Exploring Prehistoric Life

Dinosaur-Era Bird Found Trapped in Amber

Monday, February 5, 2018

The amber containing the dinosaur-era bird had been polished partway through the body, allowing researchers to peer inside the skull and chest cavity and chemically map its exposed soft tissues. PHOTOGRAPH BY R.C. MCKELLAR, ROYAL SASKATCHEWAN MUSEU

The squashed remains of a small bird that lived 99 million years ago have been found encased in a cloudy slab of amber from Myanmar (Burma). While previous birds found in Burmese amber have been more visually spectacular, none of them have contained as much of the skeleton as this juvenile, which features the back of the skull, most of the spine, the hips, and parts of one wing and leg.

The newfound bird is also special because researchers can more clearly see the insides of the young prehistoric creature, says study co-author Ryan McKellar of the Royal Saskatchewan Museum in Regina, Canada.

“The amber is turbid, with lots of little wood particulates. It looks like it was produced on or near the forest floor,” McKellar says. This means the external view of the bird isn’t great, but the interior is much more exciting.

“When it was being prepared in Myanmar, they polished through the front half of the specimen, which gave us an exposed view into the chest cavity and the skull,” McKellar says.

The discovery adds to a remarkable collection of Cretaceous-period fossils from the amber deposits in northern Myanmar’s Hukawng Valley. In the past few years, the region has also yielded several beautiful bird wings, the spectacular feathered tail of a small carnivorous dinosaur, and the outline of an entire hatchling bird. In December, researchers even revealed ticks in amber that may have feasted on dinosaurs.

“This Myanmar fossil deposit is clearly game-changing. It’s arguably the more important breakthrough for understanding bird evolution right now,” says Julia Clarke, an expert on the evolution of birds and flight at the University of Texas at Austin.

“We used to think we’d never have a whole bird in Cretaceous amber, but now we have multiple examples.”


Lida Xing, lead author of the paper detailing the specimen in the journal Science Bulletin, says that when he first saw the newfound bird being sold for jewelry in Myanmar in 2015, his heart began to beat very fast.

The team was lucky to acquire the bird for the Dexu Institute of Paleontology in Chaozhou, China. Birds in amber can sometimes sell for up to $500,000, putting them beyond the reach of scientists, says Xing, a paleontologist at the China University of Geosciences in Beijing.

He estimates that this is only the second bird in Burmese amber that’s been described by scientists and published in a journal. But he thinks as many as six have been discovered so far, around half of which have disappeared into the hands of private collectors.

Based on their analysis, supported in part by National Geographic, the team says that the young bird fell into the Cretaceous tree resin either dead or alive, and moisture caused the resin to foam slightly, later creating the cloudy amber. Some of the bones and soft tissues were weathered away, and sediment got trapped inside the spaces.

An illustration shows the young Cretaceous bird trapped in tree resin, which would eventually fossilize into amber.  ILLUSTRATION BY CHEUNG CHUNG TAT

“A subsequent resin flow sealed the remains to protect them from further weathering or dissolution, but the amber was later squished, shattering many of the bones,” says McKellar. “All of this is now trapped in a wafer of amber about as large as a belt buckle.”

The bird itself is around 2.4 inches long and is perhaps slightly older than the 1.8-inch hatchling bird described last year. The structure of its feathers and skeleton suggests it was an enantiornithine, a type of primitive bird that went extinct with the non-avian dinosaurs 66 million years ago.

“Even though they are hatchlings, they already have a full set of flight feathers,” McKellar says. “They have a weakly developed rachis, or central shaft, so they may not have been excellent flyers.”

In life, the bird would have had teeth in its beak and would have been dark chestnut or walnut in color, with fuzzy feathers on its head and neck.


“It’s always exciting when a vertebrate fossil is found in amber, especially Cretaceous amber,” says George Poinar, a paleobiologist at Oregon State University in Corvallis, whose research on fossilized insects in amber inspired the plot of Jurassic Park.

Assigning it to the enantiornithine birds makes sense, he adds, as they were common at that time. But it’s a pity “that the two diagnostic features of that family are missing: the toothed beak and clawed fingers on the wings.”

Poinar speculates that the fledgling may have been attacked by a predator and knocked out of the nest into resin oozing from the same tree, and that some of the plant fragments and a cockroach also found trapped in the amber piece may have originated in the nest.

“Cockroaches are general scavengers, and finding them in nesting material would not be a surprise,” he says.

With time and luck, McKellar says, the team hopes to have a whole growth series of enantiornithine birds in Burmese amber. There’s certainly no shortage of raw material to comb through—in 2015 alone, an estimated 10 tons of amber were extracted from the Hukawng Valley.


Source: news.nationalgeographic.com

Toward end of Ice Age, Human Beings Witnessed Fires Larger than Dinosaur Killers

Saturday, February 3, 2018

New research shows that some 12,800 years ago, an astonishing 10 percent of the Earth's land surface, or about 10 million square kilometers, was consumed by fires. Credit: © Oran Tantapakul / Fotolia

On a ho-hum day some 12,800 years ago, the Earth had emerged from another ice age. Things were warming up, and the glaciers had retreated.

Out of nowhere, the sky was lit with fireballs. This was followed by shock waves.

Fires rushed across the landscape, and dust clogged the sky, cutting off the sunlight. As the climate rapidly cooled, plants died, food sources were snuffed out, and the glaciers advanced again. Ocean currents shifted, setting the climate into a colder, almost "ice age" state that lasted an additional thousand years.

Finally, the climate began to warm again, and people again emerged into a world with fewer large animals and a human culture in North America that left behind completely different kinds of spear points.

This is the story supported by a massive study of geochemical and isotopic markers just published in the Journal of Geology.

The results are so massive that the study had to be split into two papers.

"Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact ~12,800 Years Ago" is divided into "Part I: Ice Cores and Glaciers" and "Part 2: Lake, Marine, and Terrestrial Sediments."

The paper's 24 authors include KU Emeritus Professor of Physics & Astronomy Adrian Melott and Professor Brian Thomas, a 2005 doctoral graduate from KU, now at Washburn University.

"The work includes measurements made at more than 170 different sites across the world," Melott said.

The KU researcher and his colleagues believe the data suggests the disaster was touched off when Earth collided with fragments of a disintegrating comet that was roughly 62 miles in diameter -- the remnants of which persist within our solar system to this day.

"The hypothesis is that a large comet fragmented and the chunks impacted the Earth, causing this disaster," said Melott. "A number of different chemical signatures -- carbon dioxide, nitrate, ammonia and others -- all seem to indicate that an astonishing 10 percent of the Earth's land surface, or about 10 million square kilometers, was consumed by fires."

According to Melott, analysis of pollen suggests pine forests were probably burned off to be replaced by poplar, which is a species that colonizes cleared areas.

Indeed, the authors posit the cosmic impact could have touched off the Younger Dryas cool episode, biomass burning, late Pleistocene extinctions of larger species and "human cultural shifts and population declines."

"Computations suggest that the impact would have depleted the ozone layer, causing increases in skin cancer and other negative health effects," Melott said. "The impact hypothesis is still a hypothesis, but this study provides a massive amount of evidence, which we argue can only be all explained by a major cosmic impact."

Story Source:

Materials provided by University of KansasNote: Content may be edited for style and length.

Journal References:

  1. Wendy S. Wolbach, Joanne P. Ballard, Paul A. Mayewski, Victor Adedeji, Ted E. Bunch, Richard B. Firestone, Timothy A. French, George A. Howard, Isabel Israde-Alcántara, John R. Johnson, David Kimbel, Charles R. Kinzie, Andrei Kurbatov, Gunther Kletetschka, Malcolm A. LeCompte, William C. Mahaney, Adrian L. Melott, Abigail Maiorana-Boutilier, Siddhartha Mitra, Christopher R. Moore, William M. Napier, Jennifer Parlier, Kenneth B. Tankersley, Brian C. Thomas, James H. Wittke, Allen West, James P. Kennett. Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact ∼12,800 Years Ago. 1. Ice Cores and GlaciersThe Journal of Geology, 2018; 000 DOI: 10.1086/695703
  2. Wendy S. Wolbach, Joanne P. Ballard, Paul A. Mayewski, Andrew C. Parnell, Niamh Cahill, Victor Adedeji, Ted E. Bunch, Gabriela Domínguez-Vázquez, Jon M. Erlandson, Richard B. Firestone, Timothy A. French, George Howard, Isabel Israde-Alcántara, John R. Johnson, David Kimbel, Charles R. Kinzie, Andrei Kurbatov, Gunther Kletetschka, Malcolm A. LeCompte, William C. Mahaney, Adrian L. Melott, Siddhartha Mitra, Abigail Maiorana-Boutilier, Christopher R. Moore, William M. Napier, Jennifer Parlier, Kenneth B. Tankersley, Brian C. Thomas, James H. Wittke, Allen West, James P. Kennett. Extraordinary Biomass-Burning Episode and Impact Winter Triggered by the Younger Dryas Cosmic Impact ∼12,800 Years Ago. 2. Lake, Marine, and Terrestrial SedimentsThe Journal of Geology, 2018; 000 DOI: 10.1086/695704



Wahlisaurus massarae: Paleontologists Find 200-Million-Year-Old Ichthyosaur Fossil

Saturday, February 3, 2018

Reconstruction of Wahlisaurus massarae. Image credit: James McKay.

The 200 million-year-old specimen is only the second known example of Wahlisaurus massarae, a species of ichthyosaur announced recently by a University of Manchester paleontologist.

Ichthyosaurs were predatory sea-going reptiles that ranged in size from 1 to 69 feet (0.3-21 m) long. They swam the world’s oceans for millions of years during the Triassic, Jurassic and Cretaceous periods.

Despite their profound adaptations to the aquatic realm, these reptiles disappeared about 30 million years before the end-Cretaceous mass extinction (65 million years ago) that marked the end for dinosaurs and the beginning of the age of mammals.

In 2016, a paleontologist and honorary scientist at the University of Manchester, Dean Lomax, described an ichthyosaur skeleton that he had examined in the collections of Leicester’s New Walk Museum and Art Gallery.

He spotted several unusual features of the bones and determined that the features were unique and represented a completely new species, Wahlisaurus massarae.

“When Wahlisaurus massarae was announced, I was a little nervous about what other paleontologists would make of it, considering the new species was known only from a single specimen,” Lomax said.

“As a scientist you learn to question almost everything, and be as critical as you can be.”

“My analysis suggested it was something new, but some paleontologists questioned this and said it was just ‘variation’ of an existing species.”

Photograph of Dean Lomax (left), Simon Carpenter (middle) and Deborah Hutchinson with the new specimen of Wahlisaurus massarae. Image credit: University of Manchester.

In the new study, Lomax teamed up with New Walk Museum paleontologist Mark Evans and Simon Carpenter, fossil collector of Somerset.

The study focuses on a specimen Lomax identified in Simon’s private collection, which is an almost complete coracoid bone (part of the pectoral girdle) that has exactly the same unique features of the same bone in Wahlisaurus massarae.

“You can only imagine my sheer excitement to find a specimen of Wahlisaurus massarae,” Lomax said.

“It was such a wonderful moment. When you have just one specimen, ‘variation’ can be called upon, but when you double the number of specimens you have it gives even more credibility to your research.”

The new discovery is from a time known as the Triassic-Jurassic boundary, right after a world-wide mass extinction.

For these reasons, the authors have been unable to determine exactly whether the ichthyosaur was latest Triassic or earliest Jurassic in age, although it is roughly 200 million-year-old.

The team’s results will be published in the Geological Journal.


D.R. Lomax et al. 2018. An ichthyosaur from the UK Triassic-Jurassic boundary: A second specimen of the leptonectid ichthyosaur Wahlisaurus massaraeLomax 2016. Geological Journal, in press; doi: 10.1002/gj.3155

Source: www.sci-news.com

Dinosaur Age Meets the Space Age

Saturday, February 3, 2018

Detail view of a cast from the sandstone slab imprinted with more than 70 dinosaur and mammal tracks discovered at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Credit: NASA's Goddard Space Flight Center/Rebecca Roth

A slab of sandstone discovered at NASA's Goddard Space Flight Center contains at least 70 mammal and dinosaur tracks from more than 100 million years ago, according to a new paper published Jan. 31 in the journal Scientific Reports. The find provides a rare glimpse of mammals and dinosaurs interacting.

The tracks were discovered by Ray Stanford—a local dinosaur track expert whose wife, Sheila, works at Goddard. After dropping off Sheila at work one day in 2012, Stanford spotted an intriguing rock outcropping behind Shelia's building on a hillside. Stanford parked his car, investigated, and found a 12-inch-wide dinosaur track on the exposed rock. Excavation revealed that the slab was the size of a dining room table and examination in the ensuing years found that it was covered in preserved tracks.

The remarkable Goddard specimen, about 8 feet by 3 feet in size, is imprinted with nearly 70 tracks from eight species, including squirrel-sized mammals and tank-sized . Analysis suggests that all of the tracks were likely made within a few days of each other at a location that might have been the edge of a wetland, and could even capture the footprints of predator and prey.

"The concentration of  tracks on this site is orders of magnitude higher than any other site in the world," said Martin Lockley, paleontologist with the University of Colorado, Denver, a co-author on the new paper. Lockley began studying footprints in the 1980s, and was one of the first to do so. "I don't think I've ever seen a slab this size, which is a couple of square meters, where you have over 70 footprints of so many different types. This is the mother lode of Cretaceous mammal tracks."

By Jonathan Corum | Photograph by (and slab illustration modified from) Stanford et al., Scientific Reports

After Stanford's initial find, Stephen J. Godfrey, curator of paleontology at the Calvert Marine Museum, coordinated the excavation of the slab and produced the mold and cast that formed the basis of the scientific work.

The first track Stanford found was of a nodosaur—"think of them as a four-footed tank," Stanford said. Subsequent examination revealed a baby nodosaur print beside and within the adult print, likely indicating that they were traveling together. The other  include: a sauropod, or long-necked plant-eater; small theropods, crow-sized carnivorous dinosaurs closely related to the Velociraptor and Tyrannosaurus rex; and pterosaurs, a group of flying reptiles that included pterodactyls.

"It's a time machine," Stanford said. "We can look across a few days of activity of these animals and we can picture it. We see the interaction of how they pass in relation to each other. This enables us to look deeply into ancient times on Earth. It's just tremendously exciting."

The dinosaur tracks are impressive, but it is the collection of mammal tracks that make the slab significant. At least 26 mammal tracks have been identified on the slab since the 2012 discovery—making it one of two known sites in the world with such a concentration of prints. Furthermore, the slab also contains the largest mammal track ever discovered from the Cretaceous. It is about four inches square, or the size of a raccoon's prints.

Lockley and Stanford said most of these ancient footprints belong to what we would consider small mammals—animals the size of squirrels or prairie dogs. Most Cretaceous mammals discovered to date have been the size of rodents, their size usually determined only from their teeth. "When you have only teeth, you have no idea what the animals looked like or how they behaved," Lockley said.

Lockley and Stanford believe the wide diversity and number of tracks show many of the animals were in the area actively feeding at the same time. Perhaps the mammals were feeding on worms and grubs, the small carnivorous dinosaurs were after the mammals, and the pterosaurs could have been hunting both the mammals and the small dinosaurs.

Detail view of a cast from the sandstone slab imprinted with more than 70 dinosaur and mammal tracks discovered at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Credit: NASA's Goddard Space Flight Center/Rebecca Roth

The parallel trackway patterns made by four crow-sized carnivorous dinosaurs suggests they were hunting or foraging as a group. "It looks as if they were making a sweep across the area," Lockley said.

Several of the mammal tracks occur in pairs, representing hind feet. "It looks as if these squirrel-sized animals paused to sit on their haunches," Lockley said. The team gave the new formal scientific name of Sederipes goddardensis, meaning sitting traces from Goddard Space Flight Center, to this unusual configuration of tracks.

"We do not see overlapping tracks—overlapping tracks would occur if multiple tracks were made over a longer period while the sand was wet," said Compton Tucker, a Goddard Earth scientist who helped with the excavation, coordinated bringing in multiple scientists to study the tracks, and has worked to create a display of the cast in Goddard's Earth science building. "People ask me, 'Why were all these tracks in Maryland?' I reply that Maryland has always been a desirable place to live."

What is now Maryland would have been a much hotter, swampier place in the Cretaceous, when sea levels would have been hundreds of feet higher than today. As scientists continue to study the slab and compare the tracks to others found in the area and around the world, they will continue to discover more about prehistoric life that existed here.

"This could be the key to understanding some of the smaller finds from the area, so it brings everything together," Lockley said. "This is the Cretaceous equivalent of the Rosetta stone."

Source: https://phys.org

Young Tourist Helps Edmonton Researchers in Discovery of Rare Colombian Fish Fossil

Saturday, February 3, 2018

This perfectly-preserved ancient fish fossil was discovered embedded in the flagstones of an old Colombian monastery by a young boy. (Oksana Vernygora)

Edmonton paleontologists are crediting a keen-eyed tourist for spotting a never-before-seen fish fossil in flagstones outside a Colombian monastery.

The perfectly-preserved "lizard fish" specimen is an estimated 90 million years old and has no modern relatives. The extremely rare specimen is the first fossil of its kind to ever be found in South America. 

"This fossil was one of those serendipitous, unexpected findings," said paleontologist Javier Luque, a PhD candidate at the University of Alberta's biological sciences department and co-author of the research paper on the find.


'Once in a lifetime discovery'

"It was kind of a once-in-a-lifetime discovery, in many ways."

The discovery was made in 2015 at the Monastery of La Candelaria by a young boy who spotted the outline of a fish in one of the flagstones outside the 17th-century building.

Curious about the strange rock, the boy snapped a photo and shared it with staff at Centro de Investigaciones Paleontologicas, a museum in nearby Ráquira, Boyaca. Workers there recognized it as a fossil right away and shared the discovery with the University of Alberta.

The long-jawed 'lizard fish' would have thrived in the oceans that once covered Colombia. (Oksana Vernygora)

The flagstone had been part of the busy pathway for more than 15 years, said Luque. 

"A kid was just walking around saw what he thought was a fish and sure enough, he took a photo with the inquiring mind of a child," Luque said.

"It was a fossil fish, perfectly preserved in two dimensions, just laying down, weathering as people were walking on top of it for so many years."


'Shocking to see'

The museum and the university often partner on fossil finds in the area, said Luque.

After getting the call, a team of U of A researchers joined the local paleontologists in retracing the boy's steps to locate and lift the stone for further examination.

Researchers were able to trace the origins of the fossil-bearing flagstone to a nearby abandoned quarry from where locals extracted slabs for construction several years ago.

The research paper on the fossil was recently published in the Journal of Systematic Paleontology.  It was co-authored by Oksana Vernygora, a fellow PhD candidate at the U of A led the research with assistance from her supervisor, and Allison Murray, a professor of biological sciences.

The rocks date from the Late Cretaceous period, and were deposited at a time when most of the northern Andes was underwater, which accounts for a rich record of marine life in the heart of the Andes mountains. 

"It's an entirely new group of fossil fish from the Cretaceous period in South America," Luque said. 


It has been named Candelarhynchus padillai, which combines  'Candelaria,' the name of the monastery where the fossil was discovered, and the Greek word for nose 'rhynchos,' due to its peculiar long and slender needle-like face.


And while the fossil's backstory has largely been explained, the fish tale has one more mystery.

Researchers lost touch with the boy who found the fossil. They have only his name.

They are hoping, with the recent publication of the research, the boy might eventually come forward, so they can give him proper credit.

"We certainly will make sure we properly acknowledge this discovery," Luque said. "It was the keen eye of a young kid that was able to recognize the shape of a fossil that we were not able to see for so many years. 

"It gives a beautiful message about keeping curious … and being able to see the world with fresh eyes."

Source: www.cbc.ca


The Lost Continent of Laramidia

Tuesday, February 13, 2018

North America, 76 million years ago

In this article, we discuss the nature of North America in the Late Cretaceous Period. Between 100 and 70 million years ago, the entire continent was divided by a shallow sea. This sea was once filled with colossal marine lizards, long-necked plesiosaurs, toothed birds, and the occasional diving Pteranodon. The sea divided the land into two smaller continents: Appalachia in the east and Laramidia in the west. As residents of the eastern United States, we are saddened by the meager dinosaur fossils (so far) discovered in the east. However, the vast and exposed formations in the west tell an amazing story.

Fossil-bearing formations dot the landscape of Laramidia, from the North Slope of Alaska down into Mexico. Each formation exhibits a similar ecosystem to the other: there are always tyrannosaurs, horned dinosaurs (ceratopsians), duck-billed dinosaurs (hadrosaurs), and raptors (dromaeosaurs) among other creatures. However, there are always different species belonging to each group. Even formations of the same age, or nearly the same age, differ in their species when they occupy different latitudes on the continent. This suggests that there were multiple “mini-ecosystems” throughout Laramidia some seventy-five million years ago.

Around seventy million years ago, as continents shifted and climates grew colder, the sea began to dry up. This linked the mini-continents of Laramidia and Appalachia once again and opened vast new regions for land animals to inhabit. The fossils of this age suggest that the divided mini-ecosystems began to blend together. It was into this great new world that Tyrannosaurus rex appeared on the scene, occupying the role of top predator until the extinction of the dinosaurs sixty-five million years ago.

The divided continent of North America. Note that the column on the left displays only a small number of the dinosaurs in each ecosystems. Also note that the Kirtland Formation is slightly younger than the others displayed.

Earlier Burgess-Shale-Type Fossils Found in Greenland

Wednesday, January 31, 2018

Graham Budd has been critical of associations between Ediacaran fauna and Cambrian animals, and has also debunked alleged Precambrian animal ancestors such as Vernanimalcula (Stephen Meyer, Darwin’s Doubt, pp. 85, 90-91). Budd also was in attendance at the Darwin-doubting Altenberg 16 conference in 2008 (p. 292), confessing that the fossil record tells little about the origin of biological forms. This Cambrian expert from Uppsala University has a new paper in Geology describing new exquisitely-preserved fossils of the Burgess Shale type, but earlier. Along with lead writer Ben Slater, Graham Budd’s team unveils photographs of tiny but exquisite parts of arthropods, worms and other animals that burst into appearance in the Cambrian Explosion. What’s amazing is that these fossils were collected not in Canada or China, but in the northern reaches of Greenland.

The location, called Sirius Passet in Peary Land in the far north of Greenland, has been known as an early Cambrian fossil site, but it lies close to a geological fold belt. Having been heated to 200° C or more by metamorphism, most of the fossils at Sirius Passet have suffered thermal alteration and are difficult to interpret. Not far to the south, however, the team found sites in the same formation that escaped most of the alteration. News from Uppsala University describes how they found a “treasure trove of highly detailed fossils” of the Burgess Shale type.

The ‘Cambrian explosion’ of animal diversity beginning ~541 million years ago is a defining episode in the history of life. This was a time when the seas first teemed with animal life, and the first recognisably ‘modern’ ecosystems began to take shape.

Current accounts of this explosion in animal diversity rely heavily on records from fossilised shells and other hard parts, since these structures are the most likely to survive as fossils. However, since most marine animals are ‘soft-bodied’ this represents only a small fraction of the total diversity.

Rare sites of exceptional fossilisation, like the world-famous Burgess Shale, have revolutionised palaeontologists understanding of ‘soft-bodied’ Cambrian life. Because of the special conditions of fossilisation at these localities, organisms that did not produce hard mineralized shells or skeletons are also preserved. Such sites offer a rare glimpse into the true diversity of these ancient seas, which were filled with a dazzling array of soft and squishy predatory worms and arthropods (the group containing modern crustaceans and insects). [Emphasis added.]

Also important is that these fossils date earlier than the Burgess Shale by 10 million years (518 million instead of 508 million), and yet are recognizable as the same animals. This indicates that the Cambrian animals had a global distribution at the time they were fossilized. The same animals are found many thousands of miles apart on three continents.

Instead of the large, articulated fossils from China and Canada, those at the Greenland sites are made up of tiny fragments. So rich were the deposits, they often found 100 specimens in a 50-gram sample.

A team of palaeontologists from Uppsala (Ben Slater, Sebastian Willman, Graham Budd and John Peel) used a low-manipulation acid extraction procedure to dissolve some of these less intensively cooked mudrocks. To their astonishment, this simple preparation technique revealed a wealth of previously unknown microscopic animal fossils preserved in spectacular detail.

Most of the fossils were less than a millimetre long and had to be studied under the microscope. Fossils at the nearby Sirius Passet site typically preserve much larger animals, so the new finds fill an important gap in our knowledge of the small-scale animals that probably made up the majority of these ecosystems. Among the discoveries were the tiny spines and teeth of priapulid worms — small hook shaped structures that allowed these worms to efficiently burrow through the sediments and capture prey. Other finds included the tough outer cuticles and defensive spines of various arthropods, and perhaps most surprisingly, microscopic fragments of the oldest known pterobranch hemichordates — an obscure group of tube-dwelling filter feeders that are distant relatives of the vertebrates. This group became very diverse after the Cambrian Period and are among some of the most commonly found fossils in rocks from younger deposits, but were entirely unknown from the early Cambrian. This new source of fossils will also help palaeontologists to better understand the famously difficult to interpret fossils at the nearby Sirius Passet site, where the flattened animal fossils are usually complete, but missing crucial microscopic details.

The photos of the small carbonaceous fossils (SCFs) in the paper show exquisite details of identifiable Burgess Shale type animals. Pieces of trilobite cuticles were also found. Trilobites are among the most complex of Cambrian animals, possessing articulated limbs, eyes and multiple body systems for locomotion, digestion and survival. The authors seem most excited about finding the earliest pterobranch hemichordates (a type of filter feeder known in the Burgess Shale), recognizing that the worldwide distribution indicates an even earlier origin. The paper says,

Our report of early Cambrian pterobranch fragments confirms this hypothesis [of early origin], and their potential affinities to Graptolithina also suggest that the divergence and radiation of the pterobranch clades containing cephalodiscids and graptolites had a somewhat deeper, early Cambrian origin.

Nowhere do they suggest evidence for evolution or transitional forms. On the contrary, these new fossils confirm the picture of abrupt appearance and stasis. The best the team can say is that this fossil site offers “new insights” into the fossilization process and may “reshape our view” of this ‘episode’ known as the Cambrian explosion:

“The sheer abundance of these miniature animal fossils means that we have only begun to scratch the surface of this overlooked resource, but it is already clear that this discovery will help to reshape our view of the non-shelly animals that crawled and swam among the early Cambrian seas more than half a billion years ago,” says Sebastian Willman, researcher at the Department of Earth Sciences, Uppsala University.

Marshall Is Back

In 2013, U.C. Berkeley paleontologist Charles Marshall published a critique of Darwin’s Doubt in the journal Science that Stephen Meyer considered the first critical review to actually address the main argument in the book: the inability of standard evolutionary mechanisms to explain the origin of morphological novelty in the Cambrian period. Meyer wrote a four-chapter response to Marshall in the follow-up book, Debating Darwin’s Doubt (2015).

Late last year, Marshall wrote an article in Science (November 29, 2017) called “A tip of the hat to evolutionary change,” in which he reviewed another paper in the same issue that claims to reveal “an unexpectedly simple pattern of driver action in peak evolutionary success.” That paper by Žliobaitė et al concludes from the fossil record of herbivorous mammals that species rise toward success and decline toward extinction in a “hat shape” graph (thus his title).  In passing, Marshall admits that “one of the challenges of studying evolution … is the hierarchical structure of the evolutionary process.” What drives innovation: abiotic (environmental) processes or biotic processes, like competition? How do they work together? How simple is the rise to “evolutionary success”?

Though only peripherally related to evolutionary processes in the Cambrian explosion, Marshall’s article shows what he thinks these days about the origin of biological novelty. Old-fashioned Darwinian competition is a driver of extinction, he agrees, but what drives innovation?

The results of Žliobaitė and colleagues’ work also provide insight into the drivers of evolutionary innovation. The authors’ data for North America and Europe show that, although both biotic and abiotic factors contribute roughly equally to genus origination rates, neither contribution is statistically significant. As the authors note, this provides evidence that evolutionary innovation is not driven by biotic or abiotic external changes. Instead, the data support the idea that evolutionary innovation is influenced by intrinsic factors — the less-predictable origin of the ‘right’ variants at the right time, able to exploit either existing or new resources.

This statement indicates that nothing much has changed in his thinking. It appears Marshall still has no better tool for innovation than lucky mutations that just happen to arrive at the right time to be exploited. How this solution can possibly address the “hierarchical structure of the evolutionary process” leading to body plans with hierarchical levels of morphological innovation seems lost in academic jargon and generalizations.

The Greenland fossils are observational facts. Graham Budd’s team in that cold, remote, northern wasteland could look at those cold, hard facts under a microscope, seeing complexity that shouldn’t be there by any unguided natural process. If Charles Marshall had a better mechanism for innovation than sheer dumb luck, he has had years to announce it. Until and unless he does, Meyer’s thesis remains unchallenged: only intelligent design can account for the functional hierarchical organization revealed by the Cambrian animals.

Photo: Location in Greenland where fossils were found, by John S. Peel, via Uppsala University.

Source: Evolution News @DiscoveryCSC

Kootenayscolex barbarensis: Cambrian Period Worm Had Hair-Sized Bristles on Its Head and Body

Tuesday, January 30, 2018

Kootenayscolex barbarensis. Image credit: Danielle Dufault / Royal Ontario Museum.

 A new species of bristle worm that lived about 508 million years ago (Cambrian period) has been identified from fossils found in Marble Canyon and Burgess Shale sites, both in British Columbia, Canada.

Dubbed Kootenayscolex barbarensis, the ancient worm was a type of annelid, a highly diverse group of animals that includes modern-day leeches and earthworms.

“While the diversity of annelids in terms of their anatomies and lifestyles makes them ecologically important and an evolutionarily interesting group to study, it also makes it difficult to piece together what the ancestral annelid may have looked like,” said Karma Nanglu, a PhD candidate at the University of Toronto and a researcher at the Royal Ontario Museum.

Although annelids are found all over the world — from the bottoms of oceans and lakes to mountain glaciers — their early evolutionary history is confounded by a poor fossil record, with few species described from well-preserved body fossils near the evolutionary origins of the group.

“While isolated pieces of annelid jaws and some mineralized tubes secreted by the animals are well known, preservation of their soft tissues is exceedingly rare,” said Dr. Jean-Bernard Caron, also from the University of Toronto and the Royal Ontario Museum.

“You need to look to truly exceptional fossil deposits like those found in the Burgess Shale to find well-preserved body fossils. Even then, they’re quite uncommon and many of the currently described species there are still poorly understood.”

Kootenayscolex barbarensis had a pair of long sensory structures called palps on its head, with a small medial antenna between them. Its body was covered in fleshy appendages called parapodia which bear bristles called chaetae. These structures are used for movement. Image credit: Jean-Bernard Caron / Royal Ontario Museum.

Kootenayscolex barbarensis was up to 1.2 inches (3 cm) long and had hair-sized bristles on the head.

“The worm possessed paired bundles of hair-sized bristles spread along the body,” Nanglu said.

“This is one of the diagnostic features of this group of animals.”

“However, unlike any living forms, these bristles were also partially covering the head, more specifically surrounding the mouth.”

“The new species seems to suggest that the annelid head evolved from posterior body segments which had pair bundles of bristles, a hypothesis supported by the developmental biology of many modern annelid species.”

“The fine anatomical details preserved in Kootenayscolex barbarensis allow us to infer not only its evolutionary position, but also its lifestyle,” Nanglu added.

“Sediment preserved inside their guts suggests that, much as their relatives do in modern ecosystems, these worms served an important role in the food chain by recycling organic material from the sediment back to other animals that preyed on them.”

The findings are published in the January 22 edition of the journal Current Biology.


Karma Nanglu & Jean-Bernard Caron. 2018. A New Burgess Shale Polychaete and the Origin of the Annelid Head Revisited. Current Biology 28 (2): 319-326; doi: 10.1016/j.cub.2017.12.019

Source: www.sci-news.com

Oldest Fossil Ever Found in Utah Belonged to Coyote-like Dinosaur

Tuesday, January 23, 2018

The biggest discoveries can be made by the unlikeliest of scientists, like a volunteer sifting through desert rocks.

Paleontologists at Dinosaur Journey say that's exactly how the oldest known fossil found in Utah was unearthed.

We got a sneak peek at the hip bone of the dinosaur.

Rob Gay says a little more than 10 years ago, a group outing turned up the fossil that's more than 200 million years old. To put that into perspective, that means the fossil is from the very beginning of dinosaur time.

"And then we looked at this fossil, specifically and compared it to known dinosaurs from Europe, Asia, Africa, South America, and of course across the American West at this same time period. And we found it shares a lot of characteristics with a group of early predatory dinosaurs called Neotherapods," said Rob Gay, Paleontologist, Colorado Canyons Association.

When it was alive the dinosaur would have been about nine to 12 feet long and stood waist high at its head and had pointy teeth. Gay says it would have been like a prehistoric coyote.

The fossil isn't on display right now.

Source: www.kjct8.com

New Fossil Shows When Worms Developed Heads

Thursday, January 25, 2018

A fossil dating from the Cambrian, more than 500 million years ago. Note the bristles partially covering the head. Image credits: Jean-Bernard Caron/Royal Ontario Museum.

A new study based on recent findings might shed a new light on annelids (ringed worms). Researchers now have solid evidence that these animals developed heads more than 500 million years ago. An extremely well-preserved fossil also suggests how the head evolved in the first place.

We take some of our biological features — such as the head — for granted. But five hundred million years ago, things were much more unfamiliar. Not only was the planet a completely different place, with different landscapes and atmospheric conditions, but heads were a scarce commodity. It’s not clear exactly when creatures started to evolve heads — areas of the body with concentrated sensorial functions — but some of the earliest evidence we have comes from 500 million years ago, during a period called the Cambrian.

Now, paleontologists working in Canada have found an intriguing Cambrian fossil which sheds new light on how annelids developed heads.

The fossil was found in the 508-million-year-old Marble Canyon site in the Burgess Shale in British Columbia. Burgess Shale is one of the best places for Cambrian fossils, with a long list of intriguing finds that enables us to better understand how life evolved. Now, we can add a new entry to that list: Kootenayscolex.

“508 million years ago, the Marble Canyon would have been teeming with annelids,” said Karma Nanglu, a University of Toronto PhD candidate, and a researcher at the Royal Ontario Museum, as well as the study’s lead author. “The fine anatomical details preserved in Kootenayscolex allow us to infer not only its evolutionary position, but also its lifestyle. Sediment preserved inside their guts suggest that, much as their relatives do in modern ecosystems, these worms served an important role in the food chain by recycling organic material from the sediment back to other animals that preyed on them.”

Kootenayscolex barbarensis, as its full name goes, had paired bundles of hair-sized bristles spread along the body, which allows paleontologists to positively identify it as an annelid. But unlike any other discovered fossil, these bristles were partially covering the head — specifically, the mouth. This seems to support the theory that the head evolved from posterior body segments, something which was also suggested by research on modern species.

However, fossil evidence is extremely scarce. Since annelids are invertebrates (Kootenayscolex actually emerged as one of the first annelids), preservation of their soft bodies is extremely rare. The very process of fossilization favors the preservation of bones and other hard body parts, which makes this finding even more valuable: not only is it a rare occurrence of a preserved soft body, but it’s also caught in an important moment of its evolutionary history.

With over 17,000 extant species including ragworms, earthworms, and leeches, annelids are one of the most diverse groups on Earth. They can thrive in a variety of environments, from marine environments as distinct as tidal zones and hydrothermal vents to freshwater lakes and moist terrestrial environments. Wherever there’s some form of humidity, there’s a good chance to find an annelid. This diversity makes them an extremely interesting and important group to study, but it also makes it extremely difficult to look at the broad picture.

“Annelids are a hugely diverse group of animals in both their anatomies and lifestyles,” added Nanglu. “While this diversity makes them ecologically important and an evolutionarily interesting group to study, it also makes it difficult to piece together what the ancestral annelid may have looked like.”

The team’s research is due to be published in the journal Current Biology.

Source: www.zmescience.com