NASA's Opportunity rover spotted an odd Martian rock that looked like a doughnut on Jan. 8. Four days earlier, however, the rock wasn't there at all. So how did the rock appear? Alien rock throwers? A nearby meteorite impact?
The truth is much less surprising. Scientists working with the intrepid robot have just confirmed that the rock (called Pinnacle Island) was simply kicked up by one of Opportunity's wheels as it made its way across the planet's surface.
"Once we moved Opportunity a short distance, after inspecting Pinnacle Island, we could see directly uphill an overturned rock that has the same unusual appearance," Opportunity deputy principal investigator Ray Arvidson, of Washington University in St. Louis, said in a statement. "We drove over it. We can see the track. That's where Pinnacle Island came from."
The rock stirred up enough controversy that a concerned citizen even filed a lawsuit against the space agency, claiming that NASA failed to properly investigate a possible fungus growing on the Red Planet.
Although researchers figured out where the rock came from, there are other weird aspects of the Pinnacle Island tale. Using Opportunity's tools, mission scientists have discovered that the rock has very high levels of sulfur and manganese. Both of those elements are water-soluble, suggesting that they were concentrated in the rock due to the "action of water," NASA officials said.
"This may have happened just beneath the surface relatively recently, or it may have happened deeper below ground longer ago and then, by serendipity, erosion stripped away material above it and made it accessible to our wheels," Arvidson said.
The rock is located in a spot on "Murray Ridge" along the wall of Endeavour Crater, where Opportunity is spending the Martian winter. Now that the rover is done examining Pinnacle Island, the Opportunity team is planning to drive the rover uphill to check out exposed rock layers on a different part of the Martian surface.
"We are now past the minimum solar-energy point of this Martian winter," Opportunity project manager John Callas, of NASA's Jet Propulsion Laboratory in Pasadena, Calif., said in a statement. "We now can expect to have more energy available each week. What's more, recent winds removed some dust from the rover's solar array. So we have higher performance from the array than the previous two winters."
A region deep inside the brain controls how quickly people make decisions about love, according to new research at the University of Chicago.
The finding, made in an examination of a 48-year-old man who suffered a stroke, provides the first causal clinical evidence that an area of the brain called the anterior insula "plays an instrumental role in love," said UChicago neuroscientist Stephanie Cacioppo, lead author of the study.
In an earlier paper that analyzed research on the topic, Cacioppo and colleagues defined love as "an intentional state for intense [and long-term] longing for union with another" while lust, or sexual desire, is characterized by an intentional state for a short-term, pleasurable goal.
In this study, the patient made decisions normally about lust but showed slower reaction times when making decisions about love, in contrast to neurologically typical participants matched on age, gender and ethnicity. The findings are presented in a paper, "Selective Decision-Making Deficit in Love Following Damage to the Anterior Insula," published in the journal Current Trends in Neurology.
"This distinction has been interpreted to mean that desire is a relatively concrete representation of sensory experiences, while love is a more abstract representation of those experiences," said Cacioppo, a research associate and assistant professor in psychology. The new data suggest that the posterior insula, which affects sensation and motor control, is implicated in feelings of lust or desire, while the anterior insula has a role in the more abstract representations involved in love.
In the earlier paper, "The Common Neural Bases Between Sexual Desire and Love: A Multilevel Kernel Density fMRI Analysis," Cacioppo and colleagues examined a number of studies of brain scans that looked at differences between love and lust.
The studies showed consistently that the anterior insula was associated with love, and the posterior insula was associated with lust. However, as in all fMRI studies, the findings were correlational.
"We reasoned that if the anterior insula was the origin of the love response, we would find evidence for that in brain scans of someone whose anterior insula was damaged," she said.
In the study, researchers examined a 48-year-old heterosexual male in Argentina, who had suffered a stroke that damaged the function of his anterior insula. He was matched with a control group of seven Argentinian heterosexual men of the same age who had healthy anterior insula.
The patient and the control group were shown 40 photographs at random of attractive, young women dressed in appealing, short and long dresses and asked whether these women were objects of sexual desire or love. The patient with the damaged anterior insula showed a much slower response when asked if the women in the photos could be objects of love.
Scientists on NASA's Interstellar Boundary Explorer (IBEX) mission, including a team leader from the University of New Hampshire, report that recent, independent measurements have validated one of the mission's signature findings -- a mysterious "ribbon" of energy and particles at the edge of our solar system that appears to be a directional "roadmap in the sky" of the local interstellar magnetic field.
Unknown until now, the direction of the galactic magnetic field may be a missing key to understanding how the heliosphere -- the gigantic bubble that surrounds our solar system -- is shaped by the interstellar magnetic field and how it thereby helps shield us from dangerous incoming galactic cosmic rays. "Using measurements of ultra-high energy cosmic rays on a global scale, we now have a completely different means of verifying that the field directions we derived from IBEX are consistent," says Nathan Schwadron, lead scientist for the IBEX Science Operations Center at the UNH Institute for the Study of Earth, Oceans, and Space. Schwadron and IBEX colleagues published their findings online today in Science.
Establishing a consistent local interstellar magnetic field direction using IBEX low-energy neutral atoms and galactic cosmic rays at ten orders of magnitude higher energy levels has wide-ranging implications for the structure of our heliosphere and is an important measurement to be making in tandem with the Voyager 1 spacecraft, which is in the process of passing beyond our heliosphere.
"The cosmic ray data we used represent some of the highest energy radiation we can observe and are at the opposite end of the energy range compared to IBEX's measurements," says Schwadron. "That it's revealing a consistent picture of our neighborhood in the galaxy with what IBEX has revealed gives us vastly more confidence that what we're learning is correct."
How magnetic fields of galaxies order and direct galactic cosmic rays is a crucial component to understanding the environment of our galaxy, which in turn influences the environment of our entire solar system and our own environment here on Earth, including how that played into the evolution of life on our planet.
Notes David McComas, principal investigator of the IBEX mission at Southwest Research Institute and coauthor on the Science Express paper, "We are discovering how the interstellar magnetic field shapes, deforms, and transforms our entire heliosphere."
To date, the only other direct information gathered from the heart of this complex boundary region is from NASA's Voyager satellites. Voyager 1 entered the heliospheric boundary region in 2004, passing beyond what's known as the termination shock where the solar wind abruptly slows. Voyager 1 is believed to have crossed into interstellar space in 2012.
Interestingly, when scientists compared the IBEX and cosmic ray data with Voyager 1's measurements, the Voyager 1 data provide a different direction for the magnetic fields just outside our heliosphere.
That's a puzzle but it doesn't necessarily mean one set of data is wrong and one is right. Voyager 1 is taking measurements directly, gathering data at a specific time and place, while IBEX gathers information averaged over great distances -- so there is room for discrepancy. Indeed, the very discrepancy can be used as a clue: understand why there's a difference between the two measurements and gain new insight.
When individuals from different groups interbreed, their offspring's DNA becomes a mixture of the DNA from each admixing group. Pieces of this DNA are then passed along through subsequent generations, carrying on all the way to the present day. Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Oxford University and University College London (UCL) have now produced a global map detailing the genetic histories of 95 different populations across the world, spanning the last four millennia.
The interactive world map that is accessible via the internet, details the histories of genetic mixing between each of the 95 populations across Europe, Africa, Asia and South America. It shows likely genetic impacts of historical events including European colonialism, the Mongol Empire, the Arab slave trade and European traders near the Silk Road mixing with people in China.
The study, published this week in Science, is the first to simultaneously identify, date and characterise genetic mixing between populations. To do this, the researchers developed sophisticated statistical methods to analyse the DNA of 1490 individuals in 95 populations around the world. "DNA really has the power to tell stories and uncover details of humanity's past," said Simon Myers of Oxford University's Department of Statistics and Wellcome Trust Centre for Human Genetics, co-senior author of the study. "Because our approach uses only genetic data, it provides information independent from other sources. Many of our genetic observations match historical events, and we also see evidence of previously unrecorded genetic mixing. For example, the DNA of the Tu people in modern China suggests that in around 1200CE, Europeans similar to modern Greeks mixed with an otherwise Chinese-like population. Plausibly, the source of this European-like DNA might be merchants travelling the nearby Silk Road."
The powerful technique, christened 'Globetrotter', provides insight into past events such as the genetic legacy of the Mongol Empire. Historical records suggest that the Hazara people of Pakistan are partially descended from Mongol warriors, and this study found clear evidence of Mongol DNA entering the population during the period of the Mongol Empire. Six other populations, from as far west as Turkey, showed similar evidence of genetic mixing with Mongols around the same time.
"What amazes me most is simply how well our technique works," said Garrett Hellenthal of the UCL Genetics Institute, lead author of the study. "Although individual mutations carry only weak signals about where a person is from, by adding information across the whole genome we can reconstruct these mixing events. Sometimes individuals sampled from nearby regions can have surprisingly different sources of mixing. For example, we identify distinct events happening at different times among groups other than the Hazara sampled within Pakistan, with some inheriting DNA from sub-Saharan Africa, perhaps related to the Arab Slave Trade, another from East Asia, and yet another from ancient Europe. Nearly all our populations show mixing events, so they are very common throughout recent history and often involve people migrating over large distances."
The team used genome data for all 1490 individuals to identify 'chunks' of DNA that were shared between individuals from different populations. Populations sharing more ancestry share more chunks, and individual chunks give clues about the underlying ancestry along chromosomes.
The mustache is an accessory of great responsibility, for with it comes great power. Take, for instance, Tom Selleck in Three Men and a Baby, Alex Trebek in pre-2001 Jeopardy, and Freddie Mercury in all of eternity forever and always. Facial forces to be reckoned with, for sure, but to the best of my knowledge none of these men has ever maimed a rival with the mustache itself.
Amateurs, says the Emei mustache toad. This dapper little amphibian doesn’t just walk into the breeding season unarmed. For one chaotic month a year in China, males grow extremely sharp facial spikes, which they use to shank rivals for the choicest nesting sites.
Some 90 percent of all males end up injured. Victors win the right to mate. Losers shuffle away and seriously consider never growing a mustache again, because maybe it wasn’t a good idea in the first place and they were just curious how it would look, like that one time when I was in high school.
Their weapons are called, no joke, nuptial spines, and they’re made of keratin — the same stuff as your fingernails. The spines grow straight through the toad’s skin, and although they will at times pop off in combat, they’ll simply sprout once again, only to fall off at the end of the breeding season.
And if you think that mustache is handsome, wait until you hear about the toad’s other transformations. Its forearms will actually buff up considerably in the mating season, like a bro during a Jersey Shore summer. This, according to evolutionary biologist Cameron Hudson, likely aids both in combat and in amplexus: the amphibian sexy-time, in which strong forelimbs will help the male grasp the female.
In addition, “their skin also becomes much looser, folded, and wrinkled,” Hudson said in an email to WIRED. “We think that this transformation allows them to remain underwater for longer periods (since the breeding, combat and nest guarding is all aquatic) by increasing oxygen absorption through the skin’s larger surface area.”
This species is, after all, a terrestrial one that like most frogs and toads chooses to reproduce in water, which is ideal for their external fertilization. Males hole up in nest sites, the most sought-after being caves of overhanging rock where eggs can be safely deposited. Periodically surfacing to breathe, they will defend these dens zealously like tiny Smaugs, only without the fire-breathing on account of being underwater.
“Generally the battles occur when one male approaches the nest site of another male and tries to go in through the entrance,” said Hudson. “They usually start with the nest occupant trying to block the entrance and shove the intruder away with their head (also while vocalizing). As the fight escalates the intruder will try to grapple the owner and rotate him out of position.”
The combatants keep their heads low, aiming to flip one another. “Usually the fight ends when a male holds his opponent vertically,” added Hudson, “grappling him around the waist and stabbing him in the abdomen. The ‘grappler’ tries to bash his opponent against nearby rocks.”
These battles are vicious, as you can see in the video below. Strangely, though, losing doesn’t necessarily doom a toad’s chances of mating. “There are some potentially interesting questions about male strategy that came up during my research,” said Hudson, “in that fighting is energetically expensive, so sometimes it might be in your best interest to lose and find a new site (if they are available).”
Unusual for an amphibian, these males are considerably larger than the females. And technically that’s odd for any sort of creature, because the females of most animal species on this planet dwarf the males. Of course we and almost all other mammals are exceptions here, but our branch is only a tiny one on the tree of life. Elsewhere in the animal kingdom, females generally have more body mass because producing and maintaining eggs requires much more space and energy than does producing sperm.
What tends to reverse that size bias are selection pressures on the males to grow larger to fight for the right to mate, as Hudson believes the mustache toad has done. Though Hudson finds that being big doesn’t always guarantee victory in battle, large males do indeed have the highest reproductive success. This indicates that females prefer their fellas bulky, or that while larger males can suffer loses, they’re generally better able to control nest sites.
Here’s how it all goes down. When females show up to the river-bottom breeding grounds, the males call out, ideally from the comfort of a sweet nest. If a female is interested, she’ll approach and bump him on the chin with her head, as if to say, “I’m not one of those girls who hates mustaches.” He’ll then rub his chin back and forth across her head — which Hudson reckons is some sort of stimulation — as the pair moves around the nest for the female to scope the surroundings.
“Once they have decided to mate, the male grasps around [her] hips and turns sideways,” said Hudson. “As she begins to lay the eggs, he sticks them to the roof of the nest with his foot. The pair then rotates in a circle, which creates the distinct doughnut-shaped egg mass.”
But say you don’t find your nest before the females arrive. Interestingly, if a male and female have already done that tango and a new male shows up and evicts the successful male, he won’t destroy the already-fertilized eggs. This is quite strange from an evolutionary perspective: Helping protect offspring not of your own making is a waste of energy, not to mention that the young will compete with your own.
Hudson theorizes a few reasons why this may be. “The first is that females may prefer nests with eggs. It’s possible that they take this as a sign of a successful male, and good breeding partner. Another reason may be that if you have more eggs in the nest, yours are less likely to get eaten by a predator, or infected by water molds.”
Dear Science Communication Professionals: We have a problem.
Earlier this month, the Bill Nye vs. Ken Ham creationism “debate” received a disproportionate amount of press coverage. Considering there really is no debate to be had when it comes to the science of evolution, for bad or for worse, Nye faced a hostile audience at the Creationist Museum, Kentucky, in the hope to score some scientific points against Ham’s literal translation of the Bible and his absurd assertion that the world was created in 6 days and that the universe is 6,000 years old. In my opinion (an opinion shared by other science communicators), the Nye vs. Ham debate did little for science outreach, was all about who sounded more convincing and only gave creationists some free advertising.
And then, today, the National Science Foundation (NSF) delivered news of a pretty shocking poll result: around 1-in-4 Americans are unaware that the Earth orbits the sun. Let’s repeat that: One in four Americans — that represents one quarter of the population — when asked probably the most basic question in science (except, perhaps, “Is the Earth flat?” Hint: No.), got the answer incorrect. Suddenly I realized why the Nye vs. Ham debate was so popular.
But wait! I hear you cry, perhaps the NSF poll was flawed? Perhaps the poll sample was too small? Sadly not. The NSF poll, which is used to gauge U.S. scientific literacy every year, surveyed 2,200 people who were asked 10 questions about physical and biological sciences. On average, the score was 6.5 out of 10 — barely a passing grade. But for me personally, the fact that 26 percent of the respondents were unaware the Earth revolves around the sun shocked me to the core.
Perhaps I’m expecting too much of the U.S. education system? Perhaps this is just an anomaly; a statistical blip? But then, like the endless deluge of snow that is currently choking the East Coast, another outcome of the same poll appeared on the foggy horizon of scientific illiteracy: The majority of young Americans think astrology is a science.
What the what? Have I been transported back to the Dark Ages? Astrology, of course, is not a science, it is a spiritual belief system at best and at worst a pseudoscience driven by charlatans and the tabloid press. The positions of the stars and planets in the sky do not affect my mood and my horoscope has little bearing on the kind of person I am. 92 percent of the people of China, one of the birthplaces of astrology, know that astrology is bunk. Really America, get your act together.
Unfortunately, if we are to use the “Is astrology a science?” as a litmus test for scientific literacy, things are looking grim. In 2004, 66 percent of the American public said astrology was bunk. Every year since then, that majority has slipped — by 2012, only 55 percent of Americans considered astrology “not at all scientific.” Probably of most concern is the fact that only 42 percent of young respondents aged between 18-24 said astrology is “not at all scientific.”
But there is a small glimmer of hope. According to the same NSF poll, the vast majority of Americans seem to love science. Although they returned woeful test results, it seems America is hungry to learn about science and that science funding is essential for the well-being of the nation. But I’m now concerned about what America thinks science really is, especially in light of that astrology result. Also, just because the U.S. public wants to learn, can they find the institutions that will actually teach real science?
Dinosaurs went from drab to colorful fab just before 150 million years ago, according to a study published in the latest issue of the journal Nature.
The "Wizard of Oz"-type moment in evolution appears to coincide with the emergence of feathers.
Researchers determined this after studying pigment-containing organelles known as melanosomes. These specialized structures within cells in living organisms contain melanin, which is the most common light-absorbing pigment found in animals.
"Black, brown and grey colors are melanin-based," co-author Julia Clarke told Discovery News. "In birds, melanin-based colors include a slightly larger range of reddish brown, brown, black, grey, black and many forms of iridescence."
Clarke is an associate professor at the University of Texas at Austin's Jackson School of Geosciences. She and her colleagues compared the melanosomes of 181 diverse living animals, including birds, mammals and reptiles, as well as 13 fossil specimens and all previously published data on this subject.
Before it was determined that diversity in the shape and size of melanosomes is associated with the evolution of melanin-based color in non-avian dinosaurs, birds and mammals. This diversity in dinos happened suddenly, just as small, meat-eating maniraptoran dinosaurs were evolving feathers, the study found.
"This shift is not seen close to the origin of dinosaur 'fuzz' or 'protofeathers,' but is only associated with feathers," Clarke said. "The shift seems abrupt and occurs before the origin of anything we would call avian flight."
While she and her team are not sure why dinosaurs experienced such a color explosion, Clarke said the dramatic change could have facilitated mate selection. Just as pretty, colorful birds today catch our eye, colorful exteriors would have probably grabbed the attention of non-flying dinosaurs and literal 'early birds' seeking sexual partners.
Many of the genes involved in the melanin color system are also tied to basic functions such as food intake, reproductive behaviors, the "fight or flight" process and other things. So the researchers believe that the color explosion in certain dinosaurs might have been linked to larger changes in their anatomy and metabolism.
"What is most exciting is that tracking color could potentially offer insight into dinosaur physiology," Clarke said.
The research could, for example, help to reveal the precise bodily changes that took place just as non-avian dinosaurs were evolving into birds, and why those changes occurred in the first place.
Color for color's sake is also of interest, allowing us to better recreate and envision what long-extinct animals looked like. This has been a challenge for researchers studying rather drab-looking fossils.
"The presence of pigment must not be confused with color, as even with a specific pigment being recognized, there are/were many factors that contribute to an organism's entire color palette," paleontologist Phillip Manning of the University of Manchester told Discovery News.
A birth that took place long before the first dinosaurs emerged can be seen now, thanks to a newly unearthed fossil.
The fossil, discovered in China and described in PLOS ONE, freezes in time the moment that an Ichthyosaur gave birth 248 million years ago.
To give you an idea of how long ago that was, the first dinosaurs emerged some 18 million years after this birthing event.
Ichthyosaurs evolved from terrestrial reptiles and moved to the water. This particular individual and her offspring belonged to the genus Chaohusaurus, the earliest known Mesozoic marine reptile.
“The study reports the oldest vertebrate fossil to capture the ‘moment’ of live-birth, with a baby emerging from the pelvis of its mother,” said author Ryosuke Motani, of the University of California at Davis, in a press release. “The 248-million-year old fossil of an ichthyosaur suggests that live-bearing evolved on land and not in the sea.”
He and his colleagues suspect live birth began on land because the infants were coming out head first, a posture associated with land-dwelling animal births.
In addition to showing the earliest live birth of an ancient marine reptile, the specimen is also thought to contain the oldest known fossil embryos of Mesozoic marine reptiles.
This mom and her babies are obviously long gone. At least one ichthyosaur species, however, survived until the Early Cretaceous, about 90 million years ago. While it’s long gone too, it shows how successful these animals — as a group — were during their lengthy time on our planet.
Dozens of skeletons might lie beneath the Uffizi Gallery in Florence, according to archaeologists who have dug up a medieval mass grave near the renowned museum.
Exposed during work to build an elevator in an area designed to house an expanded section of the Uffizi’s exhibit space, the skeletons belong to more than 60 individuals of various ages and genders who probably succumbed to a devastating epidemic.
“It appears they all died at the same time. Multiple graves contain up to 10 bodies, certainly buried in a hurry. Within the graves we also found some coins, all dating between the end of the 4th and the beginning of the 5th century A.D.,” Carlotta Cianferoni, director of Florence’s National Archaeological Museum, told Discovery News.
“The coins provide a rather accurate temporal reference, but of course we need to wait the results of the anthropological analysis and radiocarbon dating,” Cianferoni said.
According to the archaeologists, who have worked at the site for the past five months, the position and the way the bodies were laid in the graves indicate an emergency situation.
“The burials were made in a hurry and with the clear purpose of using less possible space. Bodies were laid side by side in opposite directions, feet against heads, while small, empty spaces were fitted with the bodies of children,” Cianferoni said.
The well-preserved skeletons were found near Piazza del Grano, a few feet away from the gallery and the Arno river, in an area which was probably subjected to floods in antiquity.
“We have unearthed just a small part of the necropolis. We cannot rule out the cemetery extended up to where the Uffizi Gallery now stands,” Cianferoni said.
Since the skeletons lack of signs of wounds or malnutrition, the archaeologists believe the cause of death was a “lethal epidemic,” such as the plague, cholera, dysentery or the flu.
A parasite found in cat feces, scooped out from litter boxes and flushed down the toilet, is showing up in Arctic beluga whales in a finding that is one of the most graphic examples of the world’s changing ecosystems, scientists said.
The finding, announced Thursday, comes with a warning for Inuit residents who eat whale meat. The cat parasite, known as Toxoplasma gondii, is infectious.
Toxoplasmosis, also known as "kitty liter disease" is the leading cause of infectious blindness in humans. It can be fatal to fetuses and people and animals with compromised immune systems.
How the parasite made its way into western Arctic Belugas is no mystery, say biologists Michael Grigg and Stephen Raverty, with the University of British Columbia.
Arctic ice, once a formidable barrier for distant pathogens, is melting, allowing an unprecedented passageway between the far north and warmer climates in the lower latitudes, the scientists said at the American Association for the Advancement of Science meeting in Chicago.
"What we're seeing with the big thaw is the liberation of pathogens gaining access to vulnerable new hosts and wreaking havoc," Grigg, who also works with the U.S. National Institutes of Health, said in a statement.
The parasitic highway is open in both directions. The researchers also reported that a parasite known as Sarcocystis, previously found only in the Arctic, is responsible for killing 406 grey seals in the north Atlantic in 2012.
The new strain of the parasite, now named Sarcocystis pinnipedi, also is responsible for the deaths of an endangered Steller sea lion, seals, Hawaiian monk seals, walruses, polar and grizzly bears in Alaska and as far south as British Columbia, Grigg said.
