Ring Of Fire Tectonic Plate Is Cooling – And Shrinking

The tectonic plate that dominates the Pacific “Ring of Fire” is not as rigid as most assume, and it’s getting less fiery. according to researchers at Rice University and the University of Nevada.

Rice geophysicist Richard Gordon and Corné Kreemer, an associate professor at the University of Nevada, Reno, have determined that cooling of the lithosphere — the outermost layer of Earth — makes some sections of the Pacific plate contract horizontally at faster rates than others and cause the plate to deform. Gordon said the effect detailed is most pronounced in the youngest parts of the lithosphere — about 2 million years old or less — that make up some the Pacific Ocean’s floor. They predict the rate of contraction to be 10 times faster than older parts of the plate that were created about 20 million years ago and 80 times faster than very old parts of the plate that were created about 160 million years ago.

The tectonic plates that cover Earth’s surface, including both land and seafloor, are in constant motion; they imperceptibly surf the viscous mantle below. Over time, the plates scrape against and collide into each other, forming mountains, trenches and other geological features.


Red = volcanism; yellow = quake zones; black lines =plate boundaries. Link: Tamzin Kay

On the local scale, these movements cover only inches per year and are hard to see. The same goes for deformations of the type described in the new paper, but when summed over an area the size of the Pacific plate, they become statistically significant, Gordon said.

The new calculations showed the Pacific plate is pulling away from the North American plate a little more — approximately 2 millimeters a year — than the rigid-plate theory would account for, he said. Overall, the plate is moving northwest about 50 millimeters a year.

“The central assumption in plate tectonics is that the plates are rigid, but the studies that my colleagues and I have been doing for the past few decades show that this central assumption is merely an approximation — that is, the plates are not rigid,” Gordon said. “Our latest contribution is to specify or predict the nature and rate of deformation over the entire Pacific plate.”

The researchers already suspected cooling had a role from their observation that the 25 large and small plates that make up Earth’s shell do not fit together as well as the “rigid model” assumption would have it. They also knew that lithosphere as young as 2 million years was more malleable than hardened lithosphere as old as 170 million years.

“We first showed five years ago that the rate of horizontal contraction is inversely proportional to the age of the seafloor,” he said. “So it’s in the youngest lithosphere (toward the east side of the Pacific plate) where you get the biggest effects.”

A map produced by scientists at the University of Nevada, Reno, and Rice University shows predicted velocities for sectors of the Pacific tectonic plate relative to points near the Pacific-Antarctic ridge, which lies in the South Pacific ocean. The researchers show the Pacific plate is contracting as younger sections of the lithosphere cool. Credit: Corné Kreemer and Richard Gordon

The researchers saw hints of deformation in a metric called plate circuit closure, which describes the relative motions where at least three plates meet. If the plates were rigid, their angular velocities at the triple junction would have a sum of zero. But where the Pacific, Nazca and Cocos plates meet west of the Galápagos Islands, the nonclosure velocity is 14 millimeters a year, enough to suggest that all three plates are deforming.

“When we did our first global model in 1990, we said to ourselves that maybe when we get new data, this issue will go away,” Gordon said. “But when we updated our model a few years ago, all the places that didn’t have plate circuit closure 20 years ago still didn’t have it.”

There had to be a reason, and it began to become clear when Gordon and his colleagues looked beneath the seafloor. “It’s long been understood that the ocean floor increases in depth with age due to cooling and thermal contraction. But if something cools, it doesn’t just cool in one direction. It’s going to be at least approximately isotropic. It should shrink the same in all directions, not just vertically,” he said.

A previous study by Gordon and former Rice graduate student Ravi Kumar calculated the effect of thermal contraction on vertical columns of oceanic lithosphere and determined its impact on the horizontal plane, but viewing the plate as a whole demanded a different approach. “We thought about the vertically integrated properties of the lithosphere, but once we did that, we realized Earth’s surface is still a two-dimensional problem,” he said.

For the new study, Gordon and Kreemer started by determining how much the contractions would, on average, strain the horizontal surface. They divided the Pacific plate into a grid and calculated the strain on each of the nearly 198,000 squares based on their age, as determined by the seafloor age model published by the National Geophysical Data Center.

“That we could calculate on a laptop,” Gordon said. “If we tried to do it in three dimensions, it would take a high-powered computer cluster.”

The surface calculations were enough to show likely strain fields across the Pacific plate that, when summed, accounted for the deformation. As further proof, the distribution of recent earthquakes in the Pacific plate, which also relieve the strain, showed a greater number occurring in the plate’s younger lithosphere. “In the Earth, those strains are either accommodated by elastic deformation or by little earthquakes that adjust it,” he said.

“The central assumption of plate tectonics assumes the plates are rigid, and this is what we make predictions from,” said Gordon, who was recently honored by the American Geophysical Union for writing two papers about plate movements that are among the top 40 papers ever to appear in one of the organization’s top journals. “Up until now, it’s worked really well.”

“The big picture is that we now have, subject to experimental and observational tests, the first realistic, quantitative estimate of how the biggest oceanic plate departs from that rigid-plate assumption.”

Source:Articles on Science 2.0

Thylacares brandonesis : carnivorous crustacean 435 MYA

A new species of carnivorous crustacean has been identified, which roamed the seas 435 million years ago, grasping its prey with spiny limbs before devouring it. The fossil is described and details of its lifestyle are published in the open access journal BMC Evolutionary Biology.

The fossils were discovered near Waukesha, Wisconsin, with the new species, Thylacares brandonesis, named after the Brandon Bridge Formation where it was found. It is the oldest known example of the Thylacocephala group — shrimp-like creatures, mostly from the Jurassic period, known for their bulbous eyes and multiple limbs. The muscle structure and leg morphology of the new species suggests that it used its long, claw-like appendages to catch prey in a similar way to modern remipedes, blind crustaceans still found in salt water-filled caves.

Jurassic thylacocephalan Clausocaris lithographica. Credit: Haug et al. 2014

Jurassic thylacocephalan Clausocaris lithographica.
Credit: Haug et al. 2014

Derek Briggs, Yale University, says: “This new research extends the range of this enigmatic group of fossil arthropods back to the Silurian, some 435 million years ago, and provides evidence that they belong among the crustaceans, the modern group that includes lobsters, shrimps and crabs.”

Carolin Haug, LMU Munich, said: “T. brandonensis was probably an actively hunting predator, which caught the prey with its front claws and crushed it into smaller pieces with the protrusions nearer its mouthparts.”

“This early, Silurian, example of Thylacocephala is in many ways much less extreme than the more recent Jurassic species. It still has normal-sized eyes in contrast to the very enlarged ones that came later, and shorter front claws in T. brandonensis compared to the extremely elongated ones in more recent Jurassic representatives.”

The description of the new Silurian species was part of a wider investigation into this group of fossils, including several new Jurassic specimens. Modern imaging techniques allowed the scientists to visualise new features, such as the tiny details of the T. brandonensis muscle structure. Based on these images, they created 3D models of the new species, which help us to understand the creature’s life habits.

WFS Dinosaur Diary: QUETZALCOATLUS

Quetzalcoatlus was the largest pterosaur that ever lived; in fact, this airplane-sized reptile was the largest animal ever to take to the skies, period. Here are 10 facts you may (or may not) have known about Quetzalcoatlus.

QUETZALCOATLUS

QUETZALCOATLUS

1. Quetzalcoatlus was named after an Aztec god.

Flying, feathered, reptilian deities have figured in Central American mythology since at least 500 A.D. The Aztec god Quetzalcoatl literally translates as “feathered serpent;” even though Quetzalcoatlus didn’t have feathers, the reference seemed appropriate when this giant pterosaur was first described back in 1971. (And no, this doesn’t mean that pterosaurs flew the skies during Aztec times!)

2. The wingspan of Quetzalcoatlus exceeded 30 feet.

Although its exact proportions are still a matter of dispute, there’s no doubt that Quetzalcoatlus had an enormous wingspan, exceeding 30 feet from tip to tip and possibly attaining breadths of up to 40 feet–about the size of a small private jet. By way of comparison, the largest flying bird alive today, the Andean Condor, has a wingspan of only 10 feet and weighs an order of magnitude less.

Size

Size

3. Quetzalcoatlus probably had a cold-blooded metabolism.

As was the case with all pterosaurs, the wings of Quetzalcoatlus consisted of bare, extended flaps of leathery skin. The lack of accompanying feathers implies that Quetzalcoatlus possessed a reptilian, cold-blooded metabolism, in sharp contrast to the feathered theropod dinosaurs it coexisted with during the late Cretaceous period (which may well have possessed endothermic metabolisms).

4. Quetzalcoatlus took off using both its front and hind legs…

The enormous size of Quetzalcoatlus poses some serious issues, not least of which is how it launched itself into flight. One analysis suggests that this pterosaur vaulted itself into the air with its heavily muscled front legs, and only secondarily used its long, spindly hind limbs. There’s also a case to be made that Quetzalcoatlus preferred to launch itself over the edge of steep cliffs!

Fossil

Fossil

5. …and flew without flapping its wings.

Assuming that it had a cold-blooded metabolism, Quetzalcoatlus would have been unable to continuously flap its wings while in flight (a task that requires enormous amounts of energy). According to one analysis, this pterosaur preferred to glide through the air at elevations of 10,000 to 15,000 feet and speeds as fast as 80 miles per hour, only occasionally pivoting its gigantic wings.

6. …that is, if it even flew at all.

Just because Quetzalcoatlus was a pterosaur doesn’t necessarily mean that it was capable of (or interested in) flight. Some paleontologists insist that Quetzalcoatlus was actualy adapted for life on land, and hunted its prey on two feet like a big, gangly theropod. Still, it’s unclear, evolutionarily speaking, why Quetzalcoatlus would have retained such huge wings if it spent all its time on the ground.

7. Quetzalcoatlus was an “azhdarchid” pterosaur.

Although it was certainly one of the biggest, Quetzalcoatlus wasn’t the only plus-sized pterosaur of the late Cretaceous period. Other “azhdarchid” pterosaurs, as they’re called by paleontologists, include Alanqa, Hatzegopteryx, and the poorly understood Azhdarcho; these azhdarchids were also closely related to the South American Tupuxuara and Tapejara.

8. It’s uncertain how much Quetzalcoatlus weighed…

Perhaps because paleontologists can’t quite wrap their minds around a flying reptile the size of fighter jet, there has been considerable disagreement about how much Quetzalcoatlus weighed. Early estimates posited a relatively svelte (and aerodynamic) 200 to 300 pounds, but recent studies suggest that this pterosaur may have weighed as much as a quarter of a ton.

9. …or what it ate for lunch and dinner.

When Quetzalcoatlus was first discovered, its long, narrow beak suggested that this pterosaur skimmed over the shallow seas of late Cretaceous North America, spearing fish and marine reptiles; one paleontologist has even speculated that it scavenged the corpses of deceased titanosaurs. It now seems more likely that Quetzalcoatlus hunted terrestrial animals, including small dinosaurs.

10. Quetzalcoatlus went extinct 65 million years ago.

As any Triceratops or Tyrannosaurus Rex will tell you, sheer size is no insurance policy against oblivion. Along with its fellow pterosaurs, Quetzalcoatlus went extinct at the end of the Cretaceous period, succumbing to the same environmental pressures (including a severe disruption of the food chain) as its dinosaur and marine reptile cousins in the wake of the K/T meteor impact.

Jurassic mammals were picky eaters.

New analyses of tiny fossil mammals from Glamorgan, South Wales are shedding light on the function and diets of our earliest ancestors, a team including researchers from the University of Southampton report today in the journal Nature. Mammals and their immediate ancestors from the Jurassic period (201-145 million years ago) developed new characteristics — such as better hearing and teeth capable of precise chewing.

By analysing jaw mechanics and fossil teeth, the team were able to determine that two of the earliest shrew-sized mammals, Morganucodon and Kuehneotherium, were not generalised insectivores but had already evolved specialised diets, feeding on distinct types of insects.

Morganucodon and Kuehneotherium. Credit: Pamela Gill

Morganucodon and Kuehneotherium.
Credit: Pamela Gill

Lead author, Dr Pamela Gill of the University of Bristol, said: “None of the fossils of the earliest mammals have the sort of exceptional preservation that includes stomach contents to infer diet, so instead we used a range of new techniques which we applied to our fossil finds of broken jaws and isolated teeth. Our results confirm that the diversification of mammalian species at the time was linked with differences in diet and ecology.”

The team used synchrotron X-rays and CT scanning to reveal in unprecedented detail the internal anatomy of these tiny jaws, which are only 2cm in length. As the jaws are in many pieces, the scans were ‘stitched together’ to make a complete digital reconstruction. Finite element modelling, the same technique used to design hip joints and bridges, was used to perform a computational analysis of the strength of the jaws. This showed that Kuehneotherium and Morganucodon had very different abilities for catching and chewing prey.

Study co-author, Dr Neil Gostling from the University of Southampton, said: “The improvement in CT scanning, both in the instrumentation, at Light Source at the Paul Scherrer Institute in Switzerland where we scanned or even the µ-VIS Centre at Southampton, along with access for research of this kind, allows us to make inroads into understanding the biology and the ecology of animals long dead. The questions asked of the technology do not produce ‘speculation’, rather the results show a clearly defined answer based on direct comparison to living mammals. This would not be possible without the computational techniques we have used here.”

Using an analysis previously carried out on the teeth of present-day, insect-eating bats, the researchers found that the teeth of Morganucodon and Kuehneotherium had very different patterns of microscopic pits and scratches, known as ‘microwear’. This indicated they were eating different things with Morganucodon favouring harder, crunchier food items such as beetles while Kuehneotherium selected softer foods such as scorpion flies which were common at the time.

Team leader, Professor Emily Rayfield from the University of Bristol, added: “This study is important as it shows for the first time that the features that make us unique as mammals, such as having only one set of replacement teeth and a specialised jaw joint and hearing apparatus, were associated with the very earliest mammals beginning to specialise their teeth and jaws to eat different things.”

Courtesy: University of Southampton. “Jurassic mammals were picky eaters, new study finds.” ScienceDaily. ScienceDaily, 20 August 2014.

Prehistoric crocodilian diversity depends on sea temperature

The ancestors of today’s crocodiles colonised the seas during warm phases and became extinct during cold phases, according to a new Anglo-French study which establishes a link between marine crocodilian diversity and the evolution of sea temperature over a period of more than 140 million years.

The research, led by Dr Jeremy Martin from the Université de Lyon, France and formerly from the University of Bristol, UK is published this week in Nature Communications.

Today, crocodiles are ‘cold-blooded’ animals that mainly live in fresh waters but two notable exceptions, Crocodylus porosus and Crocodylus acutus venture occasionally into the sea. Crocodiles occur in tropical climates, and they are frequently used as markers of warm conditions when they are found as fossils.

This is a marine crocodilian, here a dyrosaurid, swimming in the warm surface waters during the end of the Cretaceous period. Credit: Guillaume Suan

This is a marine crocodilian, here a dyrosaurid, swimming in the warm surface waters during the end of the Cretaceous period.
Credit: Guillaume Suan

While only 23 species of crocodiles exist today, there were hundreds of species in the past. On four occasions in the past 200 million years, major crocodile groups entered the seas, and then became extinct. It is a mystery why they made these moves, and equally why they all eventually went extinct. This new study suggests that crocodiles repeatedly colonized the oceans at times of global warming.

Lead author of the report, Dr Jeremy Martin said: “We thought each of these evolutionary events might have had a different cause. However, there seems to be a common pattern.”

Dr Martin, with a team of paleontologists and geochemists from the Université de Lyon and the University of Bristol, compared the evolution of the number of marine crocodilian fossil species to the sea temperature curve during the past 200 million years. This temperature curve, established using an isotopic thermometer, is widely applied for reconstruction of past environmental conditions and in this case, is based on the isotopic composition of the oxygen contained in the fossilised remains of fossil marine fish (bone, teeth, scales).

Co-author, Christophe Lécuyer explained: “According to this method, it is possible to calculate the temperature of the water in which these fish lived by applying an equation linking the isotopic composition of the fossilised remains to the temperature of mineralisation of their skeleton. The seawater temperatures derived from the composition of fish skeleton thus corresponds to the temperature of water in which the marine crocodiles also lived.”

The results show that colonisation of the marine environment about 180 million years ago was accompanied by a period of global warming of the oceans. These first marine crocodilians became extinct about 25 million years later, during a period of global freezing. Then, another crocodilian lineage appeared and colonised the marine environment during another period of global warming.

The evolution of marine crocodilians is therefore closely tied to the temperature of their medium, and shows that their evolution and their lifestyle, as in modern crocodilians, are constrained by environmental temperatures.

Nevertheless, one fossil lineage does not appear to follow this trend. Jurassic metriorhynchoids did not go extinct during the cold spells of the early Cretaceous, unlike the teleosaurids, another group of marine crocodilians. Quite surprisingly, metriorhynchoids only disappeared a few million years later. This exception will certainly provide grounds for new research, particularly into how the biology of this group adapted to life in the pelagic environment.

Professor Michael Benton from the University of Bristol, another co-author of the study, said: “This work illustrates a case of the impact of climate change on the evolution of animal biodiversity, and shows that for crocodilians, warming phases of our earth’s history constitute ideal opportunities to colonise new environments.”

Source:Jeremy E. Martin, Romain Amiot, Christophe Lécuyer, Michael J. Benton. Sea surface temperature contributes to marine crocodylomorph evolution. Nature Communications, 2014; 5 DOI: 10.1038/ncomms5658

Caiuajara dobruskii:New pterosaur species found

A flying reptile whose head was topped with a big bony crest shaped like the sail of a yacht swooped through the skies over Brazil roughly 90 million years ago.

Scientists announced on Wednesday the remarkable discovery of about 50 fossilized skeletons of a creature called Caiuajara dobruskii, a type of flying reptile known as a pterosaur that lived alongside the dinosaurs, at a site in southern Brazil.

These pterosaurs, whose wingspans measured up to nearly 2.35 meters, inhabited a lakeside oasis in a large desert region during the Cretaceous Period, living in vibrant colonies with others of the same species of all ages, they said.

“This helps us to have a glimpse on the anatomical variation achieved by this species from young to old,” said Alexander Kellner, a paleontologist with Brazil’s National Museum at the Federal University of Rio de Janeiro, who led the study.

Many pterosaurs, especially the later ones, boasted elaborate and sometimes large head crests. Caiuajara’s head was topped with a big triangular crest that looked like “a bony sail,” according to Kellner. “It looks bizarre,” he said.

There is no indication that the crest was limited to either males or females, but it appears to have become ever larger relative to the rest of the body as the pterosaur matured.

“The size of the crest was small in young animals and very large in older ones,” Kellner added.

Pterosaurs were Earth’s first flying vertebrates, with birds and bats making their appearances much later. They thrived from about 220 million years ago to 65 million years ago, when they were wiped out by the asteroid that also doomed the dinosaurs.

The new pterosaur Caiuajara dobruskii had a sail-like crest that became larger relative to the rest of the body as the pterosaur matured. (Maurilio Oliveira/Museu Nacional-UFRJ)

The new pterosaur Caiuajara dobruskii had a sail-like crest that became larger relative to the rest of the body as the pterosaur matured. (Maurilio Oliveira/Museu Nacional-UFRJ)

The researchers described 47 skeletons in their study published in the scientific journal PLOS ONE and said they have identified 10 more not described in the paper. They said this species lived about 80 to 90 million years ago.

Caiuajara was toothless and most likely a fruit eater, Kellner said. The skeletons of the juveniles strongly suggested they could fly at a very young age, Kellner added.

Knowledge about pterosaurs has been spotty, with their fragile skeletons not lending themselves well to fossilization. The sheer number of Caiuajara individuals discovered and their variety of ages have made it one of the best understood pterosaurs ever found, the researchers said.

Chinese scientists in June said they had unearthed no fewer than 40 adult individuals of another newly identified pterosaur species as well as five pterosaur eggs — very rare indeed — preserved beautifully in three dimensions.

No eggs of Caiuajara have been found at the site in Brazil. “Not yet. But one is allowed to dream, correct?” said Kellner.

New species of pterosaur found in mass grave

A rare stash of thousands of ancient bones found in Brazil has turned in a magnificent find: over 47 skeletons of a single, new species of Upper Cretaceous pterosaur.

Discovered in an old lake deposit on the outskirts of Cruzeiro do Oeste in the southern state of Parana, the bones are unusual for two reasons: firstly, that pterosaur bones had never been found in the southern part of Brazil, with all other pterosaur material found in the northeast.

As for how the grave came to be, evidence suggests that the site — an oasis — was a habitat for the pterosaurs for a very long time, and they did not all die simultaneously.

“Episodic events (e.g., desert storms) likely carried the disarticulated and partially articulated skeletons to the bottom of the lake where they got eventually preserved. The presence of three main levels of accumulation in a section of less than one meter suggests that this region was home to pterosaur populations for an extended period of time,” the paper reads.

“It is also plausible that Caiuajara was a migratory pterosaur that visited this area from time to time, although the first possibility is favoured here. The causes of death remain unknown, although similarities with dinosaur drought-related mortality are striking. However, it is also possible that desert storms could have been responsible for the occasional demise of these pterosaurs.”

Secondly, the size of the cache, found over a space of about 20 square metres, is deeply impressive. Pterosaurs seem to have lived on the coast, and recovered remains are usually limited to fragments of a single specimen. Although the researchers confirmed 47 individuals, they estimate the actual number to be well into the hundreds.

“Most pterosaurs are known from ancient coastal or shallow marine deposits and the number of species that lived deep inside the continents is limited, particularly from desert environments,” the research paper, published in the journal PLOS One, reads.

The new species has been named Caiuajara dobruskii, and the cache contained bones from several stages of development, from young to adult, with wingspans ranging from 0.65 metres to 2.35 metres. The pterosaurs’ heads are also adorned with a large crest, which grew in prominence as the animals matured. The size of the grave suggests that they were a social species, living and flying in colonies, developing flight from a very young age.

As for how the grave came to be, evidence suggests that the site — an oasis — was a habitat for the pterosaurs for a very long time, and they did not all die simultaneously.

“Episodic events (e.g., desert storms) likely carried the disarticulated and partially articulated skeletons to the bottom of the lake where they got eventually preserved. The presence of three main levels of accumulation in a section of less than one meter suggests that this region was home to pterosaur populations for an extended period of time,” the paper reads.

“It is also plausible that Caiuajara was a migratory pterosaur that visited this area from time to time, although the first possibility is favoured here. The causes of death remain unknown, although similarities with dinosaur drought-related mortality are striking. However, it is also possible that desert storms could have been responsible for the occasional demise of these pterosaurs.”

Amber offers new views of a lost world

Scientists are searching through a massive collection of 20-million-year-old amber found in the Dominican Republic more than 50 years ago, and the effort is yielding fresh insights into ancient tropical insects and the world they inhabited.

When the collection is fully curated, a task that will take many years, it will be the largest unbiased Dominican amber collection in the world, the researchers report.

Sir David Attenborough narrates and appears in a video about the digital curation of a 20-million-year-old amber collection at the Illinois Natural History Survey at Illinois. (See link to video in paragraph 9.) - IMAGE and VIDEO by Kaitlin and Kevin Southworth

Sir David Attenborough narrates and appears in a video about the digital curation of a 20-million-year-old amber collection at the Illinois Natural History Survey at Illinois. IMAGE and VIDEO by Kaitlin and Kevin Southworth

Perhaps the most striking discovery thus far is that of a pygmy locust, a tiny grasshopper the size of a rose thorn that lived 18- to 20-million years ago and fed on moss, algae and fungi. The specimen is remarkable because it represents an intermediate stage of evolution in the life of its subfamily of locusts (known as the Cladonotinae). The most ancient representatives of this group had wings, while modern counterparts do not. The newly discovered locust has what appear to be vestigial wings – remnant structures that had already lost their primary function.

The discovery is reported in the journal ZooKeys.

“Grasshoppers are very rare in amber and this specimen is extraordinarily well-preserved,” said Sam Heads, a paleontologist at the Illinois Natural History Survey, a division of the Prairie Research Institute at the University of Illinois.

Heads, laboratory technician Jared Thomas and study co-author Yinan Wang found the new specimen a few months after the start of their project to screen more than 160 pounds of Dominican amber collected in the late 1950s by former INHS entomologist Milton Sanderson. Sanderson described several specimens from the collection in a paper in Science in 1960, a report that inspired a generation of scientists to seek out and study Dominican amber, Heads said.

Heads has named the new pygmy locust Electrotettix attenboroughi, the genus name a combination of electrum (Latin from Greek, meaning “amber”) and tettix (Greek, meaning “grasshopper”). The species is named for Sir David Attenborough, a British naturalist and filmmaker (not to be confused with Richard Attenborough, David’s actor brother who appeared in the movie “Jurassic Park”).

“Sir David has a personal interest in amber, and also he was one of my childhood heroes and still is one of my heroes and so I decided to name the species in his honor — with his permission of course,” Heads said. (Attenborough narrates and appears in a new video about the Sanderson collection and the specimen that bears his name.)

The process of screening the amber is slow and painstaking. Much of the amber is clouded with oxidation, and the researchers must carefully cut and polish “windows” in it to get a good look at what’s inside. In addition to the pygmy locust, Heads and his colleagues have found mating flies, stingless bees, gall midges, Azteca ants, wasps, bark beetles, mites, spiders, plant parts and even a mammal hair.

The pygmy locust was found in a fragment that also contained wasps, ants, midges, plant remnants and fungi. Such associations are rich in information, Heads said, offering clues about the creatures’ physiological needs and the nature of their habitat.

“Fossil insects can provide lots of insight into the evolution of specific traits and behaviors, and they also tell us about the history of the time period,” Heads said. “They’re a tremendous resource for understanding the ancient world, ancient ecosystems and the ancient climate – better even, perhaps, than dinosaur bones.”

Note: This story has been adapted from a news release issued by the University of Illinois at Urbana-Champaign

Kulindadromeus zabaikalicus suggest all dinosaurs could have been feathered

The first ever example of a plant-eating dinosaur with feathers and scales has been discovered in Russia. Previously only flesh-eating dinosaurs were known to have had feathers, so this new find raises the possibility that all dinosaurs could have been feathered.

The new dinosaur, named Kulindadromeus zabaikalicus as it comes from a site called Kulinda on the banks of the Olov River in Siberia, is described in a paper recently published in Science.

Kulindadromeus shows epidermal scales on its tail and shins, and short bristles on its head and back. The most astonishing discovery, however, is that it also has complex, compound feathers associated with its arms and legs.

Kulindadromeus zabaikalicus in its lacustrine environment. Credit: Andrey Atuchin

Kulindadromeus zabaikalicus in its lacustrine environment.
Credit: Andrey Atuchin

Birds arose from dinosaurs over 150 million years ago so it was no surprise when dinosaurs with feathers were found in China in 1996. But all those feathered dinosaurs were theropods, flesh-eating dinosaurs that include the direct ancestors of birds.

Lead author Dr Pascal Godefroit from the Royal Belgian Institute of Natural History in Brussels said: “I was really amazed when I saw this. We knew that some of the plant-eating ornithischian dinosaurs had simple bristles, and we couldn’t be sure whether these were the same kinds of structures as bird and theropod feathers. Our new find clinches it: all dinosaurs had feathers, or at least the potential to sprout feathers.”

The Kulinda site was found in summer 2010 by Professor Dr Sofia Sinitsa from the Institute of Natural Resources, Ecology and Cryology SB RAS in Chita, Russia. In 2013, the Russian-Belgian team excavated many dinosaur fossils, as well as plant and insect fossils.

The feathers were studied by Dr Maria McNamara (University of Bristol and University College, Cork) and Professor Michael Benton (University of Bristol), who has also worked on the feathers of Chinese dinosaurs, and Professor Danielle Dhouailly (Université Joseph Fourier in Grenoble, France) who is a specialist on the development of feathers and scales in modern reptiles and birds.

Dr McNamara said: “These feathers are really very well preserved. We can see each filament and how they are joined together at the base, making a compound structure of six or seven filaments, each up to 15mm long.”

Professor Dhouailly said: “Developmental experiments in modern chickens suggest that avian scales are aborted feathers, an idea that explains why birds have scaly legs. The astonishing discovery is that the molecular mechanisms needed for this switch might have been so clearly related to the appearance of the first feathers in the earliest dinosaurs.”

Kulindadromeus was a small plant-eater, only about 1m long. It had long hind legs and short arms, with five strong fingers. Its snout was short, and its teeth show clear adaptations to plant eating. In evolutionary terms, it sits low in the evolutionary tree of ornithischian dinosaurs. There are six skulls and several hundred partial skeletons of this new dinosaur at the Kulinda locality.

This discovery suggests that feather-like structures were likely widespread in dinosaurs, possibly even in the earliest members of the group. Feathers probably arose during the Triassic, more than 220 million years ago, for purposes of insulation and signalling, and were only later co-opted for flight. Smaller dinosaurs were probably covered in feathers, mostly with colourful patterns, and feathers may have been lost as dinosaurs grew up and became larger.

Source: Bristol University. “Fossils found in Siberia suggest all dinosaurs could have been feathered.” ScienceDaily. ScienceDaily, 30 July 2014. <www.sciencedaily.com/releases/2014/07/140730050516.htm>.