Genes tell story of birdsong and human speech

His office is filled with all sorts of bird books, but Duke neuroscientist Erich Jarvis didn't become an expert on the avian family tree because of any particular interest in our feathered friends. Rather, it was his fascination with how the human brain understands and reproduces speech that brought him to the birds.

"We've known for many years that the singing behavior of birds is similar to speech in humans -- not identical, but similar -- and that the brain circuitry is similar, too," said Jarvis, an associate professor of neurobiology at the Duke University Medical School and an investigator at the Howard Hughes Medical Institute. "But we didn't know whether or not those features were the same because the genes were also the same."

Now scientists do know, and the answer is yes -- birds and humans use essentially the same genes to speak.

After a massive international effort to sequence and compare the entire genomes of 48 species of birds representing every major order of the bird family tree, Jarvis and his colleagues found that vocal learning evolved twice or maybe three times among songbirds, parrots and hummingbirds.

Even more striking is that the set of genes involved in each of those song innovations is remarkably similar to the genes involved in human speaking ability.

The findings are part of a package of eight scientific papers in a Dec. 12 special issue of Science and 21 additional papers appearing nearly simultaneously in Genome Biology, GigaScience and other journals. Jarvis' name appears on 20 papers and he is a corresponding author for 8 of them.

Jarvis co-led the Avian Phylogenomics Consortium with Guojie Zhang of the National Genebank at BGI in China and the University of Copenhagen and M. Thomas P. Gilbert of the Natural History Museum of Denmark. His Duke lab contributed to preparing samples, sequencing and annotating the genomes, performing the analyses and coordinating the overall project.

The Jarvis lab in the Bryan Research Building prepared DNA of many of the species, pulling it from little chunks of frozen, pink bird flesh collected over the past 30 years by museums and other institutions around the world. To ensure the DNA being sequenced really belonged to the Golden-collared manakin and not an undergraduate lab assistant, the lab has been kept spotlessly clean and many of its tools are used only once, to avoid the possibility of subsequent contamination.

"We change gloves a lot," said Carole Parent, the lab research analyst who set up a DNA isolation pipeline for the next stage of the project to sequence still more birds and supervised sample prep with a team of Duke undergrads and a student from East Chapel Hill High School.

All of this meticulous and somewhat tedious work has given Jarvis and hundreds of colleagues around the world a crack at an unprecedented amount of genomic data generated by BGI in China. The whole-genome comparison of the 48 bird species required new algorithms written at the University of Illinois and University of Texas that ran for 400 years of CPU time on three supercomputers in the U.S.

Of the 29 papers covering everything from penguin evolution to color vision, eight are devoted to bird song.

One of the Dec. 12 papers in Science found there is a consistent set of just over 50 genes that show higher or lower activity in the brains of vocal learning birds and humans. These changes were not found in the brains of birds that do not have vocal learning and of non-human primates that do not speak, according to this Duke team, which was led by Jarvis; Andreas Pfenning, a graduate of the Ph.D. program in computational biology and bioinformatics (CBB); and Alexander Hartemink, professor of computer science, statistical science and biology.

"This means that vocal learning birds and humans are more similar to each other for these genes in song and speech brain areas than other birds and primates are to them," Jarvis said.

These genes are involved in forming new connections between neurons of the motor cortex and neurons that control the muscles that produce sound.

A companion study by another CBB doctorate, Rui Wang, looked at the specialized activity of a pair of genes involved in the regions of the brain that control song and speech. This study, appearing in the Journal of Comparative Neurology, found that these genes are down- and up-regulated in one brain region of song-learning birds during the juvenile period of their vocal learning , changes that last into adulthood. This study, and that of Pfenning, hypothesize that changes in these genes could be critical for the evolution of song in birds and speech in humans.

"You can find those same genes in the genomes of all species, but they're active at much higher or lower levels in the specialized song or speech brain regions of vocal learning birds and humans," Jarvis said. "What this suggests to me is that when vocal learning evolves, there may be a limited way in which the brain circuits can evolve."

Another paper in Science from Duke, led by post-doc Osceola Whitney, Pfenning, Hartemink and Anne West, an associate professor of neurobiology, looked at gene activation in different areas of the brain during singing. This team found activation of 10 percent of the expressed genome during singing, with diverse activation patterns in different song-learning regions of the brain. The diverse gene patterns are best explained by epigenetic differences in the genomes of the different brain regions, meaning that individual cells in different brain regions can regulate genes at a moment's notice when the birds sing.

Among the three main groups of vocal learning birds, parrots are clearly different in their ability to mimic human speech. Mukta Chakraborty, a postdoc in the Jarvis lab, led a project that used the activity of some of the specialized genes to discover that the parrot's speech center is organized somewhat differently. It has what the researchers call a "song-system-within-a-song-system" in which the area of the brain with different gene activity for producing song has an outer ring of still more differences in gene expression.

Parrots are very social animals, Chakraborty said, and having the ability to quickly pick up "dialects" of parrot speech may account for their super-charged speech center. The "shell" or outer regions were found to be proportionally larger in the parrot species, which are believed to have the highest vocal, cognitive and social abilities. These species include Amazon parrots, the African Grey and the Blue and Gold Macaw.

Jarvis was also part of a team with Claudio Mello and his Ph.D. student Morgan Wirthlin at Oregon Health & Science University that found ten more genes that are unique to song-control regions of songbirds. This paper appears in BMC Genomics.

A paper in Science led by Zhang, Gilbert and Jarvis found the genomes of vocal learners are more rapidly evolving and have more chromosomal rearrangements compared to other bird species. This genomic comparison also found similar changes occurred independently in in the song-learning area of different birds' brains.

Jarvis said knowing more of this history of how speech evolved in birds makes vocal learning birds even more valuable model organisms for helping to answer the questions he and other researchers are addressing about human speech.

"Speech is difficult to study in human brains," he said. "Whales and elephants learn speech and songs, but they're too big to house in the lab. Now that we have a deeper understanding of how similar birdsong brain regions are to human speech regions at the genetic level, I think they'll be a better model than ever."

Jarvis' general exploration of the bird brain over his 16 years at Duke has also led to several unexpected discoveries unrelated to song.

In 2005, he and colleagues found a center of the brain in migratory birds that apparently enables sensing of magnetic fields through "night vision." That year he also led a revision of the understanding of bird brain organization and vertebrate brain evolution. Last year, he led a re-drawing of the geography of the bird brain based on analysis of 52 genes that are active in 23 areas of the brains of eight species of birds. This new map shows neuron groupings in the birds' brains to be organized in columns like the brains of humans and other mammals.

Read more at Science Daily

Oil-dwelling bacteria are social creatures in Earth's deep biosphere

Oil reservoirs are scattered deep inside Earth like far-flung islands in the ocean, so their inhabitants might be expected to be very different, but a new study led by Dartmouth College and University of Oslo researchers shows these underground microbes are social creatures that have exchanged genes for eons.

The study, which was led by researchers at Dartmouth College and the University of Oslo, appears in the ISME Journal.

The findings shed new light on the "deep biosphere," or the vast subterranean realm whose single-celled residents are estimated to be roughly equal in number and diversity to all the microbes inhabiting the surface's land, water and air. Deep microbial research may also help scientists to better understand life's early evolution on Earth and aid the search for life on Mars and other planets.

Some scientists support a "burial and isolation" scenario in which bacteria living in oil reservoirs are descendants of isolated bacterial communities buried with sediments that over time became oil reservoirs. "Instead, our analysis supports a more complex 'colonization' view, where bacteria from subsurface and marine populations have been continuously migrating into the oil reservoirs and influencing their genetic composition since ancient times," says co-author Olga Zhaxybayeva, an assistant professor at Dartmouth.

Since the 1980s, a growing number of microbial life forms have been discovered deep underground, but many questions remain, including when and how these microorganisms came to inhabit places where temperatures and pressure are extreme and nutrients and energy can be scarce. Microorganisms are the oldest form of life on Earth and continue to play a crucial role in the planet's ecosystem. Those bacteria dwelling underground live not off sunlight energy but Earth's inner heat, chemicals and nutrients.

In their new paper, researchers asked a number of questions, including: do buried bacteria adapt to living in oil reservoirs as they form from sediments? Do bacteria evolve in isolation, or do they migrate to oil reservoirs and exchange genes with surrounding bacteria, including surface ones introduced through drilling fluids used in oil production? The researchers analyzed 11 genomes of Thermotoga, an ancient lineage of heat-loving bacteria, taken from oil reservoirs in the North Sea and Japan and from hot water vents on the ocean floor near the Kuril Islands north of Japan, Italy and the Azores, an island chain west of Portugal. They also analyzed Thermotoga community DNA from the environment (so-called metagenomes) from North America and Australia that are available in public databases.

Read more at Science Daily

Earth's most abundant mineral finally has a name

An ancient meteorite and high-energy X-rays have helped scientists conclude a half century of effort to find, identify and characterize a mineral that makes up 38 percent of the Earth.

And in doing so, a team of scientists led by Oliver Tschauner, a mineralogist at the University of Las Vegas, clarified the definition of the Earth's most abundant mineral -- a high-density form of magnesium iron silicate, now called Bridgmanite -- and defined estimated constraint ranges for its formation. Their research was performed at the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility located at DOE's Argonne National Laboratory.

The mineral was named after 1964 Nobel laureate and pioneer of high-pressure research Percy Bridgman. The naming does more than fix a vexing gap in scientific lingo; it also will aid our understanding of the deep Earth.

To determine the makeup of the inner layers of the Earth, scientists need to test materials under extreme pressure and temperatures. For decades, scientists have believed a dense perovskite structure makes up 38 percent of the Earth's volume, and that the chemical and physical properties of Bridgmanite have a large influence on how elements and heat flow through the Earth's mantle. But since the mineral failed to survive the trip to the surface, no one has been able to test and prove its existence -- a requirement for getting a name by the International Mineralogical Association.

Shock-compression that occurs in collisions of asteroid bodies in the solar system create the same hostile conditions of the deep Earth -- roughly 2,100 degrees Celsius (3,800 degrees Farenheit) and pressures of about 240,000 times greater than sea-level air pressure. The shock occurs fast enough to inhibit the Bridgmanite breakdown that takes place when it comes under lower pressure, such as the Earth's surface. Part of the debris from these collisions falls on Earth as meteorites, with the Bridgmanite "frozen" within a shock-melt vein. Previous tests on meteorites using transmission electron microscopy caused radiation damage to the samples and incomplete results.

So the team decided to try a new tactic: non-destructive micro-focused X-rays for diffraction analysis and novel fast-readout area-detector techniques. Tschauner and his colleagues from Caltech and the GeoSoilEnviroCARS, a University of Chicago-operated X-ray beamline at the APS at Argonne National Laboratory, took advantage of the X-rays' high energy, which gives them the ability to penetrate the meteorite, and their intense brilliance, which leaves little of the radiation behind to cause damage.

The team examined a section of the highly shocked L-chondrite meteorite Tenham, which crashed in Australia in 1879. The GSECARS beamline was optimal for the study because it is one of the nation's leading locations for conducting high-pressure research.

Bridgmanite grains are rare in the Tenhma meteorite, and they are smaller than 1 micrometer in diameter. Thus the team had to use a strongly focused beam and conduct highly spatially resolved diffraction mapping until an aggregate of Bridgmanite was identified and characterized by structural and compositional analysis.

This first natural specimen of Bridgmanite came with some surprises: It contains an unexpectedly high amount of ferric iron, beyond that of synthetic samples. Natural Bridgmanite also contains much more sodium than most synthetic samples. Thus the crystal chemistry of natural Bridgmanite provides novel crystal chemical insights. This natural sample of Bridgmanite may serve as a complement to experimental studies of deep mantle rocks in the future.

Read more at Science Daily

San Francisco's Deadliest Shipwreck Found

In dark waters just outside the Golden Gate Bridge, archaeologists have pinpointed the final resting place of the worst shipwreck in San Francisco's history.

New sonar maps show for the first time the mud-covered grave of the SS City of Rio de Janeiro, nearly 300 feet (91 meters) below the surface. The steamer sank on Feb. 22, 1901, just before reaching its destination, with 210 people on board, most of them Chinese and Japanese immigrants.

"The overwhelming response looking at the imagery of the Rio is one of sadness," said James Delgado, director of maritime heritage for National Ocean and Atmospheric Administration's (NOAA) Office of National Marine Sanctuaries. When the ship sank, "it was front-page news all over the world. It was a terrible tragedy," he said.

The City of Rio spent two months at sea, making stops in Hong Kong; Yokohama, Japan; and Honolulu before returning to San Francisco. On the morning of the accident, pilot Frederick Jordan had been steering the 345-foot (105 m) steamer through the Golden Gate strait (three decades before construction on the bridge started). But under heavy fog, the City of Rio struck jagged rocks near Fort Point, at the southern end of the strait. The ship was badly damaged and sank within just 10 minutes, trapping many passengers riding in the cabin and in steerage. In total, 128 people were killed.

In the 1980s, a salvage team claimed to have found the shipwreck. However, the team lost its equipment trying to reach the underwater site, and later, it turned out that the coordinates the team recorded didn't match up with those of the wreck site, Delgado said.

Last month, the companies Hibbard Inshore and Bay Marine Services donated a research vessel and crew to NOAA for a day. The agency used the opportunity to look for the City of Rio using a 3D sonar device known as Echoscope developed by the company Coda Octopus. NOAA was able to find and map the City of Rio, and the crew even had time to map the nearby SS City of Chester, a wreck that was recently rediscovered.

The City of Chester, destined for Eureka, California, went down on Aug. 22, 1888, after colliding with the RMS Oceanic, a ship that was arriving from Asia. Of the 90 people on board, 16 were killed. Delgado and his team thought the City of Chester would be buried in mud, but instead, it's quite exposed, with its boilers and engines still mounted in place.

"You see the bones of the ship laid out," Delgado said. "You see the machinery in place in an environment that would otherwise be completely unknown and inaccessible."

In contrast, the City of Rio is in bad shape. The vessel is collapsing under a thick layer of mud. At some point since it sank, the ship's front half broke off and slid down a 65-foot (20 m) slope. Even without its mud coating, the ship would be nearly impossible to salvage with current technology because of its depth and the strong currents surrounding the wreck, Delgado said. In his view, the City of Rio is in a "sealed grave."

Read more at Discovery News

Behold! See Rosetta's Comet in True Color

Well … what did you expect? It wasn’t going to be green now, was it.

This newest photo release from the European Space Agency’s Rosetta spacecraft has got to be the biggest anticlimax from an otherwise thrilling mission so far. However, the science behind the photo completely eclipses Comet 67P/Churyumov-Gerasimenko’s monochrome surface.

“As it turns out, 67P/C-G looks dark grey, in reality almost as black as coal,” said Holger Sierks, from the Max Planck Institute for Solar System Research (MPS) and principal investigator for Rosetta’s OSIRIS instrument, in a Rosetta blog update today (Dec. 12).

Taken through OSIRIS’s three color filters of red, green and blue, this photographic version of the familiar comet is our first ‘true color’ view of the dusty surface since Rosetta arrived in orbit in August. Although there are some very slight color variations, the comet would look just like this to the human eye — predominantly dark grey.

OSIRIS stands for Optical, Spectroscopic, and Infrared Remote Imaging System, and the instrument has been painstakingly capturing every small detail on the comet’s surface.

When observed from afar, long before Rosetta arrived at 67P, astronomers had an idea that the cometary surface would have, on average, a greyish color. But on closer inspection, Rosetta mission scientists are surprised by how grey the body is, even on the finest of scales. This signifies that the comet’s nucleus has very little compositional variations on its surface.

One would normally expect to see a slightly blue hue over regions dominated with ice, for example. Although other instruments on Rosetta suggest there is an abundance of ice throughout the comet, its presence certainly isn’t seen by OSIRIS. Instead, 67P is homogeneously covered in a fine dust that gives it a very uniform appearance.

Read more at Discovery News

Mystery Solved for How Birds Lost Their Teeth

"DNA from the crypt" has revealed the lack of teeth in all living birds can be traced back to a common ancestor who lost its choppers about 116 million years ago.

The finding is reported in one of eight studies published today in Science by the Avian Phylogenomics Consortium, an international collaboration examining the evolution of living birds.

In total 23 papers are being simultaneously published this morning, revealing new insights into questions such as what makes a bird a bird; how colourful feathers and vocal learning developed; and the evolutionary tree of all avians.

The tooth study answers a question that has long baffled evolutionary biologists: did tooth loss in birds happen convergently across a number of bird lineages or through a common ancestor?

It uses data from whole-genome sequencing of 48 bird species that represent nearly all living bird orders, as well as the American alligator, a representative of Crocodylia (the closest living relatives of birds).

Co-author Professor Mark Springer, of the University of California Riverside, says it has been known that modern birds descended from a toothed ancestor since the discovery of Archaeopteryx in 1861.

Archaeopteryx lived around 150 million years ago and is considered a transitional species between dinosaurs and birds. Although it had wings, it also had jaws with sharp teeth and stood on two legs.

Later fossil finds also revealed animals with partial beaks, but in the back of the jaw they still had teeth.

Springer says this makes evolutionary sense.

"You can't expect that an ancestor would have gone through a stage when all of the teeth would have been lost, but there was no beak," Springer, of the Department of Biology, says.

"That would have made it too hard to do all the things they needed to do like feeding themselves or their young.

"Once you get that partial beak, then you can continue to lose the teeth more posterially until they become completely replaced by the beak."

However, he says the history of final tooth loss in the ancestry of modern birds has remained elusive for more than 150 years.

Mutant tooth genes the key

For the study the team looked for shared mutations in the six genes that are essential for the formation of dentin and enamel, the building blocks of teeth.

"Tooth formation is very complex in terms of the hundreds of genes involved … most of these genes are not only involved in tooth formation they are involved in other developmental processes as well."

The six genes they isolated were the "best candidates for being specific to teeth".

"If teeth are gone then natural selection should not maintain these genes," says Springer.

If the genes were found to be non-functioning due to mutations in all 48 bird species they studied, this would indicate loss through a common ancestor.

"We can then use this record of mutations to estimate when the teeth were in fact lost," he says.

The team, which also includes Professor Thomas Gilbert, a visiting academic at Curtin University in Western Australia, found enamel-related genes were disabled in the common ancestor of modern birds about 116 million years ago.

The researchers also examined the genomes of a number of toothless vertebrates including three turtles and four mammals (pangolin, aardvark, sloth, and armadillo) for these same mutations.

They found these vertebrates also had mutations in the dentin and enamel genes, making them non-functional.

By comparison all six genes were functional in the American alligator.

"Dead genes" are an important tool, says Springer. They are "chock full of information, it's like finding a fossil in the rocks".

"They are still in our genome, but full of these inactivating mutations so they don't function anymore.

"This DNA from the crypt is a powerful tool for unlocking secrets of evolutionary history."

Read more at Discovery News

Ancient Egyptian Coffin's Odd Art Hints at Brain Drain

An ancient Egyptian coffin with strange and amateurish decorations has been revealed, shedding light on a tumultuous period in Egyptian history when the Persian Empire was in control of the region.

In 525 B.C., Persian King Cambyses marched into Memphis, the Egyptian capital, inaugurating a period of Persian rule that would last for more than a century. The Persian Empire was a vast entity that stretched from modern-day Afghanistan to the west coast of Turkey. Ancient texts say that the Persian kings deported Egyptian artists and used them for building projects in Persia.

The coffin bears a series of unusual features that are likely related to the Persian Empire's deportation of artists.

"Many of the best artists in Egypt were taken by the Persians back to Persepolis and Susa as POWs and war booty -- you can see their work in those places. There seems to have been a dearth of masters for some time, so that fewer and fewer artists got proper training," Gayle Gibson, an Egyptologist and educator at Toronto's Royal Ontario Museum, told Live Science in an email.

Gibson presented the coffin at the Society for the Study of Egyptian Antiquities Scholars' Colloquium, which was held Nov. 13 to 16 in Toronto.

Odd features

There are several odd features on the coffin that reflect the lack of knowledge the ancient artist had, Gibson said.

For instance, the deceased is depicted lying on a funerary bed, and the bed has a human-headed bird called a Ba. Flying over the deceased is a winged snake wearing a crown associated with the goddess Hathor. Below them are four jars bearing the heads of the four Sons of Horus, but the jars have a "goofy" appearance, Gibson said.

To an Egyptologist, this is a bizarre scene, Gibson said. "This is the only funerary bed I know of with a Ba's head," she told the Toronto audience, also noting that "we have a winged snake with Hathor's crown -- very odd."

There are other oddities. The collar wrapped around the top of the coffin contains two creatures that look almost fishlike. The artist was likely trying to draw falcons, a symbol of the god Horus, but drew them very poorly, Gibson said.

A Mehen snake, a protective deity in Egypt, is also poorly drawn and actually stops at one point and starts in another, something strange for a protective deity. "The artist doesn't really understand the purpose of the Mehen snake," Gibson said.

Mike Sigler, a collector and Egyptian antiquities enthusiast who lives in Kentucky and now owns the coffin, sent a picture to Live Science showing that the ancient artist clumsily attempted to correct an error in an alternating pattern by scratching out an image of a scepter.

Ancient brain drain

Although there is no longer a mummy in the coffin, its inscriptions say that it belonged to someone named Denit-ast, or Dent-ast, likely a woman. Radiocarbon dating of her coffin indicates that she lived at a time when her country was under Persian control.

Ancient texts tell tales of the deportation of Egyptian artists to Persia during this time. Diodorus Siculus, who died around 30 B.C., said that Cambyses, the conqueror of Egypt, transferred both precious metals and artists from Egypt to Persia.

Additionally, Persian King Darius I bragged about the Egyptian artists he acquired in a text describing the construction of his palace at Susa. "The goldsmiths who wrought the gold, those were Mede and Egyptians. The men who wrought the wood, those were Sardians and Egyptians … the men who adorned the wall, those were Medes and Egyptians" Darius said (translation by Roland Kent).

Authentication

Gibson told the Toronto audience that when she first showed the coffin to other Egyptologists, some expressed skepticism and wondered if it was a fake created before Sigler owned it.

However, radiocarbon dating places the coffin in the Persian period and analysis of its wood indicates that it's sycamore, a wood that was commonly used in ancient Egypt. Additionally, an analysis of the coffin's blue pigments found that the pigment was Egyptian blue, which indicates that the coffin is authentic, Gibson said.

Sigler purchased the coffin in August 2013 from the Edgar L. Owen gallery, which sold it on behalf of a private collector. Paperwork that Sigler received indicates that the collector acquired it from the European art market in 1980. Its history before that is unknown.

Gibson is well known for her Egyptological work. In the 1990s she helped identify a mummy in Niagara Falls, Canada, as likely being that of pharaoh Ramesses I. The mummy was later returned to Egypt with full military honors.

Given Gibson's reputation, Sigler sought her out and asked her for help in understanding the coffin's strange features.

Despite its odd features, Gibson believes the coffin is not a fake. "I think there is really no doubt that this one is genuine," she said.

Read more at Discovery News

Mysterious X-Ray Signal Could Reveal Dark Matter (Blogpost #5000)

Astronomers may finally have detected a signal of dark matter, the mysterious and elusive stuff thought to make up most of the material universe.

While poring over data collected by the European Space Agency's XMM-Newton spacecraft, a team of researchers spotted an odd spike in X-ray emissions coming from two different celestial objects — the Andromeda galaxy and the Perseus galaxy cluster.

The signal corresponds to no known particle or atom and thus may have been produced by dark matter, researchers said.

"The signal's distribution within the galaxy corresponds exactly to what we were expecting with dark matter — that is, concentrated and intense in the center of objects and weaker and diffuse on the edges," study co-author Oleg Ruchayskiy, of the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, said in a statement.

"With the goal of verifying our findings, we then looked at data from our own galaxy, the Milky Way, and made the same observations," added lead author Alexey Boyarsky, of EPFL and Leiden University in the Netherlands.

Dark matter is so named because it neither absorbs nor emits light and therefore cannot be directly observed. But astronomers know dark matter exists because it interacts gravitationally with the "normal" matter we can see and touch.

And there is apparently a lot of dark matter out there: Observations of star motion and galaxy dynamics suggest that about 80 percent of all matter in the universe is "dark," exerting a gravitational force but not interacting with light.

Researchers have proposed a number of different exotic particles as the constituents of dark matter, including weakly interacting massive particles (WIMPs), axions and sterile neutrinos, hypothetical cousins of "ordinary" neutrinos (confirmed particles that resemble electrons but lack an electrical charge).

The decay of sterile neutrinos is thought to produce X-rays, so the research team suspects these may be the dark matter particles responsible for the mysterious signal coming from Andromeda and the Perseus cluster.

If the results — which will be published next week in the journal Physical Review Letters — hold up, they could usher in a new era in astronomy, study team members said.

Read more at Discovery News

The Adorable Mexican Mole Lizard Has a Disgusting Reputation

Don’t you be coy with me, you little pervert.

Down in Baja California there crawls a beast so bizarre, so cruel, so foul, that the mere mention of it sends locals scurrying. It’s an opportunist, said to attack humans at their most vulnerable moment: potty time.

Should you be foolish enough to drop trou and answer the call of nature in the wilderness, you’ll find the beast will “enter your body by the most unspeakable means,” said Carl Franklin, a herpetologist at the University of Texas at Arlington. “And it’ll rip your guts, shred them to pieces.” The death is slow, not to mention embarrassing.

OK, it’s not true—the creature, a reptile called the Mexican mole lizard, is in fact totally adorable and completely harmless—but it sure is a powerful myth. A few years ago Franklin was driving through Baja with his wife searching for the critters, and pulled up to two cowboys. He handed them a picture of the mole lizard and asked if they’d seen any lately, and “they just twisted up their faces in disgust, and they went over and saw my license plate is from Texas.” They then proceeded to admonish him for coming to their country for such things.

“I get to the next town, 10 miles away,” Franklin recalls, “and I see a young guy walking on the side of the road and I stop and I ask him and he just starts backing up, and he says, ‘Hey mister we’re all really good people here. My uncle just called me and told me you were coming.’”

The Mexican mole lizard eats just about anything small enough and soft enough. Except ice cream. It never really comes across ice cream.

Which is all to say, finding Mexican mole lizards is hard on its own—they’re about the size of a large earthworm—and much more so when you’ve alienated the locals. Regardless, this is one of the strangest, most mysterious reptiles on Earth (it technically isn’t a lizard or a snake, but sits in a category all its own, the amphisbaenians), with powerful front limbs and rear limbs that have vanished save for vestigial bones you can only make out on X-rays. Strangely, the three species of Mexican mole lizard are the only amphisbaenians that haven’t lost all their limbs entirely. Why that is, no one is quite sure. Stranger still, each species has a different number of fingers: one with three, another with four, and the last with five.

Part of the problem with finding these things is that they’re subterranean, burrowing through sandy soil with their reinforced heads while scooping back debris with those well-developed claws. It’s no wonder, then, that they’ve lost their back legs. Often in evolution it makes sense for a structure to evolve away if it’s no longer useful, or indeed a detriment, sparing you the energy and resources and time needed to build it. As a bonus, what you don’t have can’t get injured—or in the case of the Mexican mole lizard’s hind limbs, perhaps losing lose legs means you can move better through the soil.

The creature’s eyes are quite beady and underdeveloped. “If you’re basically a mute inhabitant in a dark underworld, you gotta figure that touch and taste and smell are going to be the three keen senses,” said Franklin. “So anything like vibrations, they certainly can feel, but finding mates and even locating prey, it’s going to be chemosensory” cues, which they pick up with their tongue.

And as for prey, these critters are going after pretty much anything soft they can get their tiny conical teeth on: a whole range of small insects, as well as things like cockroach eggs—and good on ‘em for that. Franklin may be the only person in the world who has legally obtained them to raise in captivity, and he can attest that they’ll happily eat things that don’t even live with them in the wild, including earthworms. “I swatted a little spider one day and tossed it in,” he said. “They ate everything except for his fangs. So why that wasn’t eaten, I don’t know. Maybe they could smell it and decided it wasn’t tasteful.”

Mexican mole lizards spend so much time underground in search of food that they lack the melanin that gives organisms their color. “These guys, man they would need lots of SPF, because they’re really fair skinned,” and accordingly emerge only at dusk, Franklin said. You can even shine a flashlight right through them (which is technically known as “candling,” by the way).

And these things are about as comfortable above ground as we are below it. It’s hard to classify their method of locomotion. The critter isn’t using its limbs much, and it isn’t quite slithering. It’s actually anchoring itself at points along its body, then pushing forward. This makes sense underground: By contracting itself against the walls of its burrow, the Mexican mole lizard can slowly inch forward, leaving its limbs free to shove loose soil back.

Those powerful claws help the creature shovel dirt out of the way.

Now, a year ago I featured another charming little subterranean creature, the pink fairy armadillo from Argentina. Like the Mexican mole lizard, it faces a problem living underground: thermoregulation. As a burrower, you’re pretty much stuck with the temperature of the soil. You can’t seek shade or water to cool down. The armadillo has solved this problem by turning its shell into a radiator of sorts. If it overheats, it can pump blood into the shell, cooling itself down. Conversely, if it’s too cold, it can pump the blood back into its body to raise its core temperature.

The Mexican mole lizard isn’t blessed with such a shell, so how does it regulate its body temperature? For the moment, Franklin isn’t sure, though he notes that he’ll find them in the roots of vegetation, perhaps taking advantage of the cooler soil under the plant’s shade. “So they would just move from one site to the next for thermoregulatory needs, is my educated guess.”

Read more at Wired Science

'Pseudoscorpions' Discovered in Grand Canyon Cave

Two new species of so-called pseudoscorpions have been discovered in a cave on the northern rim of the Grand Canyon.

The elusive creatures, which have adapted to their lightless environment by losing their eyes, were discovered in Grand Canyon-Parashant National Monument, which abuts the better-known Grand Canyon National Park.

Unlike true scorpions, these scorpion imposters lack a tail with a venomous stinger. Instead, the arachnids use venom-packed stingers in their pincers to immobilize their prey, study author J. Judson Wynne, an assistant research professor in the Department of Biological Sciences at Northern Arizona University, in Flagstaff, wrote in an email.

The tiny cave where the team discovered the new species — just 250 feet (76 meters) in length — nevertheless supports the highest diversity of cave-adapted arthropods of any known cave in the Grand Canyon-Parashant National Monument, Wynne said.

The researchers first discovered the two false scorpions during expeditions in a cave along the north rim of the Grand Canyon, between 2005 and 2007. But it took years before the team identified the species as unique.

"Contrary to popular belief, rarely are we in the field, collect an animal and then brandish our grubby field flasks of whiskey to toast a new species discovery," Wynne told Live Science in an email.

To confirm the scorpion lookalikes were a new species, the team had to take them back to a taxonomic specialist, who analyzed all the details of the species and pored over all the existing data on similar species. In this case, the team found that one of the species had a thickened pair of legs and a mound on the pincer, while another had a much deeper pincer than other pseudoscorpions — qualifying each as a distinct species, study co-author Mark Harvey, senior curator at the Western Australian Museum in Perth, said in an email.

The creatures, dubbed Hesperochernes bradybaughii and Tuberochernes cohni, respectively, are about 0.12 inches (3 millimeters) long and feed on tiny invertebrates, including springtails, book lice, mites and possibly cricket nymphs. Many of their prey are just one-fourth the length of a grain of rice.

The two species are named after Jeff Bradybaugh, an advocate for cave research and the former superintendent of Grand Canyon-Parashant National Monument, and Theodore Cohn, an entomologist who identified a new genus of cave cricket and passed away in 2013.

The fact that two separate species of pseudoscorpion can live in the cave while competing for the same food source suggests the cave supports a robust food web. The cave is one of the largest roosts of crickets in northern Arizona, and the pseudoscorpion prey feed on the cricket "frass," or poop, as well as the fungus that grows on the poop. The cave is also home to a bizarre, eyeless fungus beetle that feeds on the poop fungus.

At one time, the pseudoscorpions' ancestors lived in the desert environment outside the cave, but they have since adapted to hunting in an environment devoid of light, losing their eyes and gaining an elongated bodies in the process.

In general, pseudoscorpions are odd creatures. Not only are their pincers good for immobilizing prey, they also help the insects hitchhike to new locales.

"They will grasp onto another animal such as birds, mammals and even other insects. They hold on and can be transported long distances," Wynne said.

Read more at Discovery News