Cockroach ancient geographic and genomic history traced back to last supercontinent

More than 100 species of cockroaches were used in the new genomic study.

Cockroaches are so hardy, a popular joke goes, that they've occupied the Earth long before humans first appeared -- and will probably even outlast us long after we have annihilated each other by nuclear war.

But now, researchers have used the latest in genomic data to gain the most detailed information yet of their evolutionary history.

Armed with a vast amount of genomic information, a team of researchers led by Dr. Thomas Bourguignon, now professor at the Okinawa Institute of Science and Technology, has performed the first molecular dating to gain the clearest picture yet of the biogeographical history of cockroaches.

They have traced back the key evolutionary time points of the cockroach -- all the way back almost 300 million years ago when the Earth's mass was organized into the Pangaea supercontinent.

This fossil record of cockroaches suggests that most extant families evolved during the breakup of Pangaea (which began ~200 Ma) and prior to the beginning of continental separation within Gondwana (~135 Ma).

"Our results indicate that extant cockroach families have evolved over periods of up to ~180 million years," said Bourguignon. "Through reconstructions of the ancestral distribution of cockroaches using the known distributions of extant genera sampled in this study, we found evidence that continental breakup has had important impacts on cockroach biogeography."

To do so, they estimated divergence times of all living cockroach families, based on the complete mitochondrial genomes of 119 cockroach species (and to help their molecular dating, compared with 13 termites, seven mantis and multiple other outgroups).

Their estimates indicate that the last common ancestor for cockroaches appeared much earlier than fossil evidence, around 235 million years ago. This was about 95 million years before the appearance of the first fossils attributed to modern cockroaches during the Cretaceous period around 140 million years ago, and before Pangaea broke up.

Since cockroaches can't fly very far, and for the most part would be terrestrially bound, one of the more appealing aspects of the study was to compare the cockroach divergence time with the geological history of the Earth.

The authors speculate that, like riding a raft, cockroaches spread to every part of the globe through the seismic continental drifts that occurred during the transition from Pangaea. This is illustrated by many sister cockroach lineages, which diverged prior Gondwana breakup, and diversified on their respective continental plates. But, in addition, within younger cockroach lineages, they did find evidence of transoceanic dispersal in regions near Australia and Indo-Malaysia.

"We believe that our results point to an important role for vicariance (continental drift) in determining the global distributions of cockroaches," said Bourguignon. "On a global scale, the fossil record also agrees with our hypothesis."

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3-D vision discovered in praying mantis

Praying mantis

Miniature glasses have revealed a new form of 3D vision in praying mantises that could lead to simpler visual processing for robots.

Publishing their latest research in Current Biology, the team at Newcastle University, UK has discovered that mantis 3D vision works differently from all previously known forms of biological 3D vision.

3D or stereo vision helps us work out the distances to the things we see. Each of our eyes sees a slightly different view of the world. Our brains merge these two views to create a single image, while using the differences between the two views to work out how far away things are.

But humans are not the only animals that have stereo vision. Other animals include monkeys, cats, horses, owls and toads, but the only insect known to have stereo vision is the praying mantis.

Going bug-eyed?

A team at the Institute of Neuroscience at Newcastle University funded by the Leverhulme Trust have been investigating whether praying mantis 3D vision works in the same way as humans'.

To investigate this they created special insect 3D glasses which were temporarily glued on with beeswax.

In their insect 3D cinema, they could show the mantis a movie of tasty prey, apparently hovering right in front of the mantis. The illusion is so good the mantises try to catch it.

The scientists could now show the mantises not only simple movies of bugs, but the complex dot-patterns used to investigate human 3D vision. This enabled them to compare human and insect 3D vision for the first time.

Humans are incredibly good at seeing 3D in still images. We do this by matching up the details of the picture seen in each eye. But mantises only attack moving prey so their 3D doesn't need to work in still images. The team found mantises don't bother about the details of the picture but just look for places where the picture is changing.

This makes mantis 3D vision very robust. Even if the scientists made the two eyes' images completely different, mantises can still match up the places where things are changing. They did so even when humans couldn't.

"This is a completely new form of 3D vision as it is based on change over time instead of static images," said behavioural ecologist, Dr Vivek Nityananda at Newcastle University. "In mantises it is probably designed to answer the question 'is there prey at the right distance for me to catch?'"

As part of the wider research, a Newcastle University engineering student developed an electronic mantis arm which mimics the distinct striking action of the insect.

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A one-two punch may have helped deck the dinosaurs

Colored and black points mark the global distribution of mid-ocean ridges, with ages of 66 million years ago created at spreading rates above and below 35 millimeters a year, respectively. Colors indicate the maximum gravity anomaly within 2 degrees.

The debate goes on: What killed off the dinosaurs?

New University of Oregon research has identified gravity-related fluctuations dating to 66 million years ago along deep ocean ridges that point to a "one-two punch" from the big meteor that struck off Mexico's Yucatan peninsula, possibly triggering a worldwide release of volcanic magma that could have helped seal the dinosaurs' fate.

"We found evidence for a previously unknown period of globally heighted volcanic activity during the mass-extinction event," said former UO doctoral student Joseph Byrnes.

The study by Byrnes and Leif Karlstrom, a professor in the UO's Department of Earth Sciences, was published Feb. 7 in Science Advances. It details a record of volcanism preserved along the mid-ocean ridges, which mark the oceanic boundaries of tectonic plates. The evidence comes from changes in the strength of gravity above the seafloor.

The findings of the UO's National Science Foundation-supported study, Karlstrom said, point to a pulse of accelerated worldwide volcanic activity that includes enhanced eruptions at India's Deccan Traps after the Chicxulub impact. The Deccan Traps, in west-central India, formed during a period of massive eruptions that poured out layers of molten rock thousands of feet deep, creating one of the largest volcanic features on Earth.

The Deccan Traps region has been in and out of the dinosaur debate. Rare volcanic events at such a scale are known to cause catastrophic disturbances to Earth's climate, and, when they occur, they are often linked to mass extinctions. Huge volcanic events can eject so much ash and gas into the atmosphere that few plants survive, disrupting the food chain and causing animals to go extinct.

Since evidence of the meteor strike near present-day Chicxulub, Mexico, surfaced in the 1980s, scientists have debated whether the meteor or the Deccan Traps eruptions drove the extinction event that killed off all nonavian dinosaurs.

Progressively improving dating methods indicate that the Deccan Traps volcanoes already were active when the meteor struck. Resulting seismic waves moving through the planet from the meteor strike, Karlstrom said, probably fueled an acceleration of those eruptions.

"Our work suggests a connection between these exceedingly rare and catastrophic events, distributed over the entire planet," Karlstrom said. "The meteorite's impact may have influenced volcanic eruptions that were already going on, making for a one-two punch."

That idea gained strength in 2015 when researchers at the University of California, Berkeley, proposed that the two events might be connected. That team, which included Karlstrom, suggested that the meteorite may have modulated distant volcanism by generating powerful seismic waves that produced shaking worldwide.

Similar to the impacts that normal tectonic earthquakes sometimes have on wells and streams, Karlstrom said, the study proposed that seismic shaking liberated magma stored in the mantle beneath the Deccan Traps and caused the largest eruptions there.

The new findings at the UO extend this eruption-triggering in India to ocean basins worldwide.

Byrnes, now a postdoctoral researcher at the University of Minnesota, analyzed publicly available global data sets on free-air gravity, ocean floor topography and tectonic spreading rates.

In his analyses, he divided the seafloor into 1-million-year-old groupings, constructing a record back to 100 million years ago. At about 66 million years, he found evidence for a "short-lived pulse of marine magmatism" along ancient ocean ridges. This pulse is suggested by a spike in the rate of the occurrence of free-air gravity anomalies seen in the data set.

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Rocky or gassy? Massive, dense super-Earth planet detected

An artist's impression of a stellar system with three super-Earths.

A star about 100 light years away in the Pisces constellation, GJ 9827, hosts what may be one of the most massive and dense super-Earth planets detected to date, according to new research led by Carnegie's Johanna Teske. This new information provides evidence to help astronomers better understand the process by which such planets form.

The GJ 9827 star actually hosts a trio of planets, discovered by NASA's exoplanet-hunting Kepler/K2 mission, and all three are slightly larger than Earth. This is the size that the Kepler mission determined to be most common in the galaxy with periods between a few and several-hundred-days.

Intriguingly, no planets of this size exist in our Solar System. This makes scientists curious about the conditions under which they form and evolve.

One important key to understanding a planet's history is to determine its composition. Are these super-Earths rocky like our own planet? Or do they have solid cores surrounded by large, gassy atmospheres?

To try to understand what an exoplanet is made of, scientists need to measure both its mass and its radius, which allows them to determine its bulk density.

When quantifying planets in this way, astronomers have noticed a trend. It turns out that planets with radii greater than about 1.7 times that of Earth are have a gassy envelope, like Neptune, and those with radii smaller than this are rocky, like our home planet.

Some researchers have proposed that this difference is caused by photoevaporation, which strips planets of their surrounding envelope of so-called volatiles -- substances like water and carbon dioxide that have low boiling points -- creating smaller-radius planets. But more information is needed to truly test this theory.

This is why GJ 9827's three planets are special -- with radii of 1.64 (planet b), 1.29 (planet c) and 2.08 (planet d), they span this dividing line between super-Earth (rocky) and sub-Neptune (somewhat gassy) planets.

Luckily, teams of Carnegie scientists including co-authors Steve Shectman, Sharon Wang, Paul Butler, Jeff Crane, and Ian Thompson, have been monitoring GJ 9827 with their Planet Finding Spectrograph (PFS), so they were able to constrain the masses of the three planets with data in hand, rather than having to scramble to get many new observations of GJ 9827.

"Usually, if a transiting planet is detected, it takes months if not a year or more to gather enough observations to measure its mass," Teske explained. "Because GJ 9827 is a bright star, we happened to have it in the catalog of stars that Carnegie astronomers been monitoring for planets since 2010. This was unique to PFS."

The spectrograph was developed by Carnegie scientists and mounted on the Magellan Clay Telescopes at Carnegie's Las Campanas Observatory.

The PFS observations indicate that planet b is roughly eight times the mass of Earth, which would make it one of the most-massive and dense super-Earths yet discovered. The masses for planet c and planet d are estimated to be about two and a half and four times that of Earth respectively, although the uncertainty in these two determinations is very high.

This information suggests that planet d has a significant volatile envelope, and leaves open the question of whether planet c has a volatile envelope or not. But the better constraint on the mass of planet b suggests that that it is roughly 50 percent iron.

"More observations are needed to pin down the compositions of these three planets," Wang said. "But they do seem like some of the best candidates to test our ideas about how super-Earths form and evolve, potentially using NASA's upcoming James Webb Space Telescope."

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Lab-grown eggs could pave way towards new fertility treatments

Magnification of a lab-grown, fully matured human egg ready for fertilisation.

Human eggs have been fully grown in a laboratory, in a move that could lead to improved fertility treatments.

Scientists have grown egg cells, which were removed from ovary tissue at their earliest stage of development, to the point at which they are ready to be fertilised.

The advance could safeguard the fertility of girls with cancer ahead of potentially harmful medical treatment, such as chemotherapy. Immature eggs recovered from patients' ovarian tissue could be matured in the lab and stored for later fertilisation.

Conventionally, cancer patients can have a piece of ovary removed before treatment, but reimplanting this tissue can risk reintroducing cancer.

The study has also given insight into how human eggs develop at various stages, which could aid research into other infertility treatments and regenerative medicine.

Scientists and medical experts worked together to develop suitable substances in which eggs could be grown -- known as culture mediums -- to support each stage of cell development. Their findings, using tissue donated by women who were undergoing routine surgery, build on 30 years of research.

In previous studies, scientists had developed mouse eggs to produce live offspring, and had matured human eggs from a relatively late stage of development. The latest study is the first time a human egg has been developed in the lab from its earliest stage to full maturity.

The study, carried out in collaboration with the Royal Infirmary Edinburgh, The Center for Human Reproduction in New York and the Royal Hospital for Sick Children in Edinburgh, was supported by the Medical Research Council. It was published in Molecular Human Reproduction.

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Neanderthals' lack of drawing ability may relate to hunting techniques

Neanderthals used thrusting spears to bring down tamer prey in Eurasia, while Homo sapiens, or modern humans, spent hundreds of thousands of years spear-hunting wary and dangerous game on the open grasslands of Africa.

Visual imagery used in drawing regulates arm movements in manner similar to how hunters visualize the arc of a spear. Neanderthals had large brains and made complex tools but never demonstrated the ability to draw recognizable images, unlike early modern humans who created vivid renderings of animals and other figures on rocks and cave walls. That artistic gap may be due to differences in the way they hunted, suggests a University of California, Davis, expert on predator-prey relations and their impacts on the evolution of behavior.

Neanderthals used thrusting spears to bring down tamer prey in Eurasia, while Homo sapiens, or modern humans, spent hundreds of thousands of years spear-hunting wary and dangerous game on the open grasslands of Africa.

Richard Coss, a professor emeritus of psychology, says the hand-eye coordination involved in both hunting with throwing spears and drawing representational art could be one factor explaining why modern humans became smarter than Neanderthals.

In an article recently published in the journal Evolutionary Studies in Imaginative Culture, Coss examines archaeological evidence, genomics, neuroscience studies, animal behavior and prehistoric cave art.

New theory of evolution

From this, he proposes a new theory for the evolution of the human brain: Homo sapiens developed rounder skulls and grew bigger parietal cortexes -- the region of the brain that integrates visual imagery and motor coordination -- because of an evolutionary arms race with increasingly wary prey.

Early humans hunted with throwing spears in sub-Saharan Africa for more than 500,000 years -- leading their increasingly watchful prey to develop better flight or fight survival strategies, Coss said.

Some anthropologists have suggested that throwing spears from a safe distance made hunting large game less dangerous, he said. But until now, "No explanation has been given for why large animals, such as hippos and Cape buffalo, are so dangerous to humans," he said. "Other nonthreatening species foraging near these animals do not trigger alert or aggressive behavior like humans do."

Drawn from earlier research on zebras

Coss' paper grew out of a 2015 study in which he and a former graduate student reported that zebras living near human settlements could not be approached as closely before fleeing as wild horses when they saw a human approaching on foot -- staying just outside the effective range of poisoned arrows used by African hunters for at least 24,000 years.

Neanderthals, whose ancestors left Africa for Eurasia before modern human ancestors, used thrusting spears at close range to kill horses, reindeer, bison, and other large game that had not developed an innate wariness of humans, he said.

Hunting relates to drawing

"Neanderthals could mentally visualize previously seen animals from working memory, but they were unable to translate those mental images effectively into the coordinated hand-movement patterns required for drawing," Coss writes.

Coss, who taught drawing classes early in his academic career and whose previous research focused on art and human evolution, used photos and film to study the strokes of charcoal drawings and engravings of animals made by human artists 28,000 to 32,000 years ago in the Chauvet-Pont-d'Arc Cave in southern France.

The visual imagery employed in drawing regulates arm movements in a manner similar to how hunters visualize the arc their spears must make to hit their animal targets, he concludes.

These drawings could have acted as teaching tools. "Since the act of drawing enhances observational skills, perhaps these drawings were useful for conceptualizing hunts, evaluating game attentiveness, selecting vulnerable body areas as targets, and fostering group cohesiveness via spiritual ceremonies," he writes.

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The Secrets of Hummingbird Agility Revealed

The hummingbird Aglaeactis cupripennis, common name Shining Sunbeam

Hummingbirds are maneuverability specialists, so researchers studying the basic science underlying agility went to where there are a lot of these agile avians: sites in remote parts of the Peruvian Amazon, Costa Rica, and the Ecuadorian Andes.

"Our first field site was at a biological reserve deep in the Peruvian Amazon, an area with many species of hummingbirds, but only accessible by boat," researcher Paolo Segre told Seeker.

"We ran our computers and cameras using solar panels and generators in a thatched hut with strategically placed rain buckets," added Segre, who was formerly with the University of British Columbia, but is now at Stanford University. "It was fun, but exhausting, and we had to deal with venomous snakes, curious monkeys, less-than-ideal conditions for our electronics, and a tricky geopolitical situation due to an illegal gold rush."

The challenging work paid off, however, as Segre and his team determined that evolved differences in muscle power and wing size govern agility in flight. The findings, published in the journal Science, have implications for everything from airplane design to therapies for people suffering from motor-sensory disorders. The latter is because the scientists developed a new way to quantify complex behaviors, be they birds zipping toward a feeder or a person talking.

Los Amigos Biological Station in Peru, one of the sites where researchers analyzed the agility of hummingbirds

For the study, Segre and his team managed to capture over 200 individual hummingbirds from 25 different species at the various sites using fine mesh mist-nets. Once captured, each bird was placed in a contained space and allowed to move freely. As the hummingbirds zipped around, the researchers filmed them and employed a tracking system, recording over 330,000 maneuvers in total.

The movements were analyzed with precision utilizing computer vision technology developed by co-author Andrew Straw at the University of Freiburg in Germany. The method was so precise that the scientists could even identify each particular hummingbird species just by observing its maneuvering patterns alone. Once studied, each bird was released back into the wild.

And, as Segre said, the conditions made this technical work difficult.

"One of the challenges of this study was miniaturizing the tracking system and optimizing it for travel and tropical conditions," he said. "Once we finally got it working, we still had to deal with some interesting situations.

"At one point," he continued, "our improvised lab in Peru was swarmed by army ants. This is a colony of voracious, biting, and stinging ants that form a wide carpet and attack anything in their path. At that point we had to shut the system down, leave the room, and wait for two days for the ants to move on."

With the ants and other obstacles out of the way, the scientists were very surprised to see that the heftiest hummingbirds outmaneuvered all of the other birds.

"That's because previous studies of bats, birds, and other animals have shown that within a species, increases in body mass can have a detrimental effect on many aspects of flight," co-lead author Roslyn Dakin of the University of British Columbia department of zoology told Seeker.

"Our results explain why larger hummingbird species can outmaneuver smaller ones," she continued. "It's because of the correlated evolution of other traits that can compensate for their increased body mass."

These other traits largely concern their wings and muscles. Muscle capacity, or the ability to quickly lift maximum weight, was important for fast acceleration maneuvers. Fast rotations and sharp turns, on the other hand, relied more upon wing loading, which is the ratio of body mass to wing area.

"Thus, a bird can have lower wing loading either by having larger wings or lower body mass," senior author Douglas Altshuler, also from the University of British Columbia, told Seeker.

The multi-camera hummingbird tracking system

Another unexpected finding was that high and low elevation hummingbirds perform similarly. In a previous study, Dakin and her colleagues took a predominantly low-elevation species, the Anna's hummingbird, and moved it to a high elevation. They found that the transplanted birds were not able to accelerate, de-accelerate, or to turn as quickly because of the altitude.

For the new study, they tested species that naturally live at high and low elevations — "on their home field, so to speak," she said.

The high-elevation species in this case were, by most measures, just as agile as the low-elevation birds, suggesting that they can compensate for the effects of altitude on some aspects of maneuvering flight.

"The exception was the complex turns," she said. "Low-elevation species will turn on a dime more often, suggesting that there is at least one constraint of altitude that high-elevation species haven't overcome."

A unique aspect of the study — aside from the remarkable number of studied hummingbirds — is that it employed a geometrical framework to extract individual features from complex movements, which in this case included different types of rotations, turns, and "translations."

Dakin explained that translations included maneuvers when the birds accelerated or de-accelerated their forward speed while maintaining a fairly consistent altitude.

The observed rotations and turns were equally impressive. Some hummingbirds, for example, executed pitch-roll turns. For these moves, the birds would slow down, raise their body orientation toward vertical, rotate, and then accelerate again in a new direction.

"They use their agility for mating displays, competition, catching prey, and escaping predators," Altshuler said. "Some of these behaviors are important for small animals, and some of this is probably a by-product of their hovering ability."

Heliodoxa aurescens, commonly known as Gould's Jewelfront

As admirers of hummingbirds know, the birds appear to be incredibly intelligent and social creatures. The researchers, however, did not examine how brain power affects agility.

"Remember that some of the most maneuverable flyers are small insects, such as fruit flies," Altshuler said.

The scientists focused their work on hummingbirds because of these avians' feats of flight. As Altshuler told Seeker, "It is often effective to study organisms that are extremely good at doing something to gain novel insight into how that feature works."

The researchers believe their definition of maneuverability as a combination of translations, rotations, and complex turns is a framework that may apply to all mobile animals, and not just to those that accomplish such moves in midair.

The authors suspect that muscle capacity could explain variation in translational maneuvers in other animals, including humans. In terms of just flying animals, the researchers now theorize that wing load explains the variation seen in rotational maneuvers. They hope to test this and other possibilities in the future.

Read more at Seeker

Walking fish suggests locomotion control evolved much earlier than thought

Little skate embryos, mid-gestation.

Cartoons that illustrate evolution depict early vertebrates generating primordial limbs as they move onto land for the first time. But new findings indicate that some of these first ambulatory creatures may have stayed under water, spawning descendants that today exhibit walking behavior on the ocean floor. The results appear February 8 in the journal Cell.

"It has generally been thought that the ability to walk is something that evolved as vertebrates transitioned from sea to land," says senior author Jeremy Dasen, a developmental neurobiologist in the Department of Neuroscience and Physiology at the New York University School of Medicine. "We were surprised to learn that certain species of fish also can walk. In addition, they use a neural and genetic developmental program that is almost identical to the one used by higher vertebrates, including humans."

The researchers focused on the neural development of a type of fish called the little skate (Leucoraja erinacea). Related to sharks and rays, these cartilaginous fish are considered to be among the most primitive vertebrates, having changed little from their ancestors that lived hundreds of millions of years ago.

Little skates have two sets of fins: large pectoral fins, which they use for swimming, and smaller pelvic fins, which they use for walking along the ocean floor. Previous research had shown that these fish use alternating, left-right motions when they walk, similar to the motions used by animals that walk on land, making them a valuable model to study.

The investigators used a technology called RNA sequencing (RNA-seq) to assess the repertoire of genes that are expressed in the skate's motor neurons. They found that many of these genes are conserved between skates and mammals. In addition, they discovered that the neuronal subtypes that are essential for controlling the muscles that regulate the bending and straightening of limbs are present in the motor neurons of the skate. "These findings suggest [that] the genetic program that determines the ability of the nerves in the spinal cord to articulate muscles actually originated millions of years earlier than we have assumed they appeared," Dasen says. "This fin-based movement and walking movements use the same developmental program."

The discovery went beyond the nerves that control muscles. The researchers also looked at a higher level of circuitry -- the interneurons, which connect to motor neurons and tell them to activate the muscles. Interneurons assemble into circuits called central pattern generators (CPGs). CPGs determine the sequence in which different muscles are activated, thereby controlling locomotion. "We found that the interneurons, nearly a dozen types, are also highly conserved between skates and land mammals," Dasen says.

Read more at Science Daily

A Method for Studying Dinosaurs Can Also Help Fight the Spread of the Flu

Non-avian dinosaurs and flu viruses would appear to share few, if any, characteristics. After all, one group consisted of large animals that went extinct millions of years ago, while the other includes pathogenic particles that are unfortunately still very much with us.

The evolutionary histories of dinosaurs and viruses have more in common than one might expect. And a new method for studying the animals is already being recruited in the fight against influenza and additional viruses that can infect humans and other species. The groundbreaking technique is described in the journal Nature Ecology & Evolution.

The breakthrough involves projecting shifting rates of evolutionary change onto the surface of a sphere, instead of on a flat plane. This allows biogeographical data to be analyzed within an Earth-resembling model that captures speed, direction, and distance moved over short to long periods of time.

"As long as a group of organisms can be placed in a phylogenetic tree, which describes how species are related to each other, or a single species of interest can be placed in the context of its close relationships within a phylogenetic tree, and has geographical data — longitudes and latitudes of where the organisms have occurred on the Earth — the method we develop can reconstruct where the organisms’ ancestors existed on the globe," co-author Andrew Meade of the University of Reading told Seeker.

On the dinosaur side of the research, the technique has already revealed new insights concerning the origin and dispersal of dinosaurs.

Meade, lead author Ciara O'Donovan, and senior author Chris Venditti plugged extensive information on dinosaurs and their fossil record into their model. The data came from the Paleobiology Database, an online resource curated by numerous scientists around the world.

The information shows that dinosaurs first evolved in what is now South America at close to the beginning of the Mesozoic Era, which lasted in its entirety from about 252–66 million years ago.

"Prior to the dinosaurs’ origination there was an extreme extinction event," O'Donovan told Seeker. "This happened 252 million years ago, at the Permian-Triassic boundary and is the largest extinction event to have occurred in Earth’s history."

"This decimated the majority of life on Earth and therefore may well have provided the dinosaurs with a blank canvas to colonize," she added. "This fairly ‘empty Earth’ would have been totally open and up for grabs, and the dinosaurs were able to spread across the globe quickly, taking every ecological opportunity in their path."

Pangea — the single, giant landmass that later broke up to form the continents — was additionally whole when the dinosaurs originated about 231 million years ago. This meant that there were few, if any, geographical barriers preventing the dinosaurs' movement.

O'Donovan and her team suspect that the dinosaurs must have had some beneficial biological predisposition, enabling them to take advantage of the "blank canvas" they found themselves on. This aided their moving, dispersing, and colonizing new habitats. The remains of dinosaurs have remarkably been found on every continent, from what are now the polar regions to nearly every place in between.

The researchers tracked the movements through evolutionary time of the four major groups of dinosaurs — Ornithischians, Sauropods, Theropods, and birds — as well as certain individual species, like Tyrannosaurus rex.

Six reconstructed evolutionary paths for the dinosaur species a) Rhoetosaurus brownei, b) Archaeopteryx lithographica, c) Stegosaurus stenops, d) Andesaurus delgadoi, e) Dromaeosaurus albertensis, f) Tyrannosaurus rex.

At the start of their research, the scientists thought that each of the four dinosaur groups would exhibit different dispersal patterns. They especially thought that would be the case for birds.

The researchers determined, however, that all of the animals shared a rapid initial expansion whereby the dinosaurs speciated quickly and moved over great distances. This was followed by a continual and gradual slow-down as the animals approached the critical Cretaceous-Tertiary boundary 66 million years ago.

Venditti explained: "As time went on, dinosaurs both moved less, and fewer new species were produced. The less they could move, the more likely it would have been that any speciation that did occur would be by specialization in the environment the dinosaurs were already living in."

"The idea that the dinosaurs were running out of space fits here," he continued. "The lack of space explains why the dinosaurs were less able to speciate to replace species that were going extinct. And species may have been going extinct owing to becoming specialized and therefore being vulnerable to changes within the environment."

The new information supports the conclusions of a prior University of Reading study that was published in 2016 in the journal Proceedings of the National Academy of Sciences. It found that 50 million years before the asteroid impact that occurred in the Yucatan peninsula 66 million years ago, dinosaurs were already in decline.

Nevertheless, the ancestors of today's birds survived.

"Where avian ancestors were not able to move to new environments owing to the lack of space by that time, they specialized to take advantage of a type of space previously unoccupied by dinosaurs — aerial space," O'Donovan said. "They were able to do this because they had feathered wings. In doing this, they would have been able to explore ecological opportunities that were previously inaccessible and would have been able to evade competition with their relatives on the ground."

It is possible that birds benefitted from the die-off in the same way that non-avian dinosaurs did after the Permian-Triassic extinction event.

Fossil of Archaeopteryx lithographica, excavated in southern Germany

The researchers suspect that birds might have changed their movements to take advantage of the ecosystem voids. The ancestors of mammals are thought to have done the same. The new model created for the study only goes up to 66 million years ago, however, so the geographical signatures for birds and mammals since then have not been determined yet.

The model can be applied to anything for which a certain amount of ancestral history is known. On a small scale, and considering the current popular technologies related to DNA, it could reveal the geographical signature of an individual family over time.

Meade said that the technique could also "be useful in the case of viruses, or perhaps plants linked to agriculture or invasive species if we wish to know where a certain virus originated, or how quickly a plant has spread or a species has invaded non-native environments."

The model could also show far more than the history of one particular human family.

"It is also possible to represent human cultures in a phylogenetic tree by using similarities and differences in language," Meade explained. "This means it would be possible to study the expansion of humans across the planet using our approach."

Read more at Seeker

Cancer ‘Vaccine’ Activates Immune System Against Tumors

Scientists devised a pinpointed immunotherapy regimen that eradicated tumors throughout the body in mice.

The human immune system is armed with specialized white blood cells — T cells, B cells, natural killer cells, and more — that target and kill invading viruses, bacteria, and other pathogens. Cancer cells, however, use signaling tricks to suppress the body’s natural immune response, sidelining T cells while a tumor grows unchecked.

For decades, scientists have been chasing a cancer “vaccine” that wakes the sleeping army of immune cells and trains it to attack cancer. Now a new technique has scientists injecting microdoses of immune-boosting agents directly into cancerous tumors, which appears to not only kill the targeted tumor, but eradicate similar tumors elsewhere in the body — at least in mice.

In a preclinical study published in Science Translational Medicine, 90 mice with multiple transplanted tumors were injected with two immunotherapy agents, and in 87 cases, all signs of cancer were wiped out.

The promising results, reported by Ronald Levy at the Stanford University School of Medicine, provide further hope that immunotherapy is the future of cancer treatment. Instead of bombarding the body with high doses of toxic chemicals and radiation, we can recruit our own immune systems to fight back.

In Levy’s two-step cancer vaccine, a short stretch of DNA called a CpG oligonucleotide was first injected into the tumor site. CpG is something called a Toll-like receptor, a special kind of immune system protein that recognizes invading pathogens.

When micrograms of this protein (millionths of a gram) were injected into the mouse tumors, they activated the expression of a receptor called OX40 on nearby T cells that had originally swarmed to the tumor site, but had been rendered inactive.

The second injection contained an antibody that attached to those newly activated OX40 receptors and essentially turned the T cells back “on.” Before their activity was suppressed, those same T cells were primed to respond to the precise antigens produced by the tumor. With a boost from the vaccine, now they were back in action.

The mice in the Stanford experiment were transplanted with lymphoma tumors, but Levy said in a statement that the vaccine achieved similar results with breast, colon, and melanoma tumors. Even more impressive was that some of the reactivated T cells circulated throughout the body and attacked tumors far from the injection site.

“When we use these two agents together, we see the elimination of tumors all over the body,” said Levy. “This approach bypasses the need to identify tumor-specific immune targets and doesn’t require wholesale activation of the immune system or customization of a patient’s immune cells.”

Levy was referring to other emerging immunotherapy cancer treatments like CAR-T therapy, in which a patient’s T cells are removed and genetically altered to carry custom-made antigen receptors for the patient’s particular type of cancer. And checkpoint inhibitors, a therapy that targets specific immune system proteins that allow cancer cells to hide in plain sight.

Another promising immunotherapy uses the listeria bacteria as a vector to deliver tumor-specific antigens to the entire immune system.

The listeria technique was developed by Yvonne Paterson at the University of Pennsylvania School of Medicine and has been licensed by Advaxis Immunotherapies, which is already testing its vaccine formula in phase 3 human trials for certain types of late-stage cancers. The Stanford team just began recruiting its first 15 human patients.

Reached by email, Paterson called Levy’s paper “a very nice preclinical study that shows the power of expanding and activating pre-existing tumor-specific T cells that accumulate in tumors but are not able to control tumor growth.”

One disadvantage of the direct-injection technique, said Paterson, is that it’s limited to tumors that are easily accessible.

“One can see how his approach might work in the human equivalents of lymphoma, breast cancer and also in melanoma, where there is surface accessible tumor,” add Paterson. “However, there are many cancers to which it might not be very applicable.”

Levy is a pioneer in the immunotherapy field, winning FDA approval in 1997 for the first lab-designed antibody to be used in conjunction with traditional chemotherapy. But Levy is not the first to experiment with immune-boosting vaccines that target T cells closest to the tumor site.

Read more at Seeker

This Is the Most Detailed Simulation of the Universe

Visualization of the intensity of shock waves in the cosmic gas (blue) around collapsed dark matter structures (orange/white). Similar to a sonic boom, the gas in these shock waves is accelerated with a jolt when impacting on the cosmic filaments and galaxies.

What would you do if you had access to one of the most powerful high-performance computing systems in the world? A group of astrophysicists have used the Hazel Hen machine, Germany's fastest mainframe computer, to create the most detailed simulation ever of the entire universe from almost the beginning of time.

Called Illustris: The Next Generation, or IllustrisTNG, the simulation models a cube-shaped universe that is actually much smaller than our own. But it follows the formation of millions of galaxies in a representative region of a universe that is almost one billion light-years per side. The scale and detail of the simulation allows astronomers to study how galaxies form, evolve, and grow, as stars are born and live out their lives.

"When we observe galaxies using a telescope, we can only measure certain quantities," team member Shy Genel from the Flatiron Institute's Center for Computational Astrophysics said in a statement. "With the simulation, we can track all the properties for all these galaxies. And not just how the galaxy looks now, but its entire formation history."

Astronomers frequently use computer modeling to generate simulations of things like galaxy formation, dark matter, and stellar evolution. But the team says IllustrisTNG pushes these types of simulations to new limits — in size, resolution, and physical fidelity.

The new simulations are the “most information-packed, universe-scale simulation ever produced,” and it builds on the original Illustris simulation, which measured 350 million light years per side, according to the statement. For the new simulations, a team of astronomers from five institutions used more than 24,000 processors over more than two months and produced more than 500 terabytes of simulation data.

"Analyzing this huge mountain of data will keep us busy for years to come,” principal investigator Volker Springel at the Heidelberg Institute for Theoretical Studies said in the statement, “and it promises many exciting new insights into different astrophysical processes."

Other institutions involved were the Max Planck Institutes for Astronomy and Astrophysics, Harvard University, and the Massachusetts Institute of Technology. The team has produced three papers that have been published in the journal Monthly Notices of the Royal Astronomical Society.

Each simulation in IllustrisTNG evolves a large swath of a mock universe from soon after the Big Bang until the present day and takes into account a wide range of physical processes that drive galaxy formation. The simulations can be used to study a broad range of topics about how the universe — and the galaxies within it — evolved over time.

The astrophysicists involved say the new tool provides key insights into things like how black holes influence the distribution of dark matter, how heavy elements are produced and distributed throughout the cosmos, and where magnetic fields originate.

Springel said the simulations from IllustrisTNG demonstrate a high degree of realism, using “hydrodynamic simulations to produce predictions of how galaxies evolve” and how the so-called “cosmic web” — a network of filaments of dark matter that connect galaxies — changes over time and how they may change in the future.

Since the simulation can also look back in time, by mapping out the histories of these modeled galaxies, astronomers should be able to see what our own Milky Way looked like just as Earth was being formed.

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No volcanic winter in East Africa from ancient Toba eruption

Microscopic plant remains, called phytoliths, from grasses, sedges, palms, forbs, and trees that lived near Lake Malawi in East Africa about 74,000 years ago.

The massive Toba volcanic eruption on the island of Sumatra about 74,000 years ago did not cause a six-year-long "volcanic winter" in East Africa and thereby cause the human population in the region to plummet, according to new University of Arizona-led research.

The new findings disagree with the Toba catastrophe hypothesis, which says the eruption and its aftermath caused drastic, multi-year cooling and severe ecological disruption in East Africa.

"This is the first research that provides direct evidence for the effects of the Toba eruption on vegetation just before and just after the eruption," said lead author Chad L. Yost, a doctoral candidate in the UA Department of Geosciences. "The Toba eruption had no significant negative impact on vegetation growing in East Africa."

Researchers can use ancient plant parts that wash into and accumulate on the bottoms of lakes to reconstruct a region's past ecosystem. Yost and his colleagues studied microscopic bits of plants preserved in two sediment cores from Lake Malawi, which is approximately 570 kilometers (354 miles) long and is the southernmost of the East African Rift lakes.

Previous investigators found material from the Toba eruption in the Lake Malawi cores. That material pinpoints the time of the eruption and allowed Yost and colleagues to peer back in time 100 years before to 200 years after the Toba eruption. The team analyzed samples that represented, on average, every 8.5 years within that 300-year interval.

"It is surprising," Yost said. "You would have expected severe cooling based on the size of the Toba eruption -- yet that's not what we see."

Yost and his colleagues did not find marked changes in lower-elevation vegetation post-eruption. The team did find some die-off of mountain plants just after the eruption. Cooling from the eruption might have injured frost-intolerant plants, he said.

Had the region experienced the drastic, multi-year cooling post-Toba, the cores would have evidence of a massive die-off of the region's vegetation at all elevations, Yost said.

Part of the Toba catastrophe hypothesis suggests the eruption caused human populations to shrink.

"We know anatomically modern humans were living within 50 kilometers of Lake Malawi," Yost said. "People would have been able to travel to habitats and lower elevations that had little to no cooling effect from the Toba eruption."

Most of the region's known archaeological sites are from low elevations, not the mountains, he said.

Co-author Andrew S. Cohen, UA Distinguished Professor of Geosciences, said, "That a singular event in Earth history 75,000 years ago caused human populations in the cradle of humankind to drop is not a tenable idea."

The team's paper, "Subdecadal phytolith and charcoal records from Lake Malawi, East Africa imply minimal effects on human evolution from the ~74 ka Toba supereruption," is published online this week in the Journal of Human Evolution.

Yost's and Cohen's co-authors are Lily J. Jackson of the University of Texas at Austin, and Jeffery R. Stone of Indiana State University, Terre Haute. The National Science Foundation and the International Continental Scientific Drilling Program funded the research.

The Lake Malawi Drilling Project took the cores from the lake bottom in 2005, said Cohen, one of the principal investigators on the collaborative project. The lake is one of the deepest in the world. The material archived in the cores goes back more than one million years.

Plant and animal material washes into lakes and is deposited on the bottom in annual layers, so a sediment core contains a record of the past environments of a lake and of the surrounding land.

Yost studied two cores taken from the lake: one from the north end of the lake, which is closer to the mountains, and the other from the central part of the lake. Other researchers had pinpointed what layer in those cores had glass and crystals from the Toba eruption, Cohen said.

Yost took samples from the cores that straddled the eruption and analyzed the samples for charcoal and for silica-containing plant parts called phytoliths.

The work required hundreds of hours of peering through a microscope, said Yost, who is an expert in identifying the type of plant a particular phytolith came from.

If the Toba catastrophe hypothesis is true, the massive die-off of vegetation would have resulted in more wildfires and therefore more charcoal washing into the lake. However, he did not find an increase in charcoal outside the range of normal variability in the sediments deposited after the eruption.

Read more at Science Daily

Rainforest collapse 307 million years ago impacted the evolution of early land vertebrates

Rainforest

Researchers at the University of Birmingham have discovered that the mass extinction seen in plant species caused by the onset of a drier climate 307 million years ago led to extinctions of some groups of tetrapods, the first vertebrates to live on land, but allowed others to expand across the globe. This research is published today (7th February 2018) in the journal Proceedings of the Royal Society B.

The Carboniferous and Permian periods (358 -- 272 million years ago) were critical intervals in the evolution of life on land. During the Carboniferous Period North America and Europe lay in a single land mass at the equator which was covered by dense tropical rainforests. These rainforests flourished because of the warm humid climate, providing an ideal habitat for early tetrapods (vertebrates with four limbs), allowing them to diversify into a variety of species.

But towards the end of this period a major global environment change took place -- just as the number of tetrapod species began to increase, the rainforests started to disappear. The climate became much drier causing the mass extinction of many species within the dominant plant groups, such as horsetails and club mosses. Despite this being a catastrophic event for plants, it has been unclear how this affected the early tetrapod community.

Previous attempts to estimate the diversity changes during this period have been hindered by the fossil record, which has not been sampled equally in different time intervals or geographic areas. To fill these gaps in the data, the Birmingham researchers compiled a new dataset from the Paleobiology Database and used advanced statistical methods to estimate diversity and biogeographic changes.

The results of the study show that tetrapod diversity decreased after the rainforest collapse and the onset of drier conditions, largely due to the reduction in suitable habitats for amphibians which needed wet environments to survive.

However they also found that after the rainforest collapse surviving tetrapod species began to disperse more freely across the globe, colonising new habitats further from the equator. Many of these survivors were early amniotes, such as early reptiles, whose generally larger size relative to early amphibians allowed them to travel longer distances, and their ability to lay eggs meant they were not confined to watery habitats.

Emma Dunne, from the University of Birmingham's School of Geography, Earth and Environmental Sciences, said: 'This is the most comprehensive survey ever undertaken on early tetrapod evolution, and uses many newly developed techniques for estimating diversity patterns of species from fossil records, allowing us greater insights into how early tetrapods responded to the changes in their environment.'

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HINODE captures record-breaking solar magnetic field

Top: Visible light continuum image. Bottom: Magnetic field strength map. The color shows the field strength, from weak (cool colors) to strong (warm colors). Red indicates a location with a strength of more than 6,000 gauss (600 mT).

Astronomers at the National Astronomical Observatory of Japan (NAOJ) using the HINODE spacecraft observed the strongest magnetic field ever directly measured on the surface of the Sun. Analyzing data for 5 days around the appearance of this record breaking magnetic field, the astronomers determined that it was generated as a result of gas outflow from one sunspot pushing against another sunspot.

Magnetism plays a critical role in various solar phenomena such as flares, mass ejections, flux ropes, and coronal heating. Sunspots are areas of concentrated magnetic fields. A sunspot usually consists of a circular dark core (the umbra) with a vertical magnetic field and radially-elongated fine threads (the penumbra) with a horizontal field. The penumbra harbors an outward flow of gas along the horizontal threads. The darkness of the umbrae is generally correlated with the magnetic field strength. Hence, the strongest magnetic field in each sunspot is located in the umbra in most cases.

Joten Okamoto (NAOJ Fellow) and Takashi Sakurai (Professor Emeritus of NAOJ) were analyzing data taken by the Solar Optical Telescope onboard HINODE, when they noticed the signature of strongly magnetized iron atoms in a sunspot. Surprisingly the data indicated a magnetic field strength of 6,250 gauss. This is more than double the 3,000 gauss field found around most sunspots. Previously, magnetic fields this strong on the Sun had only been inferred indirectly. More surprisingly, the strongest field was not in the dark part of the umbra, as would be expected, but was actually located at a bright region between two umbrae.

HINODE continuously tracked the same sunspot with high spatial resolution for several days. This is impossible for ground-based telescopes because Earth's rotation causes the Sun to set and night to fall on the observatories. These continuous data showed that the strong field was always located at the boundary between the bright region and the umbra, and that the horizontal gas flows along the direction of the magnetic fields over the bright region turned down into the Sun when they reached the strong-field area. This indicates that the bright region with the strong field is a penumbra belonging to the southern umbra (S-pole). The horizontal gas flows from the southern umbra compressed the fields near the other umbra (N-pole) and enhanced the field strength to more than 6,000 gauss.

Read more at Science Daily

When Glaciers Retreated, Swings in Earth's Climate Subsided

A section of the Greenland ice sheet is seen from NASA's Operation IceBridge research aircraft along the Upper Baffin Bay coast on March 27, 2017 above Greenland.

The climate just doesn’t swing like it used to.

A pair of studies examining the prevailing temperatures found a marked decline in the long-term variability of Earth’s climate since the great glaciers retreated more than 20,000 years ago. Those swings, which took place over centuries, may have affected how and where humans were able to settle down — and might help improve our understanding of today’s climate changes.

One study, led by scientists at Germany’s Alfred Wegener Institute, concludes the shifting of climate patterns occurred far more often and diminished far more extensively in the area around Greenland than in the lower latitudes. The other, led by researchers at the University of Colorado, linked the decline of the North American ice sheet to changes in atmospheric circulation that caused changes all the way to Antarctica. Both studies were published February 5 in the research journal Nature.

Since the last ice age peaked about 21,000 years ago, average global temperatures have risen between 3 and 8 degrees Celsius (5.4 to 14.4 degrees Fahrenheit). The warming wasn’t always steady. It waxed and waned over hundreds, if not thousands, of years. To track those changes, Wegener paleoclimatologist Kira Rehfeld and her colleagues studied core samples taken from the Greenland ice sheet, which is nearly two miles thick in places.

Scientists compare the amount of a heavier oxygen isotope, oxygen-18, to the more common oxygen-16 in the ice to reconstruct temperatures. The more oxygen-18 is in the mix, the warmer the climate was at the time. They also looked at core samples from the sea floors across the world ocean, where fossil remains in the mud point to changes in ocean temperatures, and from inland lakes in Europe, Africa, China, and North America.

The three-and-a-half-year study found that the ice had largely retreated, the amount of variability in climate worldwide dropped to about a quarter of what it had been before.

“We see a reduction in temperature variability, that much is true,” Rehfeld told Seeker. “But we don’t see this huge decrease that everybody anticipated.”

Rehfeld compared the likely results of these variations to the effects of the Little Ice Age, a roughly 200-year cold snap that ended around 1800.

“In the Northern Hemisphere, glaciers advanced and villages had to move,” she said. “Basically, if you have more centennial to millennial variabilty, your glaciers would be constantly advancing and retreating so you would change where your village is every couple of hundred years.”

The decline was more pronounced in the higher latitudes, and particularly in Greenland, where variability has declined more than 70-fold. That would have made it more difficult for humans to settle down and form the communities that led to today’s civilization. But Rehfeld said similar oscillations don’t appear to have occurred as often in other places.

“In the tropics for example, there’s very little change,” Rehfeld said. “In the mid-latitudes, there’s a bit more, and the only the Greenland ice sheet appears to have really massive changes.”

She suggested a shrinking difference in temperatures between the high latitudes and the tropics over thousands of years may be why variability has gone down.

“The whole climate system depends on the redistribution of heat from the low latitudes to the high latitudes,” she said. “It makes sense, even though we can’t fully pinpoint how it’s linked. But it makes sense that there’s a link between the change in the gradient and the change in variability.”

Today, climate seems only to be moving in one direction — toward a warmer globe. The Arctic in particular is warming twice as fast as the planet as a whole, further shrinking the differences between polar and tropical temperatures. The difference today, however, is the current upswing is man-made, caused by human emissions of carbon dioxide and other heat-trapping gases.

“Right now, we have a forced warming. We are putting in CO2, and this drives up the temperature,” she said. “The reason for an individual swing in the past, we can’t decipher to that degree.”

Climate variability is “a key part of how you transition out of an ice age,” Texas A&M atmospheric scientists Andrew Dessler told Seeker. Knowing how climate might have fluctuated in the past can help scientists determine whether any of today’s warming is the result of natural forces, Dessler said.

“Natural variability does add to whatever humans are doing to the climate,” Dessler said. “To the extent there may be large long-timescale variability, that complicates the efforts to address climate change, because it’s something that’s out of our control.”

The last ice age saw glaciers covering most of the British Isles and Scandinavia and much of northern Europe. In North America, they reached south of present-day Chicago, gouging out the Great Lakes in the process. The ice reached a height of several miles, and their retreat affected climate as far south as Antarctica, Tyler Jones, a geochemist at the University of Colorado’s Institute of Arctic and Alpine Research, told Seeker.

Core samples taken from the West Antarctic Ice Sheet hold a 30,000-year temperature record. Jones and his colleagues used a laser spectroscope to analyze those core samples for signs of change, comparing the pattern they found to the pattern of radio waves on an oscilloscope.

“We found that there was a large, abrupt decline in the signal strength 16 thousand years ago,” he said. Climate models found that decline “was largely caused by the gradually lowering height of the ice sheet that sat over North America during the last ice age.”

“When there is a large ice sheet over North America, the circulation of the atmosphere becomes very different than today,” he said. “In the tropics, for example, the dominant rainfall patterns shifted east, creating a grassland-type ecosystem in Indonesia, rather than the rainforests we see today. This change in the rainfall, in turn, can be linked to the processes that cause year to year climate variability in West Antarctica.”

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Cretaceous ‘Monster Spider’ Had Modern and Primitive Features, Including a Tail

The arachnid C. yingi preserved in amber, with its tail visible

When a fossil dealer showed paleontologist Di-Ying Huang a blurry photo of his latest offering — a leggy creature entombed in amber — the scientist's eyes widened. Despite the poor-quality image, Huang, a professor at the Chinese Academy of Sciences, knew that the specimen was unique.

The creature had fangs, 8 legs, and a long tail that was at least twice the size of the rest of its body.

The specimen and another piece of fossil-containing amber were acquired for the academy's Nanjing Institute of Geology and Paleontology. Word spread among academics about the bizarre find, and Bo Wang, another professor at the academy, obtained two more similar pieces of fossil-containing amber.

Analysis of the four fossils resulted in a scientific rarity. Two independent research teams have simultaneously announced the discovery of a new species, a 100-million-year old arachnid, which has been named Chimerarachne yingi, aka "Monster Spider." Both papers are published in the journal Nature Ecology & Evolution.

"The most interesting feature of C. yingi is that it has both a tail and spinnerets," Wang told Seeker. "It is from a very primitive group, and their relatives were present before 250 million years ago."

He felt extremely surprised, he said, “because I never imagined that we could find this key fossil from the Cretaceous, only 100 million years ago."

Close-up of one of the C. yingi specimens

"Only" refers to the fact that the arachnid exhibits very primitive features for its age, such as its telson, or tail. The tail resembles that of modern whip scorpions.

"Maybe the tail originally had a sensory function," Wang said, "but when spiders changed to lifestyles like being sit-and-wait predators, or having webs, the tail was no longer really needed and became lost."

Another early feature of spiders was a segmented abdomen. Most species lost the segmentation over evolutionary time.

Reconstruction of C. yingi

Like today's spiders, however, C. yingi appears to have been venomous, given what look to be glands for venom production. The arachnid was small — less than half of an inch long — and had six eyes and four pairs of legs. ("Monster" refers more to its unusual mix of characteristics, rather than to its size.) The spinnerets were also similar to those of modern spiders.

Spiders began spinning silk much earlier than Monster Spider's lifetime. The world's oldest known spider dates to about 315 million years ago. Spiders might have first used silk to wrap their eggs, or to line their constructed tunnels, the researchers theorize.

The earliest known spider preserved in amber comes from what is now Lebanon and dates to approximately 130 million years ago. C. yingi, however, hailed from what is now northern Myanmar, formerly known as Burma, an area famous for its amber.

"Spiders are very common in amber," Wang said. "Considering the huge amount of Burmese amber, there are only 4 specimens of C. yingi, so C. yingi is extremely rare."

Wang and his team believe that the new species should be classified in the order Araneae, making it a true spider. Wang explained that C. yingi exhibits two key features only present in Araneae: a male pedipalp (appendage) modified for sperm transfer, and well-defined spinnerets.

Ecological reconstruction of C. yingi

Huang and his team do not believe that C. yingi was a true spider, although they came up with the Monster Spider moniker. They conducted CT-scans of the two other specimens and instead suggest that the arachnid be classified in the order Uraraneida.

Huang explained that the order refers to close relatives of spiders that are now extinct.

If additional evidence in the future proves their conclusion to be correct, then the fossil record of Uraraneida has just been extended some 170 million years toward the present. This, in turn, would mean that these spider-like arachnids and actual spiders co-existed for a large fraction of their evolutionary history.

Additionally, if C. yingi falls within Uraraneida, then organs for spinning silk and the modified male pedipalps are not unique to spiders.

Future research could solve the mystery, and reveal more about Monster Spider's behavior.

Clues could be the other inclusions within the pieces of amber, which Huang's colleague Gustavo Hormiga from the George Washington University described for Seeker.

One of the C. yingi specimens showing some of the amber inclusions

Collectively, accounting for all four specimens, the inclusions are millipedes, mite nymphs, a beetle, a fly, a springtail, many tiny plant parts, and more.

Read more at Seeker

Language previously unknown to linguists discovered in Southeast Asia

Jedek is an Austroasiatic language spoken by 280 people in northern Peninsular Malaysia.

A previously unknown language has been found in the Malay Peninsula by linguists from Lund University in Sweden. The language has been given the name Jedek.

"Documentation of endangered minority languages such as Jedek is important, as it provides new insights into human cognition and culture," says Joanne Yager, doctoral student at Lund University.

"Jedek is not a language spoken by an unknown tribe in the jungle, as you would perhaps imagine, but in a village previously studied by anthropologists. As linguists, we had a different set of questions and found something that the anthropologists missed," says Niclas Burenhult, Associate Professor of General Linguistics at Lund University, who collected the first linguistic material from Jedek speakers.

The language is an Aslian variety within the Austroasiatic language family and is spoken by 280 people who are settled hunter-gatherers in northern Peninsular Malaysia.

The researchers discovered the language during a language documentation project, Tongues of the Semang, in which they visited several villages to collect language data from different groups who speak Aslian languages.

The discovery of Jedek was made while they were studying the Jahai language in the same area.

"We realised that a large part of the village spoke a different language. They used words, phonemes and grammatical structures that are not used in Jahai. Some of these words suggested a link with other Aslian languages spoken far away in other parts of the Malay Peninsula," says Joanne Yager.

The community in which Jedek is spoken is more gender-equal than Western societies, there is almost no interpersonal violence, they consciously encourage their children not to compete, and there are no laws or courts. There are no professions either, rather everyone has the skills that are required in a hunter-gatherer community. This way of life is reflected in the language. There are no indigenous words for occupations or for courts of law, and no indigenous verbs to denote ownership such as borrow, steal, buy or sell, but there is a rich vocabulary of words to describe exchanging and sharing.

"There are so many ways to be human, but all too often our own modern and mainly urban societies are used as the yardstick for what is universally human. We have so much to learn, not least about ourselves, from the largely undocumented and endangered linguistic and cultural riches that are out there," states Niclas Burenhult.

Joanne Yager and Niclas Burenhult have spent long periods of time working with speakers of Aslian languages. This is necessary in order to systematically study, observe and document the languages -- it is not enough to simply conduct interviews.

"This work depends on devoted field workers with a strong passion for discovering more about linguistic diversity," explains Niclas Burenhult.

Read more at Science Daily

Reduced energy from the sun might occur by mid-century: Now scientists know by how much

Magnetic loops gyrate above the sun, March 23-24, 2017.

The Sun might emit less radiation by mid-century, giving planet Earth a chance to warm a bit more slowly but not halt the trend of human-induced climate change.

The cooldown would be the result of what scientists call a grand minimum, a periodic event during which the Sun's magnetism diminishes, sunspots form infrequently, and less ultraviolet radiation makes it to the surface of the planet. Scientists believe that the event is triggered at irregular intervals by random fluctuations related to the Sun's magnetic field.

Scientists have used reconstructions based on geological and historical data to attribute a cold period in Europe in the mid-17th Century to such an event, named the "Maunder Minimum." Temperatures were low enough to freeze the Thames River on a regular basis and freeze the Baltic Sea to such an extent that a Swedish army was able to invade Denmark in 1658 on foot by marching across the sea ice.

A team of scientists led by research physicist Dan Lubin at Scripps Institution of Oceanography at the University of California San Diego has created for the first time an estimate of how much dimmer the Sun should be when the next minimum takes place.

There is a well-known 11-year cycle in which the Sun's ultraviolet radiation peaks and declines as a result of sunspot activity. During a grand minimum, Lubin estimates that ultraviolet radiation diminishes an additional seven percent beyond the lowest point of that cycle. His team's study, "Ultraviolet Flux Decrease Under a Grand Minimum from IUE Short-wavelength Observation of Solar Analogs," appears in the publication Astrophysical Journal Letters and was funded by the state of California.

"Now we have a benchmark from which we can perform better climate model simulations," Lubin said. "We can therefore have a better idea of how changes in solar UV radiation affect climate change."

Lubin and colleagues David Tytler and Carl Melis of UC San Diego's Center for Astrophysics and Space Sciences arrived at their estimate of a grand minimum's intensity by reviewing nearly 20 years of data gathered by the International Ultraviolet Explorer satellite mission. They compared radiation from stars that are analogous to the Sun and identified those that were experiencing minima.

The reduced energy from the Sun sets into motion a sequence of events on Earth beginning with a thinning of the stratospheric ozone layer. That thinning in turn changes the temperature structure of the stratosphere, which then changes the dynamics of the lower atmosphere, especially wind and weather patterns. The cooling is not uniform. While areas of Europe chilled during the Maunder Minimum, other areas such as Alaska and southern Greenland warmed correspondingly.

Lubin and other scientists predict a significant probability of a near-future grand minimum because the downward sunspot pattern in recent solar cycles resembles the run-ups to past grand minimum events.

Despite how much the Maunder Minimum might have affected Earth the last time, Lubin said that an upcoming event would not stop the current trend of planetary warming but might slow it somewhat. The cooling effect of a grand minimum is only a fraction of the warming effect caused by the increasing concentration of carbon dioxide in the atmosphere. After hundreds of thousands of years of CO2 levels never exceeding 300 parts per million in air, the concentration of the greenhouse gas is now over 400 parts per million, continuing a rise that began with the Industrial Revolution. Other researchers have used computer models to estimate what an event similar to a Maunder Minimum, if it were to occur in coming decades, might mean for our current climate, which is now rapidly warming.

Read more at Science Daily

Ants: Master manipulators for biodiversity, or sweet treats

The top three aphids (small green and two large blackish green) are green morphs, and the lower two aphids (small red with an ant and a large brownish green) are red morphs.

Symbiotic ants manipulate aphid reproduction rates to achieve a specific mix of green and red aphids, maintaining the inferior green aphids which produce the ants' favorite snack.

Ants and aphids coexist in a symbiotic relationship that benefits both species. Ants protect aphids from predators, such as lady bugs and wasps, and aphids secrete nutritious honeydew for ants to eat.

The aphid species Macrosiphoniella yomogicola comes in two "morphs" with distinct colors: red and green. When there is more than one physical trait of the same species, it is called polymorphism. Typically, competition for survival would lead to one morph dominating and the others disappearing from the gene pool. However, this rule can be broken in a few circumstances, including if an ant benefits from maintaining a mixture of color morphs.

Previously, Associate Professor Eisuke Hasegawa of Hokkaido University and his colleagues had determined that Lasius japonicus ants prefer the nutrient-rich honeydew produced by green morphs. They also found that ants were most attracted to and most vigorously protected colonies with 65% green and 35% red aphids.

In a new study published in the journal Scientific Reports, Hasegawa and his students, including Saori Watanabe, investigated how population growth of aphid morphs differs with or without the presence of ants. They found that ants actively manipulate morph populations by improving the reproduction rate of the inferior morph.

In field experiments without the ants' presence, the red morphs had a much higher and superior reproduction rate than green morphs. Thus, red aphids should dominate. However, when ants were introduced to the experiment, the green morph reproduction rate equalized with the red morphs.

The experimental evidence matches what researchers find in the wild: red and green morphs coexisting on the same plant shoots attended by ants.

What remains a mystery is this: if the ants prefer the green morphs' honeydew, why keep the red morphs around at all? Hasegawa explains, "We theorize that the red morphs are able to provide a benefit that the green morphs can't, such as suppressing the development of lower buds on host plants. This might help both the red and green aphids survive and reproduce throughout more of the year, which could maximize long-term harvest of honey-dew from the green aphids."

Read more at Science Daily

Viruses -- lots of them -- are falling from the sky

Viruses and bacteria fall back to Earth via dust storms and precipitation. Saharan dust intrusions from North Africa and rains from the Atlantic.

An astonishing number of viruses are circulating around the Earth's atmosphere -- and falling from it -- according to new research from scientists in Canada, Spain and the U.S.

The study marks the first time scientists have quantified the viruses being swept up from the Earth's surface into the free troposphere, that layer of atmosphere beyond Earth's weather systems but below the stratosphere where jet airplanes fly. The viruses can be carried thousands of kilometres there before being deposited back onto the Earth's surface.

"Every day, more than 800 million viruses are deposited per square metre above the planetary boundary layer -- that's 25 viruses for each person in Canada," said University of British Columbia virologist Curtis Suttle, one of the senior authors of a paper in the International Society for Microbial Ecology Journal that outlines the findings.

"Roughly 20 years ago we began finding genetically similar viruses occurring in very different environments around the globe," says Suttle. "This preponderance of long-residence viruses travelling the atmosphere likely explains why -- it's quite conceivable to have a virus swept up into the atmosphere on one continent and deposited on another."

Bacteria and viruses are swept up in the atmosphere in small particles from soil-dust and sea spray.

Suttle and colleagues at the University of Granada and San Diego State University wanted to know how much of that material is carried up above the atmospheric boundary layer above 2,500 to 3,000 metres. At that altitude, particles are subject to long-range transport unlike particles lower in the atmosphere.

Using platform sites high in Spain's Sierra Nevada Mountains, the researchers found billions of viruses and tens of millions of bacteria are being deposited per square metre per day. The deposition rates for viruses were nine to 461 times greater than the rates for bacteria.

"Bacteria and viruses are typically deposited back to Earth via rain events and Saharan dust intrusions. However, the rain was less efficient removing viruses from the atmosphere," said author and microbial ecologist Isabel Reche from the University of Granada.

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