Australian scientists say they’ve found the fossil of a new species of giant platypus that walked the Earth between 5 and 15 million years ago.
Up until now, the fossil record of the platypus indicated that only one species of the animal lived on Earth at any one time. The new study suggests this new extinct giant platypus species, called Obdurodon tharalkooschild, is a side-branch of the platypus family, rather than its direct ancestor.
The platypus is a mammal with a duck-like bill, thick fur that’s much like an otter’s, and a tail similar to a beaver’s. It has webbed feet and reproduces by laying eggs rather than giving birth like other mammals.
The animal was so odd that in 1798 when Captain John Hunter, then the governor of New South Wales, Australia, sent a pelt of a platypus along a sketch of the animal to scientists in Great Britain, the British researchers at first thought it was a joke or a hoax.
The Australian researchers were able to identify this new species of platypus from a single fossilized tooth found in the Riversleigh World Heritage Area of northwest Queensland, Australia.
“Monotremes (platypuses and echidnas) are the last remnant of an ancient radiation of mammals unique to the southern continents,” said Rebecca Pian, lead author of the study. “A new platypus species, even one that is highly incomplete, is a very important aid in developing understanding about these fascinating mammals.”
The fossilized tooth’s size leads researchers to believe this ancient platypus was about a meter in length, two times the length of today’s platypus. Today, the male platypus grows to a length of about 50 cm while females grow to about 43 cm in length.
“Like other platypuses, it was probably a mostly aquatic mammal and would have lived in and around the freshwater pools in the forests that covered the Riversleigh area millions of years ago,” said Dr. Suzanne Hand of the University of New South Wales, a co-author of the study.
The ancient Obdurodon tharalkooschild was able to eat its prey with a set of well-developed teeth, unlike today’s platypus which has horny pads in its mouth instead.
The extinct platypus probably ate a varied menu that included not only crayfish and other freshwater crustaceans, but also small vertebrates such as lungfish, frogs, and small turtles.
The researchers named the prehistoric animal Obdurodon, Greek for “lasting (obdurate) tooth,” because its teeth are unlike today’s platypus species. Tharalkooschild was given in honor of a story told by Indigenous Australians about the creation and origin of the platypus.
The direction in which a dog wags its tail can communicate its emotional state to other canines, according to a new study published in Current Biology.
The Italian research team behind the study says dogs recognize, and respond accordingly, whether other canines wag their tails to the right or to the left.
The reason dogs understand the right versus left tail wag, according to the researchers, is because they have asymmetrically organized brains, meaning that the left and right sides of our brains are each responsible for controlling different things, much like humans.
In an earlier study, the researchers found dogs tend to wag their tails to the right when they feel positive, such as when they see their owners. Dogs wag their tails to the left when they experience negative emotions, such as feelings that might be triggered by an unfriendly dog or some other kind of danger.
The researchers say that this left and right tail wagging behavior is because of what’s taking place in the canine’s brains. A wag to the right is brought on by activation on the left side of its brain, while activity in the right side of the brain produces a wag to the left.
While this right versus left wagging behavior means something to other dogs, the researchers say that they’re probably not purposely displaying this behavior to communicate with each other. Instead they say it’s just an automatic response due to left side or right side brain activation. But the team also points out that this behavior could serve a very helpful purpose to people like dog owners and veterinarians as another way to better understand what’s going on with the animal.
Compilation of videos shown to test dogs – left, right, no tail wagging – (Current Biology, Siniscalchi et al.)
To make their findings the researchers showed their dog subjects videos of other dogs either wagging their tails to the left or right. When the test dogs saw a video of a dog wagging its tail to the left, their heart rates increased and they appeared a bit nervous. However, when the dogs saw another animal wagging its tail to the right, they remained calm.
“The direction of tail wagging does in fact matter, and it matters in a way that matches hemispheric activation,” said Giorgio Vallortigara of the Center for Mind/Brain Sciences of the University of Trento. “In other words, a dog looking to a dog wagging with a bias to the right side—and thus showing left-hemisphere activation as if it was experiencing some sort of positive/approach response—would also produce relaxed responses. In contrast, a dog looking to a dog wagging with a bias to the left—and thus showing right-hemisphere activation as if it was experiencing some sort of negative/withdrawal response—would also produce anxious and targeting responses as well as increased cardiac frequency. That is amazing, I think.”
Both the United States and India are gearing up for unmanned missions to Mars.
India will launch its first interplanetary spacecraft when the Indian Space Research Organization (ISRO) sends its Mars Orbiter Mission (MOM) to the Red Planet on Nov. 5. The spacecraft will be launched from the Satish Dhawan Space Centre located in Sriharikota, Andhra Pradesh, India.
According to ISRO, one of MOM’s main objectives is to allow the Indian space program to develop the technologies required to design, plan, manage and operate an interplanetary mission.
Once the MOM spacecraft arrives at Mars in September 2014, it will drop into orbit around the planet. Throughout its nearly year-long mission the MOM will explore the Martian surface and atmosphere.
Meanwhile, NASA is making final preparations to launch a new unmanned mission to Mars that will allow scientists on Earth to examine the Red Planet’s atmosphere in greater detail.
Lift-off for the Mars Atmosphere and Volatile Evolution mission (MAVEN) is currently scheduled on Monday, Nov. 18 from Cape Canaveral Air Force Station in Florida.
“The MAVEN mission is a significant step toward unraveling the planetary puzzle about Mars’ past and present environments,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington. “The knowledge we gain will build on past and current missions examining Mars and will help inform future missions to send humans to Mars.”
Once it arrives at Mars, also in September 2014, and eases into its elliptical science orbit, the MAVEN will observe all of the Red Planet’s latitudes. The spacecraft is expected to cruise around Mars at an altitude of between 158 and 6,115 km above its surface.
During its mission, MAVEN will also perform five of what NASA calls “deep dip maneuvers,” that will send the spacecraft down to an altitude of only 125 km above the surface of Mars, which scientists say is the lower boundary of the planet’s upper atmosphere.
When you look at yourself in the mirror, do you ever wonder why you look the way you do? Do you also wonder what biological processes were at work when it came time to shape and sculpt your face, which is as individual and unique as a fingerprint?
These little pieces of DNA help switch on, or boost the expression of specific genes that control the development of the face and head while in utero. What’s interesting about these little influential bits of DNA is that a gene enhancer doesn’t have to be found anywhere close to the genes it works on and, in some cases, doesn’t even have to be located on the same chromosome.
Of course, there are a number of hereditary factors, such as when a child resembles a parent, that help determine appearance. The researchers, who outlined their findings in the journal “Science,” said the gene enhancer fine-tunes the genetics to give your face its final unique look. Even with identical twins, there are subtle differences in appearance.
“Our results suggest it is likely there are thousands of enhancers in the human genome that are somehow involved in craniofacial development,” said Axel Visel, a geneticist with Berkeley Lab’s Genomics Division, who led the research. “We don’t know yet what all of these enhancers do, but we do know that they are out there and they are important for craniofacial development.”
Scientists have previously been able to identify some of the genetic flaws that can cause birth defects, such as a cleft lip or palate, but haven’t been able to fully understand what genetic factors are responsible for normal, subtle differences in appearance.
In the past, Visel and his colleagues were able to map gene enhancers in the heart, brain and other vital organs. The researchers said their studies showed that gene enhancers can control their targets from across distances of hundreds of thousands of base pairs, which are each two chemical bases that scientists consider to be the fundamental components of the DNA double helix.
To find out if these gene enhancers have the same type of long-distance effect on the development of the head and face, the researchers studied transgenic mice or those that had been genetically modified.
They were able to identify more than 4,000 possible gene enhancer sequences they think play a role in fine-tuning the genes responsible for developing and defining the head and face.
A later analysis of their data showed that removing a few of these individual craniofacial enhancers can cause changes to the shape of the head and/or face.
“Our results also offer an opportunity for human geneticists to look for mutations specifically in enhancers that may play a role in birth defects, which in turn may help to develop better diagnostic and therapeutic approaches,” said Visel.
While the researchers continue their own research, they are also working with geneticists to carry out specialized searches to look for mutations within the enhancer sequences of humans with craniofacial birth defects.
An international team of scientists claim that their recent research could rewrite the history of human evolution.
The researchers suggest that instead of our early human ancestors belonging to different evolutionary species such as Homo habilis, Homo rudolfensis or Homo erectus, they are all actually of the same species, but just happen to look a bit different from each another.
Writing in the journal Science, the scientists from Georgia, Switzerland, Israel and the U.S. came to their conclusions after studying a 1.8-million-year-old skull from the early Pleistocene epoch that was unearthed in Dmanisi, Georgia.
According to the researchers, the skull they studied, called Skull 5, is not like other fossils of the Homo genus. Skull 5, they said, reveals a combination of a braincase that’s about 546 cubic centimeters along with a long face and large teeth.
Despite having limb proportions and the body size of a modern human, the researchers said that the small braincase of Skull 5 indicates that this early human ancestor had a small brain.
The skull was found with the remains of four other human ancestors along with other material that included an assortment of animal fossils and some stone tools.
The researchers said this was a unique find since all of the unearthed material could be associated with the same time period and location.
In examining and analyzing “Skull 5”, the researchers said that they found that the differences between the various fossils were no more noticeable than those between five modern humans or five chimpanzees.
“Had the braincase and the face of Skull 5 been found as separate fossils at different sites in Africa, they might have been attributed to different species,” said Christoph Zollikofer from the Anthropological Institute and Museum in Zurich, Switzerland and a co-author of the report. “That’s because Skull 5 unites some key features, like the tiny braincase and large face, which had not been observed together in an early Homo fossil until now.”
Researchers previously have typically considered variations among Homo fossils as an indication that they were of different species.
But those involved with this recent study say that their findings suggest that fossils of various early members of the human family, all originating in Africa, are part of one evolving lineage, probably what is known as Homo erectus. Previous research indicates that this now extinct hominid lived as recently as 143,000 to about 1.8 million years ago.
“[The Dmanisi finds] look quite different from one another, so it’s tempting to publish them as different species,” explained Zollikofer. “Yet we know that these individuals came from the same location and the same geological time, so they could, in principle, represent a single population of a single species.”
Checking the African fossil record, the researchers said that they also noticed a similar pattern and range of variation in the African fossil record so they figured that it was safe to assume that there was a single Homo species at that time in Africa too.
Furthermore, the researchers also found that since the hominid fossils recovered from the Dmanisi site are so similar to those found in Africa, they theorize that they are also both of the same species.
While the Georgian dig site is already providing opportunities for researchers to “compare and contrast” the physical characteristics of a number of human ancestors that happened to be in the same place and time, scientists expect even more evidence to be uncovered, since the site has only been partially excavated.
Chicago researchers have made significant progress developing prosthetic limbs that can feel and touch.
This research could lead to a direct interface with the brain that could someday allow those who have lost limbs to, not only manipulate objects, but also to be able to touch and feel again.
“To restore sensory motor function of an arm, you not only have to replace the motor signals that the brain sends to the arm to move it around, but you also have to replace the sensory signals that the arm sends back to the brain,” said Sliman Bensmaia of the University of Chicago. “We think the key is to invoke what we know about how the brain of the intact organism processes sensory information, and then try to reproduce these patterns of neural activity through stimulation of the brain.”
The research by the Chicago team is part of a project, under way since 2006, called Revolutionizing Prosthetics at the Defense Advanced Research Projects Agency (DARPA). Researchers hope to create a modular artificial upper limb that will restore an amputee’s natural motor control and sensation.
The work being done by the Chicago research team focuses on developing the sensory aspects of the prosthetic limbs. Their experiments have been conducted with monkeys since the animals’ sensory systems are similar to humans.
The researchers said they’ve been able to identify patterns of neural activity which occur when an object is being manipulated and then artificially replicate those patterns.
In their first experiment, the researchers wanted to learn more about sensing where the skin was touched. They trained the test monkeys to recognize several types of physical contact with their fingers and then connected electrodes to parts of the monkey’s brains related to each of their fingers. Instead of using actual physical touches, they substituted them with electrical stimulation directed to those specific areas of their brains. As a result, the researchers found that the monkeys reacted to the electrical stimulation the same way they did with actual physical contact.
The next area the researchers wanted to concentrate on was sense of pressure on the skin. They came up with an algorithm that would produce the proper amount of electrical current to artificially produce the sensation of pressure. As in their first experiment, the researchers found their test animals responded the same way whether the sensation was actually felt through their fingers or reproduced artificially.
Finally, the researchers looked into the natural sensations that are felt when a hand first touches or releases an object. Since this series of events also produces bursts of activity in the brain, the research team was able to provide direct stimulation to the brain that also duplicated those sensations.
The experiments helped the scientists develop computer instructions to be incorporated into a robotic prosthetic arm. They said that these instructions, working with the robotic appendage and through a neural interface, will be able to deliver sensory responses that mimic natural sensations of touch directly to the brain.
With the progress that the researchers have made with their animal experimentation, they hope to soon be able to test their devices during clinical trials with humans.
Two recently released studies have shed new light on ancient Europeans.
Taking maternally-inherited mitochondrial DNA samples from bones and teeth of the skeletons of 364 people who lived about 5,000 years ago in what is now Central Europe, researchers in one study said that they were able to reconstruct the first detailed genetic history of modern-day Europeans.
The research that is allowing scientists to map the history of human migration is the result of a 7 – 8 year collaborative effort between the Australian Centre for Ancient DNA (ACAD), at the University of Adelaide, the Johannes Gutenberg University Mainz, the State Heritage Museum in Halle (Germany), and the National Geographic Society’s Genographic Project.
“This is the largest and most detailed genetic time series of Europe yet created, allowing us to establish a complete genetic chronology,” said the study’s joint-lead author Dr. Wolfgang Haak of ACAD. “Focusing on this small but highly important geographic region meant we could generate a gapless record, and directly observe genetic changes in ‘real-time’ from 7,500 to 3,500 years ago, from the earliest farmers to the early Bronze Age.”
The scientists said that their research revealed a pattern of genetic replacement in people who lived in central Europe over a period of several thousand years. This indicates that some rather intricate changes went into producing today’s Europeans.
They also pointed out that noticeable changes in the genetic composition of those living in a region we now know as Germany was the result of at least four stages of migration and settlement of people who not only came from a long regarded path through the Near East, but also from Western and Eastern Europe.
“None of the dynamic changes we observed could have been inferred from modern-day genetic data alone, highlighting the potential power of combining ancient DNA studies with archaeology to reconstruct human evolutionary history,” said Haak.
The other study that examined the migration and settlement of Europe was led by scientists from Johannes Gutenberg University Mainz in Germany and the University College London in Great Britain.
This team of researchers, who also studied DNA taken from ancient human bones, found that native European “hunter-gatherers” – those who got their food from wild game and plants – lived side by side with immigrant farmers for about 2,000 years and were able to maintain their individual lifestyle much longer than was previously thought.
“It is commonly assumed that the Central European hunter-gatherers disappeared soon after the arrival of farmers”, said Dr. Ruth Bollongino, lead author of the study. “But our study shows that the descendants of Mesolithic Europeans maintained their hunter-gatherer way of life and lived in parallel with the immigrant farmers, for at least 2,000 years. The hunter-gathering lifestyle thus only died out in Central Europe around 5,000 years ago, much later than previously thought.”
Historians have said that farming or agriculture originated about 10,000 to 12,000 years ago in an area of the Near East known as the “fertile crescent” of Mesopotamia which included parts of today’s Iran, Iraq, Turkey, Syria, Lebanon, and Israel. Descendants of those first farmers brought agriculture to Europe about 7,500 years ago.
“Until around 7,500 years ago all central Europeans were hunter-gatherers,” said Professor Mark Thomas, professor of evolutionary genetics at the University College London, and a co-author of the study. “They were the descendants of the first wave of our species to arrive in Europe, around 45,000 years ago. They survived the last Ice Age and the warming that started around 10,000 years ago. And now it seems they also survived the initial wave of farmers spreading across Europe from the southeast of the continent.”
While previous archaeological research has provided evidence of some forms of interaction between the native hunter-gatherers and their neighboring immigrant farmers, not much was known about the scope and length of their dealings with each other.
The newly released study showed that the farmers and hunter-gatherers did stay close to each other in proximity, maintained contact for thousands of years and even buried their dead in the same cave.
But the interaction between the two cultures apparently did have some limits. The researcher’s investigation revealed that while hunter-gatherer women sometimes married into families in the farming communities, the opposite may not have been true since no genetic lines of farmer women have been found in hunter-gatherers.
“This pattern of marriage is known from many studies of human populations in the modern world,” explained Burger. “Farmer women regarded marrying into hunter-gatherer groups as social demotion.”
The scientists said that their study showed that individually neither the hunter-gatherers nor the farmers represent the common ancestry of today’s Europeans, but instead came from a mix of both populations.
A team of South African scientists writing in the journal ‘Earth and Planetary Science Letters’ said that they have found the first evidence of a comet striking Earth 28 million years ago.
“Comets always visit our skies – they’re these dirty snowballs of ice mixed with dust – but never before in history has material from a comet ever been found on Earth,” said David Block, a member of the research team and a professor of the University of the Witwatersrand.
The researchers said that the comet shot into Earth’s atmosphere and blew up above what is now known as Egypt with blast that wiped out every living thing in its path.
As the fireball exploded it created a super-hot shock wave that heated the sand on the surface to about 2,000 degrees Celsius. The extreme heat and pressure formed a great quantity of yellow silica glass that was spread throughout a 6,000 square kilometer area of the Sahara that’s known as the Libyan Desert Glass strewn field.
A remarkable example of Libyan Desert Glass can be found on an ancient brooch of the Pharaoh Tutankhamun (King Tut) who ruled Egypt from 1332 BC to 1323 BC. Egyptian jewelers polished and carved a piece of the yellow silica to form the body of a scarab that is prominently featured on the brooch.
The first evidence of a comet strike, said the scientists, came in the form of a mysterious 30 gram black pebble that had been found in 1996 by an Egyptian geologist who had been exploring the strewn field.
The pebble now called the Hypatia stone, was named in honor of Hypatia of Alexandria, the first well-known female mathematician, astronomer and philosopher. The researchers said that the stone, which they described as being black, angular, shiny, incredibly hard and extremely fractured, is covered with microscopic diamonds that were created by the shock of the comet’s impact.
“Diamonds are produced from carbon bearing material. Normally they form deep in the earth, where the pressure is high, but you can also generate very high pressure with shock. Part of the comet impacted and the shock of the impact produced the diamonds,” said lead author Professor Jan Kramers of the University of Johannesburg.
After the South African team conducted a number of tests on the Hypatia stone, they concluded that the black pebble was not just an unusual type of meteorite but instead represented the very first known hand specimen of a comet nucleus.
The researchers said that comet material on Earth is incredibly rare. The only other comet fragments that had been found were microscopic dust particles found in the upper atmosphere and in some carbon-rich dust found in Antarctic ice.
“NASA and ESA (European Space Agency) spend billions of dollars collecting a few micrograms of comet material and bringing it back to Earth, and now we’ve got a radical new approach of studying this material, without spending billions of dollars collecting it,” says Kramers.
The South African researchers said that an international collaborative research program has been formed to continue studies of the Hypatia stone.
“Comets contain the very secrets to unlocking the formation of our solar system and this discovery gives us an unprecedented opportunity to study comet material first hand,” said Block.
The first scoop of Martian soil analyzed by Curiosity Rover’s built-in laboratory has revealed a high amount of water in the soil, according to NASA.
“One of the most exciting results from this very first solid sample ingested by Curiosity is the high percentage of water in the soil,” said Curiosity researcher Laurie Leshin, of the Rensselaer Polytechnic Institute. “About 2 percent of the soil on the surface of Mars is made up of water, which is a great resource, and interesting scientifically.”
Researchers made their findings using Curiosity’s Sample Analysis at Mars (SAM) unit, which includes three sophisticated instruments: a gas chromotograph, mass spectrometer, and tunable laser spectrometer.
SAM allowed the scientists to identify a wide range of chemical compounds and to calculate the ratios of different isotopes of the sample’s key elements.
The same soil sample, when heated to 835 degrees Celsius, showed significant amounts of carbon dioxide, oxygen and various sulfur compounds.
The heated collection of Martian dust, dirt and fine soil, gathered by the rover’s scoop at a location called Rocknest, also revealed a compound containing chlorine and oxygen, which the scientists think is likely chlorate or perchlorate.
Up until this finding, the scientists had thought those materials only existed in the high-latitude areas of Mars. By finding them at Curiosity’s current location near the equator of Mars, the researchers say that perhaps they could be found all over the planet.
Since they are formed in the presence of water, the carbonate materials that were found in their tested sample, according to the researchers, also provided clues to Martian water.
According to Leshin, the results of her team’s research shed light on the composition of the planet’s surface, while offering direction for future research.
“We now know there should be abundant, easily accessible water on Mars,” said Leshin. “When we send people, they could scoop up the soil anywhere on the surface, heat it just a bit, and obtain water.”