Apr 13, 2013
Compact Multipurpose Scooter for Crowded Megacities
TUM CREATE has unveiled an all-new multipurpose scooter prototype, codenamed VOI, at the 3rd Taiwan International Electric Vehicle Show (EV Taiwan). VOI gets its name from the Vietnamese word for elephant -- a symbol of a safe and intelligent mean of transport. It is a two-wheel concept vehicle jointly developed by students from Technische Universität Muenchen (TUM) and Singapore's Nanyang Technological University (NTU), and was built in Singapore.
The design brief for the VOI was to develop a two-wheel transporter that is as agile and affordable as a scooter and, at the same time, as safe and comfortable as a car. With its compact size and maneuverability, the two-wheel electric scooter is designed as a transporter for densely populated megacities and offers a comprehensive solution to metropolises where congested traffic is a major problem.
Positioning the rider behind allows for a compact design and the use of an enclosed passenger cabin that shields occupants from the elements. The enclosure also offers added rigidity and stiffness to the vehicle chassis, which provides additional passenger protection.
With the VOI, business people are able to commute quickly, comfortably and safely through the gridlocks to rush from one meeting to another. It can also address the 'First/Last Mile Problem', where it complements an existing metro railway and public transport system, to offer commuters intermediate transportation between the stations to their destinations.
Furthermore, the VOI is not just limited to transporting passengers. Its modular front pod can be swapped for a cargo box or even a mobile kitchen -- making it a multipurpose vehicle. It is not only a more efficient mode of transport; it also reduces pollution within a metropolis with zero tailpipe emissions. Thanks to its lightweight design, the VOI is capable of reaching a nominal range of 80 km and has a maximum speed of 45 km/h.
Read more at Science Daily
Secrets of Bacterial Slime Revealed
Newcastle University scientists have revealed the mechanism that causes a slime to form, making bacteria hard to shift and resistant to antibiotics.
When under threat, some bacteria can shield themselves in a slimy protective layer, known as a biofilm. It is made up of communities of bacteria held together to protect themselves from attack.
Biofilms cause dental plaque and sinusitis; in healthcare, biofilms can lead to life threatening and difficult to treat infections, particularly on medical implants such as catheters, heart valves, artificial hips and even breast implants. They also they coat the outside of ships and boats polluting the water.
Publishing in the Journal of Biological Chemistry, the team reveal how a molecular switch regulates biofilm formation. This new understanding could help identify a new target for antibiotics and prevent other biofilms from forming.
In order to thwart them from causing disease and biopollution, a Newcastle University team have been studying at the molecular level how bacteria form biofilms in the first instance.
They reveal how the master regulator of biofilm formation, a protein called SinR, acts in the model bacterium, Bacillus subtilis.
Richard Lewis, Professor of Structural Biology in the Institute for Cell and Molecular Biosciences who led the research said: "SinR is a bit like a rocker switch, a domestic light switch for instance. In the "down" position, when SinR is bound to DNA, the proteins required to make a biofilm are turned off and the bacteria are free to move. In the "up" position, SinR is no longer bound to DNA and instead interacts with other proteins, and the biofilms genes are turned on."
SinR is a DNA-binding protein that acts to inhibit the expression of proteins required for the synthesis of the molecular glue that holds the biofilm together. The ability of SinR to bind to DNA is carefully controlled by a network of interactions with three other proteins. By the application of X-ray crystallography, the team have determined precisely how SinR interacts with very specific feature of its DNA target.
Read more at Science Daily
When under threat, some bacteria can shield themselves in a slimy protective layer, known as a biofilm. It is made up of communities of bacteria held together to protect themselves from attack.
Biofilms cause dental plaque and sinusitis; in healthcare, biofilms can lead to life threatening and difficult to treat infections, particularly on medical implants such as catheters, heart valves, artificial hips and even breast implants. They also they coat the outside of ships and boats polluting the water.
Publishing in the Journal of Biological Chemistry, the team reveal how a molecular switch regulates biofilm formation. This new understanding could help identify a new target for antibiotics and prevent other biofilms from forming.
In order to thwart them from causing disease and biopollution, a Newcastle University team have been studying at the molecular level how bacteria form biofilms in the first instance.
They reveal how the master regulator of biofilm formation, a protein called SinR, acts in the model bacterium, Bacillus subtilis.
Richard Lewis, Professor of Structural Biology in the Institute for Cell and Molecular Biosciences who led the research said: "SinR is a bit like a rocker switch, a domestic light switch for instance. In the "down" position, when SinR is bound to DNA, the proteins required to make a biofilm are turned off and the bacteria are free to move. In the "up" position, SinR is no longer bound to DNA and instead interacts with other proteins, and the biofilms genes are turned on."
SinR is a DNA-binding protein that acts to inhibit the expression of proteins required for the synthesis of the molecular glue that holds the biofilm together. The ability of SinR to bind to DNA is carefully controlled by a network of interactions with three other proteins. By the application of X-ray crystallography, the team have determined precisely how SinR interacts with very specific feature of its DNA target.
Read more at Science Daily
Apr 12, 2013
Are Human Genes Patentable?
On April 15, the Supreme Court of the United States will hear oral argument in Association for Molecular Pathology v. Myriad Genetics, a case that could answer the question, "Under what conditions, if any, are isolated human genes patentable?" Kevin Emerson Collins, JD, patent law expert and professor of law at Washington University in St. Louis, believes that layered uncertainties make this case an unusually difficult case in which to predict the outcome.
During the early 1990s, Myriad Genetics made important scientific discoveries related to mutations in the BRCA 1 and BRCA 2 genes, which are biomarkers for increased risk of breast and ovarian cancer. Based on this work, Myriad sought, and obtained, patent protection for "isolated" DNA molecules that embody these sequences.
The Supreme Court's opinion in Myriad will determine whether Myriad's gene patents are valid or, alternatively, whether they were improperly issued from the beginning.
"The legal controversy centers on patent law's 'products of nature' doctrine -- a doctrine that prevents the patenting of newly made products that do not display a 'marked difference' from naturally occurring products," Collins says.
"A perfectly circular section cut out of a leaf of a newly discovered plant may be technically new at the time that it is first made -- and it may be socially useful if the leaf contains chemicals that are natural wound healers, but it's likely an unpatentable product of nature because there is no marked difference between the newly created product and the naturally occurring product.
"Importantly, the Myriad gene patents only encompass DNA molecules in an 'isolated' state, separate from the remainder of the chromosome in which they exist in a human body, and they thus describe molecules that were technically new when Myriad first made them."
The question before the Court is whether the structural and functional differences between naturally occurring DNA molecules and DNA molecules in an isolated state is sufficiently significant to constitute a "marked difference" and to sanction the patenting of the isolated DNAs.
Behind the legal controversy is an economic controversy that may (or may not) influence the Supreme Court's pronouncement on the products of nature doctrine. "The social costs of the exclusive rights to inventions granted by patents are normally justified by the incentives that patents provide for self-interested entities to invest in research and development and generate the socially valuable inventions," Collins says.
However, under some circumstances, there are legitimate concerns that the incentive-based benefits of patents may not outweigh these costs.
"One function of the products of nature doctrine is to ensure that the basic tools of scientific and technological work are not constrained by claims of patent rights and remain free for all to use as inputs into future research," says Collins.
"To the extent that isolated genes are essential technological and scientific building blocks, the costs of Myriad's gene patents in the form of slower innovation in the future may be so great that they will outweigh the benefits of the patent-induced incentives that speed up the creation of the isolated genes themselves."
The verdict
Collins says it is difficult to predict how the Supreme Court will decide this case because of three compounded uncertainties.
First, the Supreme Court has to date not offered a clear legal framework for identifying products of nature, so it is unclear how high a hurdle the markedly different standard will prove to be.
Second, it is unclear how strongly the Court's legal determination will be influenced by the underlying economic concerns about the privatization of the building blocks of technological progress.
Read more at Science Daily
During the early 1990s, Myriad Genetics made important scientific discoveries related to mutations in the BRCA 1 and BRCA 2 genes, which are biomarkers for increased risk of breast and ovarian cancer. Based on this work, Myriad sought, and obtained, patent protection for "isolated" DNA molecules that embody these sequences.
The Supreme Court's opinion in Myriad will determine whether Myriad's gene patents are valid or, alternatively, whether they were improperly issued from the beginning.
"The legal controversy centers on patent law's 'products of nature' doctrine -- a doctrine that prevents the patenting of newly made products that do not display a 'marked difference' from naturally occurring products," Collins says.
"A perfectly circular section cut out of a leaf of a newly discovered plant may be technically new at the time that it is first made -- and it may be socially useful if the leaf contains chemicals that are natural wound healers, but it's likely an unpatentable product of nature because there is no marked difference between the newly created product and the naturally occurring product.
"Importantly, the Myriad gene patents only encompass DNA molecules in an 'isolated' state, separate from the remainder of the chromosome in which they exist in a human body, and they thus describe molecules that were technically new when Myriad first made them."
The question before the Court is whether the structural and functional differences between naturally occurring DNA molecules and DNA molecules in an isolated state is sufficiently significant to constitute a "marked difference" and to sanction the patenting of the isolated DNAs.
Behind the legal controversy is an economic controversy that may (or may not) influence the Supreme Court's pronouncement on the products of nature doctrine. "The social costs of the exclusive rights to inventions granted by patents are normally justified by the incentives that patents provide for self-interested entities to invest in research and development and generate the socially valuable inventions," Collins says.
However, under some circumstances, there are legitimate concerns that the incentive-based benefits of patents may not outweigh these costs.
"One function of the products of nature doctrine is to ensure that the basic tools of scientific and technological work are not constrained by claims of patent rights and remain free for all to use as inputs into future research," says Collins.
"To the extent that isolated genes are essential technological and scientific building blocks, the costs of Myriad's gene patents in the form of slower innovation in the future may be so great that they will outweigh the benefits of the patent-induced incentives that speed up the creation of the isolated genes themselves."
The verdict
Collins says it is difficult to predict how the Supreme Court will decide this case because of three compounded uncertainties.
First, the Supreme Court has to date not offered a clear legal framework for identifying products of nature, so it is unclear how high a hurdle the markedly different standard will prove to be.
Second, it is unclear how strongly the Court's legal determination will be influenced by the underlying economic concerns about the privatization of the building blocks of technological progress.
Read more at Science Daily
Alternative Way to Explain Life's Complexity Proposed
Instead of starting from simpler precursors and becoming more intricate, say authors Dan McShea and Wim Hordijk, some structures could have evolved from complex beginnings that gradually grew simpler -- an idea they dub "complexity by subtraction." Computer models and trends in skull evolution back them up, the researchers show in a study published this week in the journal Evolutionary Biology.
Some biological structures are too dizzyingly complex to have emerged stepwise by adding one part and then the next over time, intelligent design advocates say. Consider the human eye, or the cascade that causes blood to clot, or the flagellum, the tiny appendage that enables some bacteria to get around. Such all-or-none structures, the argument goes, need all their parts in order to function. Alter or take away any one piece, and the whole system stops working. In other words, what good is two thirds of an eye, or half of a flagellum?
For the majority of scientists, the standard response is to point to simpler versions of supposedly 'irreducibly complex' structures that exist in nature today, such as cup eyes in flatworms. Others show how such structures could have evolved incrementally over millions of years from simpler precursors. A simple eye-like structure -- say, a patch of light-sensitive cells on the surface of the skin -- could evolve into a camera-like eye like what we humans and many other animals have today, biologists say.
"Even a very simple eye with a small number of parts would work a little. It would be able to detect shadows, or where light is coming from," said co-author Dan McShea of Duke University.
In a new study, McShea and co-author Wim Hordijk propose an alternative route. Instead of emerging by gradually and incrementally adding new genes, cells, tissues or organs over time, what if some so-called 'irreducibly complex' structures came to be by gradually losing parts, becoming simpler and more streamlined? Think of naturally occurring rock arches, which start as cliffs or piles of stone and form when bits of stone are weathered away. They call the principle 'complexity by subtraction.'
"Instead of building up bit by bit from simple to complex, you start complex and then winnow out the unnecessary parts, refining them and making them more efficient as you go," McShea said.
A computer model used by co-author Wim Hordijk supports the idea. In the model, complex structures are represented by an array of cells, some white and some black, like the squares of a checkerboard. In this class of models known as cellular automata, the cells can change between black and white according to a set of rules.
Using a computer program that mimics the process of inheritance, mutation, recombination, and reproduction, the cells were then asked to perform a certain task. The better they were at accomplishing the task, the more likely they were to get passed on to the next generation, and over time a new generation of rules replaced the old ones. In the beginning, the patterns of black and white cells that emerged were quite complex. But after several more generations, some rules 'evolved' to generate simpler black and white cell patterns, and became more efficient at performing the task, Hordijk said.
We see similar trends in nature too, the authors say. Summarizing the results of previous paleontological studies, they show that vertebrate skulls started out complex, but have grown simpler and more streamlined. "For example, the skulls of fossil fish consist of a large number of differently-shaped bones that cover the skull like a jigsaw puzzle," McShea said. "We see a reduction in the number of skull bone types in the evolutionary transitions from fish to amphibian to reptile to mammal." In some cases skull bones were lost; in other cases adjacent bones were fused. Human skulls, for example, have fewer bones than fish skulls.
Read more at Science Daily
10 Unbelievable Dinos That Really Existed
Dome-Headed Dinos
Dinosaurs by their nature seem bizarre, larger than life -- mysterious. And the history of dinos is constantly rewritten. Here we present to you 10 dinos that are furrier, freakier and more colorful than we previously thought possible.
Dome-Headed Dinos
Head-butting pachycephalosaurs, with noggins shaped like built-in football helmets, have long puzzled paleontologists.
"The head-slapping behavior of crocodiles and the face-pecking observed in a variety of birds suggest that 'using your head' is not unique to pachycephalosaurs," says Joseph Peterson, a geology professor at the University of Wisconsin. "Domes likely evolved in response to such behavior."
Four-Winged Dino
Scientists now think that some dinos that flew didn't have two wings. They had four.
"The first birds descended from four-winged dinosaurs," says renowned dinosaur and early avian hunter Xing Xu, a professor at the Chinese Academy of Sciences. One such dinosaur might have been Microraptor, a non-avian dino that had feathers on both its arms and legs.
Dinochicken
OK, full disclosure: This dino doesn't exist yet. But even conceptually it's bizarre enough to be included in this list. It's a dino -- and it's a chicken. It's a Dinochicken.
Paleontologist Jack Horner and his colleagues have been genetically engineering chickens to reactivate ancestral traits, such as long tails, which are more associated with non-avian dinosaurs.
"Birds are dinosaurs," Horner told Discovery News. "So technically we're making a dinosaur out of a dinosaur."
Read more at Discovery News
Dome-Headed Dinos
Head-butting pachycephalosaurs, with noggins shaped like built-in football helmets, have long puzzled paleontologists.
"The head-slapping behavior of crocodiles and the face-pecking observed in a variety of birds suggest that 'using your head' is not unique to pachycephalosaurs," says Joseph Peterson, a geology professor at the University of Wisconsin. "Domes likely evolved in response to such behavior."
Four-Winged Dino
"The first birds descended from four-winged dinosaurs," says renowned dinosaur and early avian hunter Xing Xu, a professor at the Chinese Academy of Sciences. One such dinosaur might have been Microraptor, a non-avian dino that had feathers on both its arms and legs.
Dinochicken
Paleontologist Jack Horner and his colleagues have been genetically engineering chickens to reactivate ancestral traits, such as long tails, which are more associated with non-avian dinosaurs.
"Birds are dinosaurs," Horner told Discovery News. "So technically we're making a dinosaur out of a dinosaur."
Read more at Discovery News
Stone Mystery in Sea of Galilee
A giant "monumental" stone structure discovered beneath the waters of the Sea of Galilee in Israel has archaeologists puzzled as to its purpose and even how long ago it was built.
The mysterious structure is cone shaped, made of "unhewn basalt cobbles and boulders," and weighs an estimated 60,000 tons the researchers said. That makes it heavier than most modern-day warships.
Rising nearly 32 feet (10 meters) high, it has a diameter of about 230 feet (70 meters). To put that in perspective, the outer stone circle of Stonehenge has a diameter just half that with its tallest stones not reaching that height.
It appears to be a giant cairn, rocks piled on top of each other. Structures like this are known from elsewhere in the world and are sometimes used to mark burials. Researchers do not know if the newly discovered structure was used for this purpose.
The structure was first detected in the summer of 2003 during a sonar survey of the southwest portion of the sea. Divers have since been down to investigate, they write in the latest issue of the International Journal of Nautical Archaeology.
"Close inspection by scuba diving revealed that the structure is made of basalt boulders up to 1 m (3.2 feet) long with no apparent construction pattern," the researchers write in their journal article. "The boulders have natural faces with no signs of cutting or chiselling. Similarly, we did not find any sign of arrangement or walls that delineate this structure."
They say it is definitely human-made and probably was built on land, only later to be covered by the Sea of Galilee as the water level rose. "The shape and composition of the submerged structure does not resemble any natural feature. We therefore conclude that it is man-made and might be termed a cairn," the researchers write.
More than 4,000 years old?
Underwater archaeological excavation is needed so scientists can find associated artifacts and determine the structure's date and purpose, the researchers said.
Researcher Yitzhak Paz, of the Israel Antiquities Authority and Ben-Gurion University, believes it could date back more than 4,000 years. "The more logical possibility is that it belongs to the third millennium B.C., because there are other megalithic phenomena [from that time] that are found close by," Paz told LiveScience in an interview, noting that those sites are associated with fortified settlements.
The researchers list several examples of megalithic structures found close to the Sea of Galilee that are more than 4,000 years-old. One example is the monumental site of Khirbet Beteiha, located some 19 miles (30 kilometers) north-east of the submerged stone structure, the researchers write. It "comprises three concentric stone circles, the largest of which is 56 m (184 feet) in diameter."
If the third-millennium B.C. date idea proves correct it would put the structure about a mile to the north of a city that researchers call "Bet Yerah" or "Khirbet Kerak."
During the third millennium B.C. the city was one of the biggest sites in the region, Paz said. "It's the most powerful and fortified town in this region and, as a matter of fact, in the whole of Israel."
Archaeologist Raphael Greenberg describes it in a chapter of the book "Daily Life, Materiality, and Complexity in Early Urban Communities of the Southern Levant" (Eisenbrauns, 2011) as being a heavily fortified 74-acre (30 hectares) site with up to 5,000 inhabitants.
With paved streets and towering defenses its people were clearly well organized. "They also indicate the existence of some kind of municipal authority able to maintain public structures ..." Greenberg writes.
The research team says that, like the leaders of Bet Yerah, whoever built the newly discovered Sea of Galilee structure needed sophisticated organization and planning skills to construct it. The "effort invested in such an enterprise is indicative of a complex, well-organized society, with planning skills and economic ability," they write in their journal paper.
Paz added that "in order to build such a structure a lot of working hours were required" in an organized community effort.
Read more at Discovery News
Apr 11, 2013
Fossilized Teeth Provide New Insight Into Human Ancestor: Species Identified in 2010 Is One of Closest Relatives to Humans
A dental study of fossilized remains found in South Africa in 2008 provides new support that this species is one of the closest relatives to early humans.
The teeth of this species -- called Australopithecus sediba -- indicate that it is also a close relative to the previously identified Australopithecus africanus. Both of these species are clearly more closely related to humans than other australopiths from east Africa, according to the new research.
The study, published in the journal Science, revealed that both africanus and sediba shared about the same number of dental traits with the first undeniably human species.
"Our study provides further evidence that sediba is indeed a very close relative of early humans, but we can't definitively determine its position relative to africanus, said Debbie Guatelli-Steinberg, co-author of the study and professor of anthropology at The Ohio State University.
The research was led by Joel D. Irish, professor of natural sciences at Liverpool John Moores University.
The sediba fossils were found in South Africa in 2008 and first described in a series of articles published in Science in 2010. That study was led by Lee Berger of the University of Witwatersrand in South Africa, who is also a co-author of this new study.
In this study, Irish, Guatelli-Steinberg and their colleagues extended that work by examining the teeth from sediba and comparing them to eight other African hominin species, which include modern humans from Africa, and extinct species of Homo, Australopithecus, and Paranthropus. In all, the researchers examined more than 340 fossils and 4,571 recent specimens. They also examined teeth from 44 gorillas for comparison.
The focus was on 22 separate traits of tooth crowns and roots that can give clues as to the relationship between the different species studied.
For example, they measured how much one of the incisors was shovel-shaped. Depending on the species in this study, the incisor may have no depression in the back of the tooth, a faint shovel shape, or a trace of that shape.
Researchers use standardized measurements from the Arizona State University Dental Anthropology System to compare the teeth on these 22 traits.
The researchers found that on 15 of these traits, sediba and africanus scored the same. Sediba shared 13 traits with Homo erectus, an early human species, which was comparable to how africanus scored.
Sediba and africanus shared five dental traits that weren't found in earlier australopiths, further showing their close relationship. Both also share five traits with early humans -- Homo habilis/rudolfenis and Homo erectus -- which weren't shared with earlier ancestors, demonstrating the close relationship between these two australopiths and the first humans.
Teeth are an excellent way to study relationships between different species, Guatelli-Steinberg said. They are well preserved in the fossil record, and researchers can compare large samples, at least for many ancient species.
In addition, most of the dental traits the researchers used in this analysis don't have a selective advantage that could help one species survive over another. That means if researchers see a similar trait in two species, they can be more confident that they shared a common ancestor and that the trait didn't evolve independently.
In many ways, these new dental data support the earlier research on sediba, which included analysis of the inside of the skull, hand, spine, pelvis, foot and ankle, Guatelli-Steinberg said.
"All of the research so far shows that sediba had a mosaic of primitive traits and newer traits that suggest it was a bridge between earlier australopiths and the first humans," she said.
Guatelli-Steinberg said their dental analysis showed that both africanus and sediba are more closely related to humans than the famous "Lucy" skeleton fossil found in East Africa in 1974. This fossil represented a species, Australopithecus afarensis, that was at one time was thought to be the closest relative of humans.
Lucy is estimated to have lived 3.2 million years ago. Sediba lived 1.977 million years ago, while africanus lived between 3.03 and 2.04 million years ago.
Read more at Science Daily
The teeth of this species -- called Australopithecus sediba -- indicate that it is also a close relative to the previously identified Australopithecus africanus. Both of these species are clearly more closely related to humans than other australopiths from east Africa, according to the new research.
The study, published in the journal Science, revealed that both africanus and sediba shared about the same number of dental traits with the first undeniably human species.
"Our study provides further evidence that sediba is indeed a very close relative of early humans, but we can't definitively determine its position relative to africanus, said Debbie Guatelli-Steinberg, co-author of the study and professor of anthropology at The Ohio State University.
The research was led by Joel D. Irish, professor of natural sciences at Liverpool John Moores University.
The sediba fossils were found in South Africa in 2008 and first described in a series of articles published in Science in 2010. That study was led by Lee Berger of the University of Witwatersrand in South Africa, who is also a co-author of this new study.
In this study, Irish, Guatelli-Steinberg and their colleagues extended that work by examining the teeth from sediba and comparing them to eight other African hominin species, which include modern humans from Africa, and extinct species of Homo, Australopithecus, and Paranthropus. In all, the researchers examined more than 340 fossils and 4,571 recent specimens. They also examined teeth from 44 gorillas for comparison.
The focus was on 22 separate traits of tooth crowns and roots that can give clues as to the relationship between the different species studied.
For example, they measured how much one of the incisors was shovel-shaped. Depending on the species in this study, the incisor may have no depression in the back of the tooth, a faint shovel shape, or a trace of that shape.
Researchers use standardized measurements from the Arizona State University Dental Anthropology System to compare the teeth on these 22 traits.
The researchers found that on 15 of these traits, sediba and africanus scored the same. Sediba shared 13 traits with Homo erectus, an early human species, which was comparable to how africanus scored.
Sediba and africanus shared five dental traits that weren't found in earlier australopiths, further showing their close relationship. Both also share five traits with early humans -- Homo habilis/rudolfenis and Homo erectus -- which weren't shared with earlier ancestors, demonstrating the close relationship between these two australopiths and the first humans.
Teeth are an excellent way to study relationships between different species, Guatelli-Steinberg said. They are well preserved in the fossil record, and researchers can compare large samples, at least for many ancient species.
In addition, most of the dental traits the researchers used in this analysis don't have a selective advantage that could help one species survive over another. That means if researchers see a similar trait in two species, they can be more confident that they shared a common ancestor and that the trait didn't evolve independently.
In many ways, these new dental data support the earlier research on sediba, which included analysis of the inside of the skull, hand, spine, pelvis, foot and ankle, Guatelli-Steinberg said.
"All of the research so far shows that sediba had a mosaic of primitive traits and newer traits that suggest it was a bridge between earlier australopiths and the first humans," she said.
Guatelli-Steinberg said their dental analysis showed that both africanus and sediba are more closely related to humans than the famous "Lucy" skeleton fossil found in East Africa in 1974. This fossil represented a species, Australopithecus afarensis, that was at one time was thought to be the closest relative of humans.
Lucy is estimated to have lived 3.2 million years ago. Sediba lived 1.977 million years ago, while africanus lived between 3.03 and 2.04 million years ago.
Read more at Science Daily
Secret Population of Orangutans Found
All subspecies of Bornean orangutans are listed as endangered by the International Union for Conservation of Nature. But scientists estimate just 3,000 to 4,500 individuals are left in the subspecies known as Pongo pygmaeus pygmaeus, making them the most severely threatened.
Two-thousand of those live in the Malaysian state of Sarawak in Batang Ai National Park and Lanjak-Entimau Wildlife Sanctuary, researchers say. The previously unknown population was found by conservationists near the Batang park, in an area covering about 54 square miles (140 square kilometers).
Local communities apparently had been aware of the apes, but no major research projects had been undertaken in the area until February, when conservations with WCS and other groups surveyed the region. They found a total of 995 orangutan nests, including fresh nests that indicated the rare population was recently using the area.
Previously, researchers studying fresh nests left by wild orangutans in Indonesia found they are incredibly complex, made in the crooks of large branches. The orangutans bend and interweave living branches about an inch (3 centimeters) wide to form the nest.
"They are just bent. They can actually stay living and later on you can go back to them and see they are like an archeological artifact of all these strangely bent items," said Roland Ennos of the University of Manchester, in the United Kingdom, when the study was published last year in the journal Proceedings of the National Academy of Sciences. "It's very similar to weaving a basket, they have to break the branches, weave them together and form a nice, strong, rigid structure."
Read more at Discovery News
Think the Planet Isn't Warming? Check the Ocean
Except that … it wasn’t.
As The Economist piece itself pointed out, this wasn’t an argument that “global warming has ‘stopped.‘” The past two decades have been the hottest in recorded history; of the nine hottest years on record, eight have come since 2000. The question, though, is why the year-on-year/decade-on-decade increase appears to have been somewhat less in the past 10 to 15 years, given the ongoing increase in atmospheric greenhouse gas concentrations.
To which there are several answers.
First, the smaller the temporal time scale, the more the short-term fluctuations, forcings and feedbacks — from aerosol emissions to La Niña events — can distort the bigger picture. Over a longer scale, the evidence is increasing that the rate of warming is probably unprecedented in over 11,000 years.
Second, The Economist article, and the skeptic narrative that has absorbed it, focuses on what is known as “climate sensitivity,” which is how much surface warming the planet will experience in response to a doubling of atmospheric carbon dioxide concentrations relative to pre-Industrial Revolution levels. (Those pre-industrial levels were approximately 280 ppm; a doubling therefore would be roughly 560 ppm. Present levels are closing in on 397 ppm.)
But, as climate blogger Joe Romm points out, climate sensitivity is but one factor in determining how much the planet will warm in the future; another hugely important one is the extent to which CO2 concentrations will actually increase, and present trends suggest they will blow past 560 ppm and wind up closer to 1,000 ppm. Additionally, while climate sensitivity estimates are greatly influenced by short-term feedbacks such as sea ice extent and water vapor, they do not factor in “slow” feedbacks, such as the release of methane as a result of tundra melt. Nor do they consider the non-linearity of such feedbacks – i.e. the fact that they may become significant relatively suddenly.
Third, the data referred to by The Economist suggest that climate sensitivity may be at the very low end of projected estimates of between 2 degrees Celsius and 4.5 degrees Celsius. If that indeed does prove to be the case, then that’s obviously good news. But, as Zeke Hausfather pointed out in a post at the Yale Forum on Climate Change and the Media: “A world with a relatively low climate sensitivity — say in the range of 2 °C — but with high emissions and with atmospheric concentrations three to four times those of pre-industrial levels is still probably a far different planet than the one we humans have become accustomed to. And it’s likely not one we would find nearly so hospitable.”
Finally, and most importantly, there is plenty of reason to suspect that climate sensitivity isn’t lower than expected; because, critically, discussions of climate sensitivity tend to focus on surface warming of the planet; but several recent studies have shown that in fact an increasing amount of warming is taking place beneath the surface, in the ocean depths.
Ninety percent of warming goes into heating, not the land or the atmosphere, but the ocean; two recent papers, in 2012 and earlier this year, showed that approximately 30 percent of recent ocean warming has been taken up by waters below depths of 700 meters (about 2,300 feet), where few measurements had previously taken place. That was reinforced by a European study, published earlier this week, which, according to Reuters, found “that the oceans took up more warmth from the air around 2000. That would help explain the slowdown in surface warming but would also suggest that the pause may be only temporary and brief … Lead author Virginie Guemas of the Catalan Institute of Climate Sciences in Barcelona said the hidden heat may return to the atmosphere in the next decade, stoking warming again.”
Read more at Discovery News
Half-Human, Half-Ape Ancestor Reconstructed
The species, Australopithecus sediba, is a striking example of human evolution, conclude six papers published in the journal Science. Taken together, the papers describe how Au. sediba looked, walked, chewed and moved.
"Sediba shows a strange mix of primitive australopithecine traits and derived Homo traits -- face and anterior dentition like Homo, shape of the cranium like Homo, other parts of the face and size of the cranium like an australopithecine, arms like an australopithecine, pelvis and lower limbs like Homo and feet and ankles like an australopithecine," project leader Lee Berger told Discovery News.
"It does look like a good 'transitional' fossil, doesn't it?" added Berger, who is a researcher in the Wits Evolutionary Studies Institute at the University of the Witwatersrand. He named the species, which was found at a site called Malapa, near Johannesburg.
The tooth study found that Au. sediba was closely related to Au. africanus, which lived until about 2.1 million years ago. These species, in turn, shared numerous dental similarities with Homo erectus, an early human species.
"All of the research so far shows that sediba had a mosaic of primitive traits and newer traits that suggest it was a bridge between earlier australopiths and the first humans," said Debbie Guatelli-Steinberg, co-author of one of the studies and a professor of anthropology at Ohio State University.
Prior research determined what Au. sediba ate.
Peter Schmid of the University of Zurich, who also analyzed this species' remains, shared that the early probable ancestor was not a carnivore.
"Microscopic elements of plants were found in the tartar of the teeth of Au. sediba," Schmid told Discovery News. "It was largely a vegetarian and shows a rather human-like chewing apparatus."
In terms of how it walked, Schmid and the other researchers explained that Au. sediba had a small heel resembling that of a chimp. It walked rather awkwardly -- with an inward rotation of the knee and hip, with its feet slightly twisted. The scientists conclude that this pigeon-toed way of walking on two limbs might have been an evolutionary compromise between walking upright and tree climbing.
Such a detailed understanding of these movements is possible because remains for a female Au. sediba preserve her heel, ankle, knee, hip and lower back. In contrast, the famous "Lucy" skeleton, representative of the species Au. afarensis, only preserves a hip and ankle.
Yet another new study analyzed Au. sediba's upper limbs. They were "primitive," meaning more like those of an ape, suggesting that these individuals still spent some time swinging and climbing in trees.
This again makes Au. sediba a good candidate as a transitional species, because it appears to have spent most of its time on the ground, but it hadn't entirely left the trees yet.
"The terrestrial adaptation was much more evolved, but there are indications that it had still a large part of climbing in its locomotor spectrum," Schmid explained.
Read more at Discovery News
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