs have been likened to Scotland’s mythical Loch Ness monster.The German discovery proves that these sea creatures were alive more than 200 million years ago during the Triassic.

The fossilised bones give clues to how the animal survived a mass extinction that wiped out most living things.

”We now have the proof that this extremely successful group of marine reptiles already existed during Triassic times,” said paleontologist Martin Sander of the University of Bonn, who examined the fossil with colleague, Tanja Wintrich.

”This had been suspected for over 150 years, but it took a surprisingly long time for the hard evidence to emerge. ”

Long reign

The plesiosaur has been named Rhaeticosaurus mertensi.Growth marks in its bones suggest the sea creature was a juvenile, grew very quickly and was warm-blooded.

Fossil Of Rhaeticosaurus mertensi

         Fossil Of Rhaeticosaurus mertensi,The skeleton is 237cm long  :Georg Oleschinski

By being warm-blooded, plesiosaurs were able to roam the open seas in late Triassic times.

”Warm-bloodedness probably was the key to both their long reign and their survival of a major crisis in the history of life, the extinction events at the end of the Triassic,” said Prof Sander.

Plesiosaurs were not as hard hit by the extinction as shallow water and coastal animals. Their fossils have been found all over the world in Cretaceous and Jurassic rocks.

”What is also interesting is the location of the find in Germany, in Europe,” said Prof Sander.

”Three hundred years ago, the first plesiosaurs were found in England and the Continent, and now we have come full circle.”

The scientists found the skeleton buried in a clay pit owned by a German brick company near the village of Bonenburg.

The creature had a very stiff neck, which probably prevented it from twisting its head from front-to-back or side-to-side.

The research is published in the journal, Science Advances.

”’Triassic plesiosaur remains are few and far between, so the discovery of Rhaeticosaurus mertensi is really important in helping to understand what early plesiosaurs looked like,” said Dean Lomax of the University of Manchester, who was not connected with the study.

”’This will also provide new information about the early evolution of the group.”

Plesiosaurs ruled the oceans for more than a hundred million years before dying out at the same time as the dinosaurs.

Despite their dominance of the prehistoric oceans, there are still many unanswered questions about their biology, anatomy and evolution.

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Martin Sander Image caption The fossil was unearthed in a clay pit owned by a brick company

      Image caption The fossil was unearthed in a clay pit owned by a brick company : Martin Sander    

WFS News: Fossil hunters find bones of human-sized penguin on New Zealand beach

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The remnants of an ancient penguin that stood as tall as a human have been found encased in rock on a beach in New Zealand.

Fossil hunters chanced upon the prehistoric bones in sedimentary rock that formed 55m to 60m years ago on what is now Hampden beach in Otago in the country’s South Island.

This illustration shows the sizes of an ancient giant penguin Kumimanu biceae and a human being. Photograph: Gerald Mayr/AP

This illustration shows the sizes of an ancient giant penguin Kumimanu biceae and a human being. Photograph: Gerald Mayr/AP

Measurements of the partial skeleton show that the flightless bird weighed about 100kg and had a body length of 1.77 metres (5ft 10in), equal to the average height of an American man. Emperor penguins, the tallest penguin species alive today, reach only 1.2 metres when fully grown.

Penguins evolved from flying birds tens of millions of years ago, but lost the ability to get airborne and became accomplished swimmers instead. Once grounded, some penguin species became much larger, growing from about 80cm tall to twice the size.

The pieces of the latest skeleton, including wing, spine, breast and leg bones, were first discovered more than a decade ago, but the rock holding the fossilised bones was so hard that it has taken until now for researchers to prepare and study the remains.

The partly prepared skeleton of the Paleocene giant penguin Kumimanu biceae. The rectangles emphasise the humerus and a bone from the shoulder girdle (coracoid), which are shown separated from the original bone cluster. Photograph: Gerald Mayr/Senckenberg Research Institute

The partly prepared skeleton of the Paleocene giant penguin Kumimanu biceae. The rectangles emphasise the humerus and a bone from the shoulder girdle (coracoid), which are shown separated from the original bone cluster. Photograph: Gerald Mayr/Senckenberg Research Institute

Rather than the usual black-and-white colouring, the ancient penguin was probably brownish and had a longer beak than its modern-day cousins. “It would most likely have been slimmer too and not so cute looking,” said Gerald Mayr at the Senckenberg Research Institute and Natural History Museum in Frankfurt. “It’s one of the tallest penguins that has ever been found.”

Researchers named the new species Kumimanu biceae, after the Maori words “kumi”, meaning a large mythological monster, and “manu” for bird. The second part of the name honours Beatrice Tennyson, known as “Bice”, the mother of Alan Tennyson, a senior researcher on the team.

The fossilised remains of giant penguins have been found from 20m to 50m years ago, but older examples are extremely rare. The latest specimen, reported in Nature Communications, suggests that some penguins became giants soon after penguins first evolved and switched from flight to diving. At the time the newly discovered species was alive it would have shared the warm subtropical environment with other sea birds, turtles and sharks.

Giant penguins went extinct about 20m years ago ,when marine mammals arrived in the form of toothed whales, seals and other creatures. What spelled the end is unclear, but the big birds may have struggled to compete with marine mammals for food, or may have become the meal of choice for the new predators.

Another species of giant penguin, discovered in Antarctica in 2014, may have been even taller than Kumimanu biceae. Bones from the 37m-year-old “colossus penguin”, or Palaeeudyptes klekowskii, suggest the animal stretched two metres from beak to foot and weighed 115kg.

Source: The guardian

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WFS News: Los Angeles construction unearths ‘rare’ fossil trove

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Paleontologist Ashley Leger shows the skull of a young Columbian mammoth found at the construction site of the Metro Purple Line extension in Los Angeles.  (AP)

Paleontologist Ashley Leger shows the skull of a young Columbian mammoth found at the construction site of the Metro Purple Line extension in Los Angeles. (AP)

The fossilized remains of creatures that roamed southern California 10,000 years ago were discovered by a crew digging for a subway extension under the busy streets of Los Angeles.

Ashley Leger works for a company contracted by Los Angeles transportation officials to keep paleontologists on hand as the city extends the purple line to the west side.

When Leger gets a notification on her phone, she dons a neon vest, hard hat and goggles before climbing deep into a massive construction site beneath a boulevard east of downtown.

Since work on the extension began in 2014, fossilized remains—including a partial rabbit jaw, mastodon tooth, camel foreleg, bison vertebrae and a horse’s ankle bone—have turned up from creatures that roamed the grasslands and forests that covered the region about 10,000 years ago in the last Ice Age.

A worker stands near a backhoe at the construction site of the Metro Purple Line extension in Los Angeles.  (AP)

A worker stands near a backhoe at the construction site of the Metro Purple Line extension in Los Angeles. (AP)

‘JAWS’ SPOTTED? MASSIVE GREAT WHITE SEEN OFF AUSTRALIAN COAST 

But the discovery that makes Leger shake her head in disbelief came about a year ago. When she arrived at the site, Leger recognized what appeared to be a partial elephant skull.

It turned out to be a much bigger discovery. After 15 hours of excavation, the team uncovered an intact skull of a juvenile mammoth.

“It’s an absolute dream come true for me,” Leger, who spent the previous decade at a South Dakota mammoth site with no discoveries even close to the size of the one in Los Angeles, said. “It’s the one fossil you always want to find in your career.”

California’s strict environmental laws require scientists to be on hand at certain construction sites.

BRITAIN’S BEEN WRONG ABOUT ITS HIGHEST MOUNTAIN FOR YEARS

Assistant curator Dr. Emily Lindsey called it a “pretty remarkable find,” noting that while thousands of dire wolf and saber-toothed cat remains have been uncovered in L.A., there have been only about 30 mammoths.

A few hundred pounds and the size of an easy chair, the skull is especially rare because both tusks were attached. It’s being studied and is available for public viewing inside the museum’s glass-walled Fossil Lab.

With a nod to Hollywood, the 8- to 12-year-old Colombian mammoth was named Hayden, for the actress Hayden Panettiere, featured in the TV series “Nashville” and “Heroes.”

The Associated Press contributed to this report. 

Source: foxnews.com

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WFS News:Wakaleo schouteni,New species of extinct marsupial lion

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A team of Australian scientists has discovered a new species of marsupial lion which has been extinct for at least 19 million years. The findings, published in the Journal of Systematic Palaeontology, are based on fossilised remains of the animal’s skull, teeth, and humerus (upper arm bone) found by University of New South Wales (UNSW) scientists in the Riversleigh World Heritage Area of remote north-western Queensland.

Named in honour of palaeoartist Peter Schouten, Wakaleo schouteni was a predator that stalked Australia’s abundant rainforests some 18 to 26 million years ago in the late Oligocene to early Miocene era. This meat-eating marsupial is estimated to have been about the size of a dog and weighed around 23 kilograms.

Reconstruction of Wakaleo schouteni challenging the thylacinid Nimbacinus dicksoni over a kangaroo carcass in the late Oligocene forest at Riversleigh. Credit: Illustration by Peter Schouten in the Journal of Systematic Palaeontology

Reconstruction of Wakaleo schouteni challenging the thylacinid Nimbacinus dicksoni over a kangaroo carcass in the late Oligocene forest at Riversleigh.
Credit: Illustration by Peter Schouten in the Journal of Systematic Palaeontology

The new species is about a fifth of the weight of the largest and last surviving marsupial lion, Thylacoleo carnifex, that weighed in at around 130 kilograms and which has been extinct for 30,000 years. Members of this family, the Thylacoleonidae, had highly distinct large, blade-like, flesh-cutting premolars that they used to tear up prey.

The discovery comes just a year after the fossilised remains of a kitten-sized marsupial lion were found in the same famous fossil site in Queensland. The UNSW scientists named that miniature predator Microleo attenboroughi after broadcasting legend Sir David Attenborough.

With this new find, the researchers believe that two different species of marsupial lion were present in the late Oligocene at least 25 million years ago. The other, originally named Priscileo pitikantensis, but renamed Wakaleo pitikantensis, was slightly smaller and was identified from teeth and limb bones discovered near Lake Pitikanta in South Australia in 1961.

This latest discovery reveals that the new species (W. schouteni) exhibits many skull and dental features of the genus Wakaleo but it also shared a number of similarities with P. pitikantensis — particularly the presence of three upper premolars and four molars, previously the diagnostic feature of Priscileo. Further similarities of the teeth and humerus which are shared with W. schouteni indicate that P. pitikantensis is a species of Wakaleo.

According to the authors, these dental similarities distinguish W. schouteni and W. pitikantensis from later species of this genus, all of which show premolar and molar reduction, and suggest that they are the most primitive members of the genus.

Lead author Dr Anna Gillespie, a palaeontologist from the University of New South Wales (UNSW) in Sydney, Australia says that the latest finding raises new questions about the evolutionary relationships of marsupial lions: “The identification of these new species have brought to light a level of marsupial lion diversity that was quite unexpected and suggest even deeper origins for the family.”

  1. Anna K. Gillespie, Michael Archer, Suzanne J. Hand. A new Oligo–Miocene marsupial lion from Australia and revision of the family Thylacoleonidae. Journal of Systematic Palaeontology, 2017; 1 DOI: 10.1080/14772019.2017.1391885
Taylor & Francis Group. “New species of extinct marsupial lion discovered in Australia.” ScienceDaily. ScienceDaily, 6 December 2017. <www.sciencedaily.com/releases/2017/12/171206193754.htm>.
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WFS News: Recently discovered fossil shows transition of a reptile from life on land to life in the sea

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Using modern research tools on a 155-million-year-old reptile fossil, scientists at Johns Hopkins and the American Museum of Natural History report they have filled in some important clues to the evolution of animals that once roamed land and transitioned to life in the water.

A report on the new discoveries about the reptile, Vadasaurus herzogi, appears online in the Nov. 8 issue of Royal Society Open Science, and suggests that some of the foot-long animal’s features, including its elongated, whip-like tail, and triangular-shaped head, are well suited to aquatic life, while its relatively large limbs link it to land-loving species.

Holotype of Vadasaurus herzogi (AMNH FARB 32768) collected from the Late Jurassic marine limestones of Solnhofen, Bavaria. The skull, forelimbs, and first 18 presacral vertebrae and ribs are exposed in the dorsal or dorsolateral view. Posteriorly, the skeleton is rotated approximately 180°, making it visible largely in the ventral view. Left hindlimb is exposed in the dorsal view. Anatomical abbreviations: As, astragalus; Ca, calcaneum; Cdv, caudal vertebra; Co, coracoid; Cr, cervical rib; Cv, cervical vertebra; D, dentary; Dv, dorsal vertebra; F, femur; Fb, fibula; Fr, frontal; Ga, gastralia; H, humerus; I, intermedium; Is, ischium; l, left; Mc, metacarpal; Mt, metatarsal; Mx, maxilla; Ph, phalanx; Pu, pubis; R, radius; r, right; S, scapula; Sc, sternal cartilage; Ss, suprascapular cartilage; Sv, sacral vertebra; T, tibia; U, ulna.

Holotype of Vadasaurus herzogi (AMNH FARB 32768) collected from the Late Jurassic marine limestones of Solnhofen, Bavaria. The skull, forelimbs, and first 18 presacral vertebrae and ribs are exposed in the dorsal or dorsolateral view. Posteriorly, the skeleton is rotated approximately 180°, making it visible largely in the ventral view. Left hindlimb is exposed in the dorsal view. Anatomical abbreviations: As, astragalus; Ca, calcaneum; Cdv, caudal vertebra; Co, coracoid; Cr, cervical rib; Cv, cervical vertebra; D, dentary; Dv, dorsal vertebra; F, femur; Fb, fibula; Fr, frontal; Ga, gastralia; H, humerus; I, intermedium; Is, ischium; l, left; Mc, metacarpal; Mt, metatarsal; Mx, maxilla; Ph, phalanx; Pu, pubis; R, radius; r, right; S, scapula; Sc, sternal cartilage; Ss, suprascapular cartilage; Sv, sacral vertebra; T, tibia; U, ulna.

Vadasaurus, which is the Latin term for “wading lizard,” was discovered in limestone quarries near Solnhofen, Germany, part of a once-shallow sea long explored for its rich trove of fossil finds.

The well-preserved fossil is housed in the American Museum of Natural History in New York, where the job of unlocking its evolutionary secrets fell to museum research associate Gabriel Bever, Ph.D., who is also assistant professor of functional anatomy and evolution at the Johns Hopkins University School of Medicine, and Mark Norell, Ph.D., the museum’s paleontology division chair.

“Anatomic and behavioral characteristics of modern groups of living things accumulated over long spans of time,” says Bever. “Fossils can teach us a lot about that evolutionary history, including the order in which those features evolved and their adaptive role in a changing environment.”

The skull of Vadasaurus herzogi (AMNH FARB 32768). Photographs in the dorsolateral (a) and lateral (b) views; labelled line drawing in the dorsolateral view (c); reconstructions of lateral and dorsal views (d). Anatomical abbreviations: An, angular; Ar, articular; cp, cultriform process; Cv, cervical vertebra; D, dentary; dd, dentary dentition; Ecp, ectopterygoid; Ept, epipterygoid; exn, external naris; Fr, frontal; Hy, hyobranchial element; if, incisiform fang; Ju, jugal; mf, mandibular foramen; Mx, maxilla; Na, nasal; Pa, parietal; Pal, palatine; paf, parietal foramen; Pf, prefrontal; Pm, premaxilla; Po, postorbital; Pof, postfrontal; Pr, prootic; Pra, prearticular; Pt, pterygoid; Q, quadrate; Qj, quadratojugal; Sa, surangular; sof, suborbital fenestra; Sq, squamosal; Vo, vomer.

The skull of Vadasaurus herzogi (AMNH FARB 32768). Photographs in the dorsolateral (a) and lateral (b) views; labelled line drawing in the dorsolateral view (c); reconstructions of lateral and dorsal views (d). Anatomical abbreviations: An, angular; Ar, articular; cp, cultriform process; Cv, cervical vertebra; D, dentary; dd, dentary dentition; Ecp, ectopterygoid; Ept, epipterygoid; exn, external naris; Fr, frontal; Hy, hyobranchial element; if, incisiform fang; Ju, jugal; mf, mandibular foramen; Mx, maxilla; Na, nasal; Pa, parietal; Pal, palatine; paf, parietal foramen; Pf, prefrontal; Pm, premaxilla; Po, postorbital; Pof, postfrontal; Pr, prootic; Pra, prearticular; Pt, pterygoid; Q, quadrate; Qj, quadratojugal; Sa, surangular; sof, suborbital fenestra; Sq, squamosal; Vo, vomer.

“Anytime we can get a fossil like this that is so well preserved, and so significant in understanding a major environmental transition, it is very important,” says Norell. “It’s so important,” he adds, “that we can consider Vadasaurus to be the Archaeopteryx of rynchocephalians.”

According to Bever, their work adds to the list of sea creatures whose ancestors were land-dwelling vertebrates. They include modern-day whales, seals, and sea snakes, and ancient (and now-extinct) species of ichthyosaurs, mosasaur, and plesiosaurs.

Bever says their study offers evidence that Vadasaurus, likely an adult when it died, can be linked by its anatomy to a small group of marine species called pleurosaurs, which have long been thought to have terrestrial roots. Pleurosaurs lived during the Jurassic period, 185 to 150 million years ago. The eel-like creatures had reduced limbs that were probably used for steering rather than propulsion in the water. Until now, fossils of only three ancient species of pleurosaurs have been discovered.

Using two types of statistical algorithms and reconstructions of evolutionary “trees,” Bever and Norell say that Vadasaurus and the pleurosaurs are part of a larger lineage of reptiles called Rhynchocephalia. Like the sea-loving pleurosaurs, Vadasaurus’ skull was a triangular shape, an adaptation found among many streamlined, water-dwelling animals, such as most fish, eels and whales. An elongated snout, common among sea animals, featured teeth farther away from the body for ensnaring fish.

By examining the shape and structure of the Vadasaurus’ skull, Bever and Norell also concluded that Vadasaurus’ bite was likely a quick, side-to-side motion, compared with the slower, stronger bite typical of many land-dwelling animals.

Some 155 million years ago, Vadasaurus’ tail had begun to lengthen like most modern sea animals, says Bever, but not to the size of the 5-foot pleurosaur. Vadasaurus, they found, had 24 pre-sacral vertebrae, which span from the head to the beginning of the tail, whereas pleurosaurus had more than 50 such back bones.

Despite its aquatic features, Vadasaurus retained some features more often found among land vertebrates. For example, Vadasaurus still had the large limbs, relative to the size of its body, expected of a land-dwelling reptile. Bever speculates that Vadasaurus did not use its limbs for propulsion in the water, but to steer. He says Vadasaurus may have swum like a modern sea snake, moving its spinal column with an undulating kind of motion.

“Our data indicate that Vadasaurus is an early cousin of the pleurosaur,” says Bever. “And these two reptiles are closely related to modern tuatara.” The modern tuatara is a lizard-like, land-dwelling reptile that lives on New Zealand’s coastal islands and is the single remaining species of rhynchocephalian still left on Earth.

Bever notes that a complete evolutionary history of Vadasaurus will require more data and fossil finds.

“We don’t know exactly how much time Vadasaurus was spending on land versus in the water. It may be that the animal developed its aquatic adaptations for some other reason, and that these changes just happened to be advantageous for life in the water,” says Bever.

  1. Gabriel S. Bever, Mark A. Norell. A new rhynchocephalian (Reptilia: Lepidosauria) from the Late Jurassic of Solnhofen (Germany) and the origin of the marine Pleurosauridae. Royal Society Open Science, 2017; 4 (11): 170570 DOI: 10.1098/rsos.170570
Johns Hopkins Medicine. “Recently discovered fossil shows transition of a reptile from life on land to life in the sea: Modern New Zealand reptile may be a close relative.” ScienceDaily. ScienceDaily, 6 December 2017. <www.sciencedaily.com/releases/2017/12/171206090713.htm>.
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WFS News: Synchrotron scanning reveals amphibious ecomorphology in a new clade of bird-like dinosaurs

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An exceptionally well-preserved dinosaur skeleton from Mongolia unites an unexpected combination of features that defines a new group of semi-aquatic predators related to Velociraptor. Detailed 3D synchrotron analysis allowed an international team of researchers to present the bizarre 75 million-year-old predator, named Halszkaraptor escuilliei, in Nature. The study not only describes a new genus and species of bird-like dinosaur that lived during the Campanian stage of the Cretaceous in Mongolia but also sheds light on an unexpected amphibious lifestyle for raptorial dinosaurs.

a, Virtual section or the original dataset. b, Detail of a. c, Virtual section from the dataset corrected for metallic inclusions. d, Detail of c. Histograms along the blue and red lines demonstrate how metallic inclusions prevent adjusting the contrast to focus on the bone–matrix contact. e, Virtual section along the longitudinal axis of the cranium on dataset corrected for metallic inclusions. f, Detail of e. g, Same virtual section as in e, on data processed with the texture enhancement algorithm. h, Detail of g. In the processed data (g, h), homogenous parts (for example, bone or plaster) appear dark and the sediment reveals features that were barely visible prior to processing (e, f).

a, Virtual section or the original dataset. b, Detail of a. c, Virtual section from the dataset corrected for metallic inclusions. d, Detail of c. Histograms along the blue and red lines demonstrate how metallic inclusions prevent adjusting the contrast to focus on the bone–matrix contact. e, Virtual section along the longitudinal axis of the cranium on dataset corrected for metallic inclusions. f, Detail of e. g, Same virtual section as in e, on data processed with the texture enhancement algorithm. h, Detail of g. In the processed data (g, h), homogenous parts (for example, bone or plaster) appear dark and the sediment reveals features that were barely visible prior to processing (e, f).

Theropods encompass all carnivorous dinosaurs, including the largest land-living predators in the history of life on Earth, such as Tyrannosaurus, and iconic agile hunters like Velociraptor. During 160 million years of the Mesozoic Era, theropods became the dominant predators on all continents, yet never conquered aquatic environments. Although some theropods reportedly incorporated fish in their diet, proposed indications for aquatic locomotion associated with exclusively aquatic lifestyles remain controversial.

a, Detail of anterior end of neck and posterior half of skull that shows continuity of the craniocervical transition. b, Detail of neck and skull that shows continuity between bones and matrix. c, Detail of proximal caudal series that shows the glued crack that crosses both matrix and bone (arrow), which confirms continuity between the sacrum and tail. d, Selected series of slices that show the continuity of bones and matrix along main slab. e, Overview of MPC-D102/109 indicating the curved virtual slice along a polyline (materialized above a 3D rendering) with slices at 5 mm on each side of this line every 1 mm. The line follows the axial column in order to show the continuity of the vertebral series. Scale bar, 70 mm. The renderings are generated using scan data that have been corrected for the absorbing metallic oxide infilling.

a, Detail of anterior end of neck and posterior half of skull that shows continuity of the craniocervical transition. b, Detail of neck and skull that shows continuity between bones and matrix. c, Detail of proximal caudal series that shows the glued crack that crosses both matrix and bone (arrow), which confirms continuity between the sacrum and tail. d, Selected series of slices that show the continuity of bones and matrix along main slab. e, Overview of MPC-D102/109 indicating the curved virtual slice along a polyline (materialized above a 3D rendering) with slices at 5 mm on each side of this line every 1 mm. The line follows the axial column in order to show the continuity of the vertebral series. Scale bar, 70 mm. The renderings are generated using scan data that have been corrected for the absorbing metallic oxide infilling.

A swan-necked and flipper-forelimbed new dinosaur species that combines an unexpected mix of features now demonstrates that some bird-like dinosaurs did adopt a semi-aquatic lifestyle. The fossil, nicknamed “Halszka” for Halszkaraptor escuilliei, was found at Ukhaa Tolgod. This locality in southern Mongolia has been known by palaeontologists for decades and is often targeted by poachers. “Illicit fossil trade presents a great challenge to modern palaeontology and accounts for a dramatic loss of Mongolian scientific heritage,” says Pascal Godefroit of the Royal Belgian Institute of Natural Sciences in Brussels. “Illegally exported from Mongolia, Halszka resided in private collections around the world before it was acquired in 2015 and offered to palaeontologists for study and to prepare its return to Mongolia.”

Reconstruction of Halszkaraptor escuilliei. This small dinosaur was a close relative of Velociraptor, but in both body shape and inferred lifestyle it much closely recalls some waterbirds like modern swans. Credit: Lukas Panzarin; and Andrea Cau for scientific supervision

Reconstruction of Halszkaraptor escuilliei. This small dinosaur was a close relative of Velociraptor, but in both body shape and inferred lifestyle it much closely recalls some waterbirds like modern swans.
Credit: Lukas Panzarin; and Andrea Cau for scientific supervision

Although several important groups of predatory dinosaurs have been discovered in Mongolia, Halszka does not belong to any of them, having a number of strange features that are mostly absent among dinosaurs, but are shared by reptilian and avian groups with aquatic or semiaquatic ecologies. “The first time I examined the specimen, I even questioned whether it was a genuine fossil” says Andrea Cau of the Geological Museum Capellini in Bologna. Although Halszka is unique in many ways, certain parts of the skeleton, including the sickle-shaped “killer claws” on its feet, are shared with well-known dinosaurs such as Velociraptor. “This unexpected mix of traits makes it difficult to place Halszka within traditional classifications,” Cau remarks.

a, Dorsal view. b, Palatal view. p11, 11th premaxillary tooth; m16, 16th maxillary alveolus. c, Semi-transparent left lateral view that shows dentition. d, Left lateral view. af, antorbital fossa; en, external naris; mr, maxillary recess; pms, premaxillo-maxillary suture. e, Semi-transparent right lateral view that shows dentition. f, Right lateral view. en, external naris; nf, neurovascular foramina. Scale bars, 3 mm.

a, Dorsal view. b, Palatal view. p11, 11th premaxillary tooth; m16, 16th maxillary alveolus. c, Semi-transparent left lateral view that shows dentition. d, Left lateral view. af, antorbital fossa; en, external naris; mr, maxillary recess; pms, premaxillo-maxillary suture. e, Semi-transparent right lateral view that shows dentition. f, Right lateral view. en, external naris; nf, neurovascular foramina. Scale bars, 3 mm.

In order to ascertain the integrity of the fossil, the specimen was visualised and reconstructed in three dimensions using synchrotron multi-resolution X-ray microtomography. “This technique is currently the most powerful and sensitive method to image internal details without damaging invaluable fossils. The ESRF has become the worldwide leader for high quality X-ray imaging of such precious specimens,” notes Paul Tafforeau of the ESRF. “We had to mobilise an ESRF team of palaeontologists to study the complete anatomy of Halzka. So far, it’s the specimen for which the greatest number of experiments were made on a single fossil,” adds Tafforeau.

“Our first goal was to demonstrate that this bizarre and unexpected fossil is indeed a genuine animal: multi-resolution scanning confirmed that the skeleton is not a composite assembled from parts of different dinosaurs,” explains Dennis Voeten of the ESRF. “We implemented new methods for the acquisition and optimisation of tomographic scan data, which not only confirmed the integrity of the specimen, but also revealed additional palaeontological information,” Vincent Fernandez of the ESRF clarifies.

a, Premaxillary teeth in labial view. b, Premaxillary teeth in lingual view. c, Maxillary teeth in labial view. d, Maxillary teeth in lingual view. e, Maxillary teeth in basal view. f, Dentary teeth in lingual view. rt, replacement tooth. Scale bars, 1 mm.

a, Premaxillary teeth in labial view. b, Premaxillary teeth in lingual view. c, Maxillary teeth in labial view. d, Maxillary teeth in lingual view. e, Maxillary teeth in basal view. f, Dentary teeth in lingual view. rt, replacement tooth. Scale bars, 1 mm.

The synchrotron was even able to reveal, in astonishing detail, those parts of the skeleton that have remained deep within the rock ever since the dinosaur got buried. “Our analysis demonstrated that numerous teeth, which are not visible externally, are still preserved inside the mouth,” says Vincent Beyrand of the ESRF. “We also identified a neurovascular mesh inside its snout that resembles those of modern crocodiles to a remarkable degree. These aspects suggest that Halszka was an aquatic predator.”

The ESRF data revealed that the fossil represents a new genus and species of amphibious dinosaur that walked on two legs on land, with postural adaptations similar to short-tailed birds (like ducks), but used its flipper-like forelimbs to manoeuvre in water (like penguins and other aquatic birds), relying on its long neck for foraging and ambush hunting.

This new species was named Halszkaraptor escuilliei. Its generic name honours the late palaeontologist Halszka Osmólska. “This important genus is named in recognition of Halszka’s contribution to the study of Mongolian dinosaurs from the Gobi,” comments Rinchen Barsbold of the Mongolian Academy of Sciences. “The specific name refers to François Escuillié and thereby acknowledges his role in the first recognition and in the return of this specimen to Mongolia,” adds Khishigjav Tsogtbaatar of the Institute of Paleontology and Geology in Ulaanbaatar.

Halszkaraptor is not the only strange dinosaur recovered from the Gobi. Several previously described enigmatic Mongolian theropods were closely related to the new species, the study found. United in a new group, named Halszkaraptorinae, “is an unexpected subfamily of dromaeosaurs — the group colloquially known as raptors. This bizarre subfamily appears to have evolved a lifestyle different from all other predatory dinosaurs,” says Philip Currie of the University of Alberta.

“When we look beyond fossil dinosaurs, we find most of Halszkaraptor‘s unusual features among aquatic reptiles and swimming birds,” concludes lead author Andrea Cau. “The peculiar morphology of Halszkaraptor fits best with that of an amphibious predator that was adapted to a combined terrestrial and aquatic ecology: a peculiar lifestyle that was previously unreported in these dinosaurs. Thanks to synchrotron tomography, we now demonstrate that raptorial dinosaurs not only ran and flew, but also swam!”

  1. Andrea Cau, Vincent Beyrand, Dennis F. A. E. Voeten, Vincent Fernandez, Paul Tafforeau, Koen Stein, Rinchen Barsbold, Khishigjav Tsogtbaatar, Philip J. Currie, Pascal Godefroit. Synchrotron scanning reveals amphibious ecomorphology in a new clade of bird-like dinosaurs. Nature, 2017; DOI: 10.1038/nature24679
  2. European Synchrotron Radiation Facility. “Synchrotron sheds light on the amphibious lifestyle of a new raptorial dinosaur.” ScienceDaily. ScienceDaily, 6 December 2017. <www.sciencedaily.com/releases/2017/12/171206132218.htm>.
  3. @WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Early avian evolution: The Archaeopteryx that wasn‘t

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Paleontologists at Ludwig-Maximilians-Universitaet (LMU) in Munich correct a case of misinterpretation: The first fossil “Archaeopteryx” to be discovered is actually a predatory dinosaur belonging to the anchiornithid family, which was previously known only from finds made in China.

Overview of the “Haarlem specimen”, holotype of Ostromia crassipes (Meyer, 1857). Counterslab, Teylers Museum TM 6929 (left) and main slab, TM 6928 (right). Rectangles indicate areas detailed in Fig. 3 (yellow) and Fig. 6 (white)

Overview of the “Haarlem specimen”, holotype of Ostromia crassipes (Meyer, 1857). Counterslab, Teylers Museum TM 6929 (left) and main slab, TM 6928 (right). Rectangles indicate areas detailed in Fig. 3 (yellow) and Fig. 6 (white)

Even 150 million years after its first appearance on our planet, Archaeopteryx is still good for surprises. The so-called Urvogel has attained an iconic status well beyond the world of paleontology, and it is one of the most famous fossils ever recovered. In all, a dozen fossil specimens have been assigned to the genus. Archaeopteryx remains the oldest known bird fossil, not only documenting the evolutionary transition from reptiles to birds, but also confirming that modern birds are the direct descendants of carnivorous dinosaurs. LMU paleontologist Oliver Rauhut and Christian Foth from the Staatliches Museum für Naturkunde in Stuttgart have re-examined the so-called Haarlem specimen of Archaeopteryx, which is kept in Teylers Museum in that Dutch city and has gone down in history as the first member of this genus to be discovered.

Anatomical details of the manus of Ostromia crassipes and Anchiornis huxleyi. a Detail of the preserved elements of the right manus on the main slab, showing longitudinal furrows (or their impressions) in metacarpal III and the manual phalanges (arrows). b Detail of the preserved elements of the right manus on the counterslab of the holotype of Ostromia crassipes (TM 6929), showing longitudinal furrows (or their impressions) in the manual phalanges (arrows). c, d Impression (c) and high-resolution cast (d) of the left manus of the holotype of Anchiornis huxleyi (Institute of Vertebrate Paleontology and Paleoanthropology IVPP V 14378), showing longitudinal furrows in the manual phalanges (arrows). All scale bars are 10 mm

Anatomical details of the manus of Ostromia crassipes and Anchiornis huxleyi. a Detail of the preserved elements of the right manus on the main slab, showing longitudinal furrows (or their impressions) in metacarpal III and the manual phalanges (arrows). b Detail of the preserved elements of the right manus on the counterslab of the holotype of Ostromia crassipes (TM 6929), showing longitudinal furrows (or their impressions) in the manual phalanges (arrows). c, d Impression (c) and high-resolution cast (d) of the left manus of the holotype of Anchiornis huxleyi (Institute of Vertebrate Paleontology and Paleoanthropology IVPP V 14378), showing longitudinal furrows in the manual phalanges (arrows). All scale bars are 10 mm

In the journal BMC Evolutionary Biology, Foth and Rauhut now report that this fossil differs in several important respects from the other known representatives of the genus Archaeopteryx. In fact, their taxonomic analysis displaces it from its alleged perch on the phylogenetic tree: “The Haarlem specimen is not a member of the Archaeopteryx clade,” says Rauhut, a paleontologist in the Department of Earth and Environmental Sciences at LMU who is also affiliated with the Bavarian State Collections for Paleontology and Geology in Munich.

Details of manual phalanx I-1 of Ostromia crassipes, showing the regular development and non-collapsed margins of the longitudinal groove. a, stereophotograph. b, magnification of the shaft of the phalanx

Details of manual phalanx I-1 of Ostromia crassipes, showing the regular development and non-collapsed margins of the longitudinal groove. a, stereophotograph. b, magnification of the shaft of the phalanx

Instead, the two scientists assign the fossil to a group of bird-like maniraptoran dinosaurs known as anchiornithids, which were first identified only a few years ago based on material found in China. These rather small dinosaurs possessed feathers on all four limbs, and they predate the appearance of Archaeopteryx. “The Haarlem fossil is the first member of this group found outside China. And together with Archaeopteryx, it is only the second species of bird-like dinosaur from the Jurassic discovered outside eastern Asia. This makes it even more of a rarity than the true specimens of Archaeopteryx,” Rauhut says.

Manual phalanges of several other theropods preserved in highly compacted sediments, showing differences (a-d, f) and similarities (e) in preservation to the manual furrows in the Haarlem specimen. a Right manus of the Thermopolis specimen of Archaeopteryx, showing non-collapsed phalanges without furrows, as they are found in many specimens of this taxon (e.g. London, Berlin, Eichstätt, Munich, 11th specimen). b Right manus of the Solnhofen specimen of Archaeopteryx, showing partially collapsed and crushed phalanges with clearly broken margins. c Left manus of Sciurumimus albersdoerferi (BMMS BK 11) under UV light, showing partially compressed phalanges in this juvenile theropod. d Phalanx II-2 of Compsognathus longipes (SNSB-BSPG AS I 563), showing non-collapsed, but partially broken shaft. e Impression of phalanx I-1 of the holotype of Anchiornis huxleyi (IVPP V 14378), showing the impression of a regular longitudinal furrow, very similar to the impressions seen in the Haarlem specimen. f Phalanx I-1 of Caudipteryx (IVPP V 12430), showing collapse structure distally with clearly broken margins. Scale bars are in mm increments

Manual phalanges of several other theropods preserved in highly compacted sediments, showing differences (a-d, f) and similarities (e) in preservation to the manual furrows in the Haarlem specimen. a Right manus of the Thermopolis specimen of Archaeopteryx, showing non-collapsed phalanges without furrows, as they are found in many specimens of this taxon (e.g. London, Berlin, Eichstätt, Munich, 11th specimen). b Right manus of the Solnhofen specimen of Archaeopteryx, showing partially collapsed and crushed phalanges with clearly broken margins. c Left manus of Sciurumimus albersdoerferi (BMMS BK 11) under UV light, showing partially compressed phalanges in this juvenile theropod. d Phalanx II-2 of Compsognathus longipes (SNSB-BSPG AS I 563), showing non-collapsed, but partially broken shaft. e Impression of phalanx I-1 of the holotype of Anchiornis huxleyi (IVPP V 14378), showing the impression of a regular longitudinal furrow, very similar to the impressions seen in the Haarlem specimen. f Phalanx I-1 of Caudipteryx (IVPP V 12430), showing collapse structure distally with clearly broken margins. Scale bars are in mm increments

Made in China

The Haarlem specimen was found about 10 km to the northeast of the closest Archaeopteryx locality known (Schamhaupten) a full four years before the discovery of the skeleton that would introduce the Urvogel to the scientific world in 1861. Schamhaupten was once part of the so-called Solnhofen archipelago in the Altmühl Valley in southern Bavaria, the area from which all known specimens of the genus Archaeopteryx originated. Its taxonomic reassignment therefore provides new insights into the evolution of the bird-like dinosaurs in the Middle to Late Jurassic. “Our biogeographical analysis demonstrates that the group of dinosaurs that gave rise to birds originated in East Asia — all of the oldest finds have been made in China. As they expanded westward, they also reached the Solnhofen archipelago,” says Christian Foth. Thus, the fossil hitherto incorrectly assigned to the genus Archaeopteryx must have been one of the first members of the group to arrive in Europe.

Around 150 million years ago, the area known today as the Altmühl Valley was dotted with the coral and sponge reefs and lagoons of the Solnhofen archipelago, and the open sea lay to the West and South. The Haarlem fossil was originally recovered from what was then the eastern end of the archipelago, quite close to the mainland. Unlike Archaeopteryx, anchiornithids were unable to fly, and might not have been able to reach areas further offshore. On the other hand, all true fossils of Archaeopteryx found so far were recovered from the lithographic limestone strata further to the west, closer to the open sea. Based on the new findings, Rauhut argues that other known Archaeopteryx fossils may need reassessment: “Not every bird-like fossil that turns up in the fine-grained limestones around Solnhofen need necessarily be a specimen of Archaeopteryx,” he points out.

The authors of the new study have proposed that the Haarlem specimen be assigned to a new genus, for which they suggest the name Ostromia — in honor of the American paleontologist John Ostrom, who first identified the fossil as a theropod dinosaur.

  1. Christian Foth, Oliver W. M. Rauhut. Re-evaluation of the Haarlem Archaeopteryx and the radiation of maniraptoran theropod dinosaurs. BMC Evolutionary Biology, 2017; 17 (1) DOI: 10.1186/s12862-017-1076-y
Ludwig-Maximilians-Universitaet Muenchen (LMU). “Early avian evolution: The Archaeopteryx that wasn‘t.” ScienceDaily. ScienceDaily, 4 December 2017. <www.sciencedaily.com/releases/2017/12/171204150650.htm>.
@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Gravity Signals to Measure Strong Earthquakes

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After an earthquake, there is a disturbance in the field of gravity almost instantaneously. This could be recorded before the seismic waves that seismologists usually analyze. In a study published in Science on December 1, 2017, a team formed of researchers from CNRS, IPGP, the Université Paris Diderot and Caltech has managed to observe these weak signals related to gravity and to understand where they come from. Because they are sensitive to the magnitude of earthquakes, these signals may play an important role in the early identification of the occurrence of a major earthquake.

Seismograph (stock image). Credit: © hakandogu / Fotolia

Seismograph (stock image).Credit: © hakandogu / Fotolia

This work came out of the interaction between seismologists who wanted to better understand earthquakes and physicists who were developing fine gravity measurements with a view to detecting gravitational waves. Earthquakes change the equilibrium of forces on Earth brutally and emit seismic waves whose consequences may be devastating. But these same waves also disturb Earth’s field of gravity, which emits a different signal. This is particularly interesting with a view to fast quantification of tremors because it moves at the speed of light, unlike tremor waves, which propagate at speeds between 3 and 10 km/s. So seismometers at a station located 1000 km from the epicenter may potentially detect this signal more than two minutes before the seismic waves arrive.

The work presented here, which follows on a 2016 study which demonstrated this signal for the first time, greatly increases its understanding. First, the scientists did indeed observe these signals on the data from about ten seismometers located between 500 and 3000 km from the epicenter of the 2011 Japanese earthquake (magnitude 9.1). From their observations, the researchers then demonstrated that these signals were due to two effects. The first is the gravity change that occurs at the location of the seismometer, which changes the equilibrium position of the instrument’s mass. The second effect, which is indirect, is due to the gravity change everywhere on Earth, which disturbs the equilibrium of the forces and produces new seismic waves that will reach the seismometer.

Taking account of these two effects, the researchers have shown that this gravity-related signal is very sensitive to the earthquake’s magnitude, which makes it a good candidate for rapidly quantifying the magnitude of strong earthquakes. The future challenge is to manage to exploit this signal for magnitudes below about 8 to 8.5, because below this threshold, the signal is too weak relative to the seismic noise emitted naturally by Earth, and dissociating it from this noise is complicated. So several technologies, including some inspired from instruments developed to detect gravitational waves, are being envisaged to take a new step forward in detection of these precious signals.

  1. Martin Vallée, Jean Paul Ampuero, Kévin Juhel, Pascal Bernard, Jean-Paul Montagner, Matteo Barsuglia. Observations and modeling of the elastogravity signals preceding direct seismic waves. Science, 2017; DOI: 10.1126/science.aao0746
CNRS. “New early gravity signals to quantify the magnitude of strong earthquakes.” ScienceDaily. ScienceDaily, 30 November 2017. <www.sciencedaily.com/releases/2017/11/171130141045.htm>.
@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Scientists reveals an event of active ‘drip’ tectonics

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When renowned University of Toronto (U of T) geophysicist J. Tuzo Wilson cemented concepts in the emerging field of plate tectonics in the 1960s, he revolutionized the study of Earth’s physical characteristics and behaviours. Decades later, successor researchers at U of T and Istanbul Technical University have determined that a series of volcanoes and a mountain plateau across central Turkey formed not solely by the collision of tectonic plates, but instead by a massive drip and then detachment of the lower tectonic plate beneath Earth’s surface.

The researchers propose that the reason the Central Anatolian (Turkish) Plateau has risen by as much as one kilometre over the past 10 million years is because the planet’s crust and upper mantle — the lithosphere — has thickened and dripped below the region. As the lithosphere sank into the lower mantle, it first formed a basin at the surface, which later sprang up when the weight below broke off and sank further into the deeper depths of the mantle.

Cave city in volcanic rocks of uplifted Central Anatolian plateau. Credit: Russell Pysklywec

Cave city in volcanic rocks of uplifted Central Anatolian plateau.Credit: Russell Pysklywec

“It seems the heavy base of the tectonic plate has ‘dripped’ off into the mantle, leaving a massive gap in the plate beneath Central Anatolia. Essentially, by dropping this dense lithospheric anchor, there has been an upward bobbing of the entire land mass across hundreds of kilometres,” said Professor Oğuz H. Göğüş of the Eurasia Institute of Earth Sciences at Istanbul Technical University (ITU), lead author of a study reporting the findings published in Nature Communications this month.

It’s a new idea where plate shortening initially squeezed and folded a mountain belt, triggering the thickening and dripping of the deep lithosphere, and then increasing the elevation of most of central Turkey. Puzzled by the presence of such a process at a significant distance away from regular plate tectonic boundaries, the research team set about identifying why, in an area of high heating and high elevation, is the lithosphere below completely gone — something that was recently discovered from seismology.

They tested high-performance computational models against known geological and geophysical observations of the Central Anatolian Plateau, and demonstrated that a drip of lithospheric material below the surface can account for the measured elevation changes across the region.

“It’s a new variation on the fundamental concepts of plate tectonics,” said Professor Russell Pysklywec, chair of the Department of Earth Sciences at U of T and one of the study’s coauthors. “It gives us some insight into the connection between the slow circulation of near-solid rock in Earth’s mantle caused by convection currents carrying heat upwards from the planet’s interior, and observed active plate tectonics at the surface.

“This is part of the holy grail of plate tectonics — linking the two processes to understand how the crust responds to the mantle thermal engine of the planet.”

Pysklywec carried out the study with Göğüş, who received his PhD from U of T in 2010, and fellow researchers at ITU including Professor A. M. C. Şengör, and Erkan Gün of the Eurasia Institute of Earth Sciences at Istanbul Technical Institute. Gün is also now a current graduate student at U of T, supervised by Pysklywec. The research adds to decades of groundbreaking work in plate tectonics at U of T, and builds on Wilson’s seminal work.

“Tuzo Wilson is a towering figure in geophysics internationally and the person most responsible for pioneering the ideas of plate tectonics in the 1960s,” said Pysklywec. “I am pleased that we are continuing his legacy in geophysics with our work.”

While Pysklywec notes there are many locations on Earth missing its lithosphere below, he is quick to reassure that no place is in imminent danger of sinking into the mantle or boosting upwards overnight. “Our results show that the Central Anatolian Plateau rose over a period of millions of years. We’re talking about mantle fluid motions and uplift at the pace at which fingernails grow.”

Göğüş highlights the links of the tectonics with human history saying, “The findings are exciting also because of the link with the remarkable historical human activity of Central Anatolia where some of the earliest known civilizations have existed. For example, Central Anatolia is described as an elevated, dry, cold plain of Lycaonia in Strabo’s Geographika in 7 BC, and even cave paintings in the region dating to approximately 7000 BC record active volcanic eruptions on the plateau.”

  1. Oğuz H. Göğüş, Russell N. Pysklywec, A. M. C. Şengör, Erkan Gün. Drip tectonics and the enigmatic uplift of the Central Anatolian Plateau. Nature Communications, 2017; 8 (1) DOI: 10.1038/s41467-017-01611-3
University of Toronto. “Geophysicists uncover new evidence for an alternative style of plate tectonics: Canadian-Turkish collaboration reveals an event of active ‘drip’ tectonics.” ScienceDaily. ScienceDaily, 28 November 2017. <www.sciencedaily.com/releases/2017/11/171128135641.htm>.
@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev