Direct Neural Interfacing for Robotics

Out of Tropics: Species Originate in Tropics and Spread

Although scientists have known since the middle of the 19th century that the tropics are teeming with species while the poles harbor relatively few, the origin of the most dramatic and pervasive biodiversity on Earth has never been clear.

New research sheds light on how that pattern came about. Furthermore, it confirms that the tropics have been and continue to be the Earth's engine of biodiversity.

By examining marine bivalves (two-shelled mollusks including scallops, cockles and oysters), a model system for large-scale ecological and evolutionary analysis, the study shows that most evolutionary lineages started in the tropics and expanded outward.

"This 'out of the tropics' dynamic is the major process that shapes the latitudinal pattern of biodiversity that we see today on land and sea," said lead author David Jablonski, the William R. Kenan Jr. Professor in Geophysical Sciences at the University of Chicago. His team focuses on marine bivalves because they combine a wealth of important biological patterns with a large but manageable number of living species (about 8,000) and a rich fossil record.

The new research will be published this week in the online Early Edition of the Proceedings of the National Academy of Sciences presents evidence that the "out of the tropics" process is driven mainly by bridge species, a new term referring to evolutionary lineages that straddle the boundary between the tropics and cooler neighboring regions.

"We thought the 'out of the tropics' process would be driven by the formation of new species at the edge of the tropics, but that doesn't seem to be true," Jablonski said. "Whether bridge species really are the conduit, 'out of the tropics' for all those lineages still needs to be confirmed. We'll tackle that next, by examining molecular data on species within these lineages, inside and outside the tropics, to see how they're related."

As with the PNAS study, this follow-up research would require examining data on both fossils and living organisms. "Alas, it's still rare for paleontologists to integrate the fossil record with data on present-day organisms, but for large-scale biodiversity studies like this, it's a very powerful approach, often an essential one," Jablonski said. "Biodiversity is a product of origination, extinction and immigration, and when the fossil record is adequate, as it is with bivalves, it provides the most robust window into the dynamics that produced present-day patterns."

Edicaran Aspidella Acts Like a Cnidarian

Evidence for Cnidaria-like behavior in ca. 560 Ma Ediacaran Aspidella

Authors:

1. Latha R. Menon (a)
2. Duncan McIlroy (b)
3. Martin D. Brasier (a,b)

Affiliations:

a. Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK

b. Department of Earth Sciences, Memorial University of Newfoundland, St John's, Newfoundland A1B 3X5, Canada

Abstract:

The first appearance of animals in the geological record is a matter of continuing debate: how deep were the roots of the Cambrian explosion? Molecular clock estimates indicate that the deepest divergences of the Metazoa had occurred by the Ediacaran Period (635–541 Ma), yet evidence of animal activity from well below the Ediacaran-Cambrian boundary has been rare and often questionable. Meanwhile, the Ediacaran macrobiota has remained enigmatic, as emphasized by recent controversial claims that South Australia Ediacaran forms were not marine animals at all, but land-based lichens and microbial colonies. Here we report evidence for animal-like behavior in a submerged setting in a key Ediacaran form, Aspidella terranovica Billings 1872, a discoidal fossil from the ca. 560 Ma Fermeuse Formation of Newfoundland (Canada). We describe sedimentary fabrics indicating progressive vertical movement of an organism through sediment in response to an aggrading sediment-water interface. Such equilibrium traces are familiar from the Phanerozoic and are observed in partially buried marine animals such as tube anemones today. Furthermore, horizontal trails closely comparable to trails previously described from ∼565 m.y. old Mistaken Point (Newfoundland) are now linked to Aspidella. Our findings constitute evidence of both vertical and horizontal movement in a key Ediacaran taxon, consistent with an animal of cnidarian grade. Moreover, because Aspidella is also reported from the Rawnsley Quartzite of South Australia, our evidence conflicts with the proposed radical interpretation of that Ediacaran fossil assemblage. We demonstrate that at least some Ediacaran forms were probably early animals, and that they lived underwater.

Turkey's Indigenous Stealth Fighter Program

Turkey's aviation industry has come a long way since it began building F-16 Fighting Falcons in the 1980s. Now it is confident that it can produce an aircraft in-country that will not only replace the F-16 but complement the F-35 Joint Strike Fighter in years to come.

Turkish Aviation Industries (TAI) has been working quietly on ideas for a fifth-generation fighter, dubbed the F-X, for several years, but 2013 represents a critical year in the decision-making process for the project. A $20 million two-year concept phase, started in August 2011, will end this September, and a meeting of Turkey's Defense Industry Executive Committee, which takes place at year-end, will define how the program will begin to take shape.

At the IDEF defense show in Istanbul last month, TAI displayed three potential single-seat design concepts for the aircraft: two conventional monoplane layouts, one with a single engine, not dissimilar to the F-35, and one with two engines, while the third featured canard foreplanes and a large delta wing. Each of the concepts features elements of design associated with fifth-generation fighter aircraft, such as faceted fuselages to reduce radar cross-section, internal weapons bays, super-cruise capability as well as advanced avionics and an active, electronically scanned array (AESA) radar system. Engineers have received input from Saab, which was drafted to consult on the program.

TAI officials suggest that the two single-engine concepts will have maximum takeoff weights (MTOW) of 50,000-60,000 lb., while the twin-engine version will have an MTOW of 60,000-70,000 lb. Diagrammatic drawings of the twin-engine aircraft show two weapons bays, one located between the air intakes that can house a pair of small short-range air-to-air missiles, and the other in front of the engines housing four larger missiles around the size of the AIM-120 Amraam.

According to industry officials, the requirements defined by the Turkish air force have changed at least three times, with the specification narrowing to what TAI and Turkish industry will be able to achieve in the coming years. Of the designs shown at IDEF, the twin-engine concept meets the requirements set by the air force, say industry officials, but the service prefers a single-engine aircraft to reduce cost and complexity. Although envisaged as a multirole fighter, TAI officials say the air force may give the resulting aircraft more of an air-to-air/air-dominance role as a primary mission.

Under the current timetable, Turkey will develop the aircraft at the same time as it is paying for the F-35. TAI wants to achieve a first flight for the F-X within 10 years. While the F-35 is set to replace the F-4 Phantoms and early F-16s in the air force inventory, the service sees the F-X replacing later models of the F-16 fleet purchased through various iterations of the Peace Onyx program. The last F-16 produced by TAI was delivered to the air force in December as part of the Peace Onyx IV program.

 

Is This the Design for China's Stealth Bomber?

Click the title link for more.

Was South China Once a Part of India (Geologically Speaking)?

Locating South China in Rodinia and Gondwana: A fragment of greater India lithosphere?

Authors:

1. Peter A. Cawood (a,b)
2. Yuejun Wang (c)
3. Yajun Xu (d)
4. Guochun Zhao (e)

Affiliations:

a. Department of Earth Sciences, University of St Andrews, North Street, St Andrews KY16 9AL, UK

b. Centre for Exploration Targeting, School of Earth and Environment, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia

c. State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China

d. State Key Laboratory of Biogeology and Environmental Geology, Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China

e. Department of Earth Sciences, University of Hong Kong, Pokfulam Road, Hong Kong, China

Abstract:

From the formation of Rodinia at the end of the Mesoproterozoic to the commencement of Pangea breakup at the end of the Paleozoic, the South China craton first formed and then occupied a position adjacent to Western Australia and northern India. Early Neoproterozoic suprasubduction zone magmatic arc-backarc assemblages in the craton range in age from ca. 1000 Ma to 820 Ma and display a sequential northwest decrease in age. These relations suggest formation and closure of arc systems through southeast-directed subduction, resulting in progressive northwestward accretion onto the periphery of an already assembled Rodinia. Siliciclastic units within an early Paleozoic succession that transgresses across the craton were derived from the southeast and include detritus from beyond the current limits of the craton. Detrital zircon age spectra require an East Gondwana source and are very similar to the Tethyan Himalaya and younger Paleozoic successions from Western Australia, suggesting derivation from a common source and by inference accumulation in linked basins along the northern margin of Gondwana, a situation that continued until rifting and breakup of the craton in the late Paleozoic.

Gondwana vs Rodinia: Not All Supercontinents Are Created Equal

Not all supercontinents are created equal: Gondwana-Rodinia case study

Authors:

1. Christopher J. Spencer (a)
2. Chris Hawkesworth (a)
3. Peter A. Cawood (a)
4. Bruno Dhuime (a,b)

Affiliations:

a. Department of Earth and Environmental Sciences, University of St. Andrews, North Street, St. Andrews KY16 9AL, UK

b. Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, UK

Abstract:

The geologic records associated with the formation of the supercontinents Rodinia and Gondwana have markedly different seawater Sr and zircon Hf isotopic signatures. Rodinia-related (Grenville-Sveconorwegian-Sunsas) orogens display significantly less enriched crustal signatures than Gondwana-related (Pan-African) orogens. Seawater Sr isotope ratios also exhibit a more pronounced crustal signal during the span of the Gondwana supercontinent than at the time of Rodinia. Such isotopic differences are attributed to the age and nature of the continental margins involved in the collisional assembly, and specifically to the depleted mantle model ages, and hence the isotope ratios of the material weathered into the oceans. In our preferred model the isotopic signatures of Rodinia-suturing orogens reflect the closure of ocean basins with dual subduction zones verging in opposite directions, analogous to the modern Pacific basin. This would have resulted in the juxtaposition of juvenile continental and island arc terrains on both margins of the colliding plates, thus further reworking juvenile crust. Conversely, the assembly of Gondwana was accomplished primarily via a number of single-sided subduction zones that involved greater reworking of ancient cratonic lithologies within the collisional sutures. The proposed geodynamic models of the assembly of Rodinia and Gondwana provide a connection between the geodynamic configuration of supercontinent assembly and its resulting isotopic signature.

Droids WILL Take Our Jobs, So What Will We Do?

China's CO2 Emission Cuts Allow for Political Games

The new study, published in Proceedings of the National Academy of Sciences (PNAS), provides a detailed consumption-based accounting of carbon dioxide (CO2) emissions in China. Consumption-based accounting allocates emissions to the province where products are ultimately consumed, rather than simply focusing on where emissions occur. It shows that policies to reduce emissions in China may tend to push factories and production into developing regions of the country.

"China has set emissions targets which are more stringent in affluent coastal provinces than in less-developed interior provinces. This may reduce emissions in one region, but in China as a whole, you find CO2 emissions continue to increase, because the polluting factories move into the less-developed regions," says Laixiang Sun, IIASA and University of Maryland researcher who co-authored the study along with an international team including two former participants in IIASA's Young Scientists Summer Program (YSSP). Instead, say the researchers, accounting for carbon emissions based on consumption rather than production could create better incentives and fair distribution of responsibilities to reduce greenhouse gas emissions both nationally and globally.

China is currently the largest emitter of CO2, pumping out 7.2 gigatons of the greenhouse gas every year as of 2007, the year that the study examined. This emission figure shot up to about 10 gigatons in 2011. While the country has pledged to improve their CO2 intensity—the amount of emissions per unit of GDP—Sun says, these efforts may simply encourage provinces to outsource their emissions to poorer regions, placing an unfair and unmanageable burden on those regions.

The same effect occurs on a global scale, as richer countries outsource polluting industries and manufacturing to developing countries—including China—where costs are lower and regulations may be more lax.

"We must reduce CO2 emissions, not just outsource them," says Sun. "Developed regions and countries need to take some responsibility, providing technology support or investment to promote cleaner, greener technology in less-developed regions."

The World Poltiiical Boundaries if We Had Pangea Again

Life gets exciting on many, many fronts.

Please Keep in mind the climate of the time...

hat tip to Randy.

A Bronze Age Megalithic Monument Under the Sea of Galilee?

The shores of the Sea of Galilee, located in the North of Israel, are home to a number of significant archaeological sites. Now researchers from Tel Aviv University have found an ancient structure deep beneath the waves as well.

Researchers stumbled upon a cone-shaped monument, approximately 230 feet in diameter, 39 feet high, and weighing an estimated 60,000 tons, while conducting a geophysical survey on the southern Sea of Galilee, reports Prof. Shmulik Marco of TAU's Department of Geophysics and Planetary Sciences. The team also included TAU Profs. Zvi Ben-Avraham and Moshe Reshef, and TAU alumni Dr. Gideon Tibor of the Oceanographic and Limnological Research Institute.

Initial findings indicate that the structure was built on dry land approximately 6,000 years ago, and later submerged under the water. Prof. Marco calls it an impressive feat, noting that the stones, which comprise the structure, were probably brought from more than a mile away and arranged according to a specific construction plan.

Dr. Yitzhak Paz of the Antiquities Authority and Ben-Gurion University says that the site, which was recently detailed in the International Journal of Nautical Archaeology, resembles early burial sites in Europe and was likely built in the early Bronze Age. He believes that there may be a connection to the nearby ancient city of Beit Yerah, the largest and most fortified city in the area.

A New Reconstruction of the Skull of Archaeopteryx

New observations on the skull of Archaeopteryx

Author:

1. Oliver W. M. Rauhut (a)

Affiliation:

a. Bayerische Staatssammlung fu¨r Pala¨ontologie und Geologie and Department of Earth and Environmental Sciences, LMU Munich, Richard-Wagner-Str. 10, 80333 Munich, Germany

Abstract:

Although skeletal remains of the iconic oldest known avialian Archaeopteryx have been known for almost 150 years, several aspects of the cranial anatomy of this taxon have remained enigmatic, mainly because of the strongly flattened and often fractured and incomplete nature of available skull materials. New investigation of the skulls of the recently described, excellently preserved tenth (Thermopolis) and the seventh (Munich) specimens revealed several previously unrecognized characters and helps to resolve some problematic issues. Thus, the nasal of Archaeopteryx shows a lateral notch for the lacrimal, as is found in many other saurischian dinosaurs, the maxilla clearly participates in the margin of the external nares, and there seems to be a pneumatic foramen in the lacrimal, comparable to the lacrimal fenestra found in many non-avian theropods. In the braincase, Archaeopteryx shows pneumatic features reminiscent of non-avian theropods, including a ventral basisphenoid recess and an anterior tympanic recess that is laterally incised into the basisphenoid/prootic. Most importantly, however, the postorbital process of the jugal shows a facet for the suture with the postorbital, thus resolving the question of whether Archaeopteryx had a closed postorbital bar. A new reconstruction of the skull of Archaeopteryx is presented, making the skull of this taxon even more theropod-like than previously recognized. Furthermore, the closed postorbital bar and the configuration of the bones of the skull roof cast serious doubt on claims that an avian-style cranial kinesis was present in this taxon.

A Nice and Simple Description of the Lagrange (L-x) Points

My Kids at Stinson Beach and a Pale of Jellies

One Take on the Rise of China

Nature and Architecture

Anyone know if the greenhouse project actually went anywhere?

Using Synthetic Biology to Grow Clothes

Reexamining Diandongosaurus acutidentatus, a Chinese Anisian Triassic Eosauropterygian

Diandongosaurus acutidentatus Shang, Wu & Li, 2011 (Diapsida: Sauropterygia) and the relationships of Chinese eosauropterygians

Authors:

1. TAMAKI SATO (a)
2. YEN-NIEN CHENG (b,c)
3. XIAO-CHUN WU (d)
4. HSI-YIN SHAN (b.c)

Affiliations:

a. Tokyo Gakugei University, 4-1-1 Nukui Kita Machi, Koganei City, Tokyo 184-8501, Japan

b. National Museum of Natural Science, No.1 Kuan Chien Road, Taichung, Taiwan 40453

c. Department of Earth Sciences, National Cheng Kung University, No.1 University Road, Tainan, Taiwan 701

d. Canadian Museum of Nature, PO Box 3443 STN ‘D’, Ottawa, ON K1P 6P4, Canada

Abstract:

Diandongosaurus acutidentatus Shang, Wu & Li, 2011 is restudied on the basis of a new specimen. The new specimen provides further information on the palate of the skull, the shoulder girdle, the gastralia and hind limbs, and permits revision of the diagnosis. Newly added or modified diagnostic characters include the presence of a few small vomerine teeth, the presence of an ectopterygoid, lateral elements of gastralia distally swollen and curving dorsally, boomerang-shaped interclavicle and clavicle with a distinct anterolateral process. Slight variations in the vertebral counts, girdle morphology, and phalangeal formulae are attributed to the intraspecific variations. A revised phylogenetic analysis demonstrates that Diandongosaurus is closely related to the Nothosauroidea and that certain Chinese taxa (e.g. Keichousaurus) previously affiliated with the Pachypleurosauridae are more closely related to the Nothosauroidea. The effect of inclusion or exclusion of fragmentary taxa in the phylogenetic analysis is observed in the branching pattern of the cladogram, but it has little effect on the morphological characterization of the major clades.

China's J-20 Stealth Fighter at Dusk

Kasei Valles: One of the Great Floods of Mars

Dramatic flood events carved this impressive channel system on Mars covering 1.55 million square kilometres, shown here in a stunning new mosaic from ESA’s Mars Express.

The mosaic, which features the spectacular Kasei Valles, comprises 67 images taken with the spacecraft’s high-resolution stereo camera and is released during the week of the 10th anniversary of the spacecraft’s launch to the Red Planet.

Kasei Valles is one of the largest outflow channel systems on Mars – from source to sink, it extends some 3000 km and descends by 3 km in altitude. The scene covered in the mosaic spans 987 km north–south (19–36°N) and 1550 km east–west (280–310°E).

The channel originates beyond the southern edge of this image near Valles Marineris, and empties into the vast plains of Chryse Planitia to the east.

Kasei Valles splits into two main branches that hug a broad island of fractured terrain – Sacra Mensa – rising 2 km above the channels that swerve around it. While weaker materials succumbed to the erosive power of the fast-flowing water, this hardier outcrop has stood the test of time.

Slightly further downstream, the flood waters did their best to erase the 100 km-wide Sharonov crater, crumpling its southern rim. Around Sharonov, many small streamlined islands form teardrop shapes rising from the riverbed, carved as water swept around these natural obstacles.

The region between Sacra Mensa and Sharonov is seen in close-up detail in the perspective view below, looking downstream from the northern flank of Kasai Valles.

A Hint of Things to Come

Plankton Fossils from 3.4 Billion Years Ago Archean

Spindle-shaped inclusions in 3 billion-year-old rocks are microfossils of plankton that probably inhabited the oceans around the globe during that time, according to an international team of researchers.

"It is surprising to have large, potentially complex fossils that far back," said Christopher H. House, professor of geosciences, Penn State, and lead author.

However, the researchers not only showed that these inclusions in the rocks were biological in origin, but also that they were likely planktonic autotrophs -- free-floating, tiny ocean organisms that produce energy from their environment.

The researchers looked at marine sediment rocks from the Farrel Quartzite in Western Australia. Isotopic analysis using secondary ion mass spectrometry was carried out at UCLA. "Ken (Kenichiro Sugitani, professor, Graduate School of Environmental Studies, Nagoya University, Japan, and a co-author) discovered these unusually shaped microfossils embedded in really old rock," said House.

To determine if these inclusions were actually biological in origin, the researchers looked at 15 different samples of Farrel Quartzite and determined their stable carbon isotope ratios. The percentage of carbon 13 in the microfossils was indicative of material produced by biological processes. They found that the carbon 13 percentage in the background organic matter in the surrounding rock was different from that of the microstructures.

"When considered along with published morphological and chemical studies, these results indicate that the Farrel Quartzite microstructures are bona fide microfossils, and support the interpretation that the spindles were planktonic," the researchers report in the current issue of Geology. The morphological and chemical studies were done by Sugitani and Dorothy Oehler, who is also a co-author and research scientist, Astromaterials Research and Exploration Science Directorate, NASA -- Johnson Space Center.

The spindle-shaped microfossils are from 20 to 60 microns in length, about the size of fine sand and within the size range of today's microplankton.

Stable carbon isotope analysis can determine the biological origin of these microfossils because they used carbon dioxide to create energy and incorporated the carbon into themselves. During this process, the organisms selectively incorporate more carbon 12 than carbon 13 from the available carbon, producing a signature of biological origin.

Oehler notes that the spindles appear to be the same as those found in rocks from the Strelly Pool Formation in Western Australia and the Onverwacht Group in South Africa and Swaziland that are both 3.4 billion years old.

"The existence of these microfossils in diverse locations as far back as 3.4 billion years ago suggests that the oceans probably had life in them for a very extended period of time," said Oehler. "Moreover, this has implications beyond what we have done here, suggesting the evolution of diverse life proceeded quickly."

Sturgeons Are Far From Living Fossils

Efforts to restore sturgeon in the Great Lakes region have received a lot of attention in recent years, and many of the news stories note that the prehistoric-looking fish are "living fossils" virtually unchanged for millions of years.

But a new study by University of Michigan researchers and their colleagues reveals that in at least one measure of evolutionary change—changes in body size over time—sturgeon have been one of the fastest-evolving fish on the planet.

"Sturgeon are thought of as a living fossil group that has undergone relatively slow rates of anatomical change over time. But that's simply not true," said Daniel Rabosky, assistant professor in the U-M Department of Ecology and Evolutionary Biology and a curator of herpetology at the Museum of Zoology.

"Our study shows that sturgeon are evolving very quickly in some ways. They have evolved a huge range of body sizes. There are dwarf sturgeon the size of a bass and several other species that are nearly as big as a Volkswagen."

The sturgeon finding is just one result in a wide-ranging study of the rates of species formation and anatomical change in fish. The work involved assembling one of the largest evolutionary trees ever created for any group of animals. The evolutionary relationships between nearly 8,000 species of fish are delineated in the branches of the tree, allowing the researchers to make inferences about all 30,000 or so species of ray-finned fish.

The study's findings are scheduled for online publication in Nature Communications on June 6. Rabosky and Michael Alfaro of the University of California, Los Angeles, are the lead authors. U-M computational evolutionary biologist Stephen Smith is a co-author.

The main goal of the project was to test a longstanding idea in evolutionary biology that has anecdotal support but which had never been rigorously evaluated, Rabosky said. It was Charles Darwin who coined the term "living fossil" to describe extant creatures, such as the gar (another Great Lakes resident) and the lungfish, which have been present for many millions of years in the fossil record yet appear to have undergone very little anatomical change.

Paleontologists have long suspected that these observations reflect a fundamental coupling between the rates of species formation and anatomical change: groups of organisms that contain lots of species also seem to have greater amounts of anatomical variation, while groups with only a few species, such as the gar, lack much morphological variety.

Rabosky and his colleagues assembled a time-calibrated evolutionary tree for 7,864 living fish species using DNA sequence data and body-size information from publicly available databases. Their data set was so large that they had to develop new computer programs from scratch to analyze it.

The new computer models and the vast amount of data enabled the team to study the correlation between how quickly new species form and how rapidly they evolve new body sizes on a scale that had not previously been possible.

They found a strong correlation between the rates of species diversification and body size evolution across the more than 30,000 living species of ray-finned fish, which comprise the majority of vertebrate biological diversity.

"We're basically validating a lot of ideas that have been out there since Darwin, but which had never been tested at this scale due to lack of data and the limits of existing technologies," Rabosky said.

Most of the fish groups fall into one of two categories. Fish like the gar form species very slowly and show little range in body size. Others, like the salmon family—which includes salmon, trout, whitefish and char—do both: they form species quickly and have a wide range of body sizes.

Sturgeon have been around more than 100 million years and today consist of 29 species worldwide, including the lake sturgeon found in the Great Lakes. They don't fit the general pattern found by Rabosky's team; there are few sturgeon species but a great variety in body size.

A Simple Method for Reconciling Molecular and Fossil Divergence Dates

A Simple Method for Estimating Informative Node Age Priors for the Fossil Calibration of Molecular Divergence Time Analyses

Authors:

1. Michael D. Nowak (a)
2. Andrew B. Smith (b)
3. Carl Simpson (c)
4. Derrick J. Zwickl

Affiliations:

a. Institute of Systematic Botany, University of Zürich, Zürich, Switzerland

b. Department of Palaeontology, The Natural History Museum, London, United Kingdom

c. Museum für Naturkunde der Humboldt-Universität zu Berlin, Berlin, Germany

d. Department of Ecology and Evolution, University of Kansas, Lawrence, Kansas, United States of America

Abstract:

Molecular divergence time analyses often rely on the age of fossil lineages to calibrate node age estimates. Most divergence time analyses are now performed in a Bayesian framework, where fossil calibrations are incorporated as parametric prior probabilities on node ages. It is widely accepted that an ideal parameterization of such node age prior probabilities should be based on a comprehensive analysis of the fossil record of the clade of interest, but there is currently no generally applicable approach for calculating such informative priors. We provide here a simple and easily implemented method that employs fossil data to estimate the likely amount of missing history prior to the oldest fossil occurrence of a clade, which can be used to fit an informative parametric prior probability distribution on a node age. Specifically, our method uses the extant diversity and the stratigraphic distribution of fossil lineages confidently assigned to a clade to fit a branching model of lineage diversification. Conditioning this on a simple model of fossil preservation, we estimate the likely amount of missing history prior to the oldest fossil occurrence of a clade. The likelihood surface of missing history can then be translated into a parametric prior probability distribution on the age of the clade of interest. We show that the method performs well with simulated fossil distribution data, but that the likelihood surface of missing history can at times be too complex for the distribution-fitting algorithm employed by our software tool. An empirical example of the application of our method is performed to estimate echinoid node ages. A simulation-based sensitivity analysis using the echinoid data set shows that node age prior distributions estimated under poor preservation rates are significantly less informative than those estimated under high preservation rates.

Cosmography: Knowing Our Place in the Local Universe

Given a three-dimensional model of the solar system, almost everyone can zoom in from beyond the Oort cloud to the planet Earth and then even further to the street where they live. It is powerful shared knowledge.

But at greater distances, our geographical knowledge becomes a little blurred. Many people will have seen the extraordinary three-dimensional models of the filamentary structures that galaxies form on the larger scales in our universe.

And yet these structures remain strangely unfamiliar. Given an unlabelled three-dimensional model of this large-scale structure of the universe, who could point to the place we call home?

All that should begin to change in the next few years with the increasingly accurate maps that cosmologists are compiling of the three-dimensional distribution of galaxies within universe.

Today, Helene Courtois at the University of Lyon in France and a few buddies show off this newfound knowledge in a movie (and accompanying paper) that they’ve created to explore the rich structure of our galactic neighbourhood.

Cancer Found in Neandertal From Croatia

The first case of a bone tumor of the ribs in a Neanderthal specimen reveals that at least one Neanderthal suffered a cancer that is common in modern-day humans, according to research published June 5 in the open access journal PLOS ONE by David Frayer from the University of Kansas and colleagues from other institutions.

This discovery of a fibrous dysplasia predates previous evidence of this tumor by well over 100,000 years. Prior to this research, the earliest known bone cancers occurred in samples approximately 1000-4000 years old. The cancerous rib, recovered from Krapina in present-day Croatia is an incomplete specimen, and thus the researchers were unable to comment on the overall health effects the tumor may have had on this individual. Fibrous dysplasia in modern-day humans occurs more frequently than other bone tumors, but Frayer says that, "Evidence for cancer is extremely rare in the human fossil record. This case shows that Neandertals, living in an unpolluted environment, were susceptible to the same kind of cancer as living humans."

Neanderthals had average life spans that were likely to be half those of modern humans in developed countries, and were exposed to different environmental factors. The study concludes, "Given these factors, cases of neoplastic disease are rare in prehistoric human populations. Against this background, the identification of a more than 120,000-year-old Neandertal rib with a bone tumor is surprising, and provides insights into the nature and history of the association of humans to neoplastic disease."

All But Done: The Glowing Plant Project

What Is It About Space?

Small Modular Nuclear Reactors for the Clinch River, Tennessee

Near the banks of the Clinch River in eastern Tennessee, a team of engineers will begin a dig this month that they hope will lead to a new energy future.

They'll be drilling core samples, documenting geologic, hydrologic, and seismic conditions—the initial step in plans to site the world's first commercial small modular nuclear reactors (SMRs) here.

Once before, there was an effort to hatch a nuclear power breakthrough along the Clinch River, which happens to meander through the U.S. government's largest science and technology campus, Oak Ridge, on its path from the Appalachian Mountains to the Tennessee River.

In the 1970s, the U.S. government and private industry partners sought to build the nation's first commercial-scale "fast breeder" reactor here, an effort abandoned amid concerns about costs and safety. Today, nuclear energy's future still hinges on the same two issues, and advocates argue that SMRs provide the best hope of delivering new nuclear plants that are both affordable and protective of people and the environment. And even amid Washington, D.C.'s budget angst, there was bipartisan support for a new five-year $452 million U.S. government program to spur the technology.

At the Day Job: LBNL's NERSC Releases 10 Year Plan

In its recently released strategic plan, the National Energy Research Scientific Computing Center (NERSC) outlines its goals for the next 10 years. The high-end scientific production computing facility for DOE’s Office of Science, NERSC supports 4,500 users working on more than 700 research projects and contributes to an average 1,500 publications annually. Go here to download the report.

PDF here.

Archicebus achilles: Oldest Tarsier-like (tarsiiforme) Primate, Oldest with Skeleton

An international team of paleontologists that includes Northern Illinois University anthropologist Dan Gebo is announcing the discovery of a nearly complete, articulated skeleton of a new tiny, tree-dwelling primate dating back 55 million years.

The Eocene Epoch fossil was recovered from Hubei Province in central China.

"This is the oldest primate skeleton of this quality and completeness ever discovered and one of the most primitive primate fossils ever documented," Gebo said. "The origin of primates sets the first milestone for all primate lineages, including that of humanity.

"Although scientists have found primate teeth, jaws, occasionally skulls or a few limb bones from this time period, none of this evidence is as complete as this new skeleton from China," Gebo added. "With completeness comes more information and better evidence for the adaptive and evolutionary themes concerning primate evolution. It takes guessing out of the game."

The research team, led by Xijun Ni of the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) at the Chinese Academy of Sciences in Beijing, describes the fossil in the June 6 edition of the prestigious science journal, Nature.

paper link.  

The Cracking of Kryptos

Go read.

Barbaturex morrisoni: Lizard King of the Paleogene

Some 40 million years before rock and roll singer Jim Morrison's lyrics earned him the moniker "the Lizard King," an actual king lizard roamed the hot tropical forests of Southeast Asia, competing with mammals for food and other resources.

A team of U.S. paleontologists, led by Jason Head of the University of Nebraska-Lincoln, describes fossils of the giant lizard from Myanmar this week in the scientific journal Proceedings of the Royal Society B. Their analysis shows that it is one of the biggest known lizards ever to have lived on land.

Fittingly, it's been named for the aforementioned Doors singer: The creature's official name is Barbaturex morrisoni.

At almost six feet long and weighing upwards of 60 pounds, the lizard provides new and important clues on the evolution of plant-eating reptiles and their relationship to global climate and competition with mammals.

In today's world, plant-eating lizards like iguanas and agamids are much smaller than large mammal herbivores. The largest lizards, like the giant, carnivorous Komodo Dragon, are limited to islands that are light on mammal predators. It's not known, however, if lizards are limited in size by competition with mammals, or by temperatures of modern climates, Head said.

But B. morrisoni lived in an ecosystem with a diversity of both herbivorous and carnivorous mammals during a warm age in the earth's history -- 36 to 40 million years ago -- when there was no ice at the poles and atmospheric carbon dioxide levels were very high. The creature was larger than most of the mammals with which it lived, suggesting that competition or predation by mammals did not restrict its evolution into a giant.

"We think the warm climate during that period of time allowed the evolution of a large body size and the ability of plant-eating lizards to successfully compete in mammal faunas," Head said.

New Map of Antarctica's Bedrock

Robopocalypse: A Quadcopter Flown by Thought Alone

A remote controlled helicopter has been flown through a series of hoops around a college gymnasium in Minnesota.

It sounds like your everyday student project; however, there is one caveat…the helicopter was controlled using just the power of thought.

The experiments have been performed by researchers hoping to develop future robots that can help restore the autonomy of paralysed victims or those suffering from neurodegenerative disorders.

[...]

There were five subjects (three female, two male) who took part in the study and each one was able to successfully control the four-blade helicopter, also known as a quadcopter, quickly and accurately for a sustained amount of time.

Lead author of the study Professor Bin He, from the University of Minnesota College of Science and Engineering, said: "Our study shows that for the first time, humans are able to control the flight of flying robots using just their thoughts, sensed from noninvasive brain waves."

The noninvasive technique used was electroencephalography (EEG), which recorded the electrical activity of the subjects' brain through a cap fitted with 64 electrodes.

Facing away from the quadcopter, the subjects were asked to imagine using their right hand, left hand, and both hands together; this would instruct the quadcopter to turn right, left, lift, and then fall, respectively. The quadcopter was driven with a pre-set forward moving velocity and controlled through the sky with the subject's thoughts.

The subjects were positioned in front of a screen which relayed images of the quadcopter's flight through an on-board camera, allowing them to see which direction it was travelling in. Brain signals were recorded by the cap and sent to the quadcopter over WiFi.

"In previous work we showed that humans could control a virtual helicopter using just their thoughts. I initially intended to use a small helicopter for this real-life study; however, the quadcopter is more stable, smooth and has fewer safety concerns," continued Professor He.

After several different training sessions, the subjects were required to fly the quadcopter through two foam rings suspended from the gymnasium ceiling and were scored on three aspects: the number of times they sent the quadcopter through the rings; the number of times the quadcopter collided with the rings; and the number of times they went outside the experiment boundary.

South Korea's F-X Phase III Has Interesting Implications

If there is one misconception about South Korea's F-X Phase 3 fighter competition, due to be decided this month, it is that the requirement is aimed mainly at bolstering defense against North Korea. On the contrary, say senior government officials in Seoul, at least as strong a reason for buying 60 advanced fighters is South Korea's perceived strategic competition with Japan, China and Russia—probably in that order.

“Our neighbors are upgrading their fighter technology, so we must do so, too,” says one government official. A second official, with deep insight into the country's defense requirements, goes further: The 60 Boeing F-15Ks that South Korea has from the F-X Phase 1 and 2 programs last decade already offer enough aerial strike power for dealing with North Korea. While more big fighters would be useful if war on the peninsula broke out, the real point of the Phase 3 competition is that Japan is buying Lockheed Martin F-35As, China is developing the J-20, and Russia is working on the Sukhoi T-50 (PAK FA), says that official. Even in F-X Phases 1 and 2, North Korea was considered only part of the problem, he adds.

Little Telescope Finds a Hot Saturn, KELT-6B

A scientific team led by University of Louisville doctoral student Karen Collins has discovered a hot Saturn-like planet in another solar system 700 light-years away.

Collins announced the discovery of exoplanet KELT-6b Tuesday, June 4, during the American Astronomical Society's national meeting in Indianapolis.

Astronomers caught sight of the planet when it passed in front of, or "transited," its host star—and they've since discovered that the planet resembles one of the most famous and well-studied transiting planets, HD 209458b.

The discovery was made using inexpensive ground-based telescopes, including one specially designed to detect exoplanets and jointly operated by astronomers at Ohio State University and Vanderbilt University.

As seen from Earth, KELT-6b resides in the constellation Coma Berenices, near Leo, and has an orbit that transits its star every 7.8 days. That means a "year" on the planet lasts just over a week, and its trip across the face of its star, as seen from Earth, lasts only five hours.

Five hours may seem like a short time, but most planets found by ground-based telescopes have even shorter orbits. So catching a complete observation of KELT-6b took more patience and substantially more luck than usual – a total of seven hours of continuous telescope time with clear skies during darkness. Collins had clear skies on both of her only two opportunities to catch the planet earlier this year at UofL's Moore Observatory.

KELT-6b is now the longest-duration full planetary transit continuously observed from the ground, she said.

All Six Kepler-11 Worlds Are Light and Fluffy

ALL SIX PLANETS KNOWN TO ORBIT KEPLER-11 HAVE LOW DENSITIES

Authors:

1. Jack J. Lissauer (a)
2. Daniel Jontof-Hutter (a)
3. Jason F. Rowe (a,b)
4. Daniel C. Fabrycky (c)
5. Eric D. Lopez (d)
6. Eric Agol (e)
7. Geoffrey W. Marcy (f)
8. Katherine M. Deck (g)
9. Debra A. Fischer (h)
10. Jonathan J. Fortney (d)
11. Steve B. Howell (a)
12. Howard Isaacson (f)
13. Jon M. Jenkins (a,b)
14. Rea Kolbl (f)
15. Dimitar Sasselov (i)
16. Donald R. Short (j)
17. William F. Welsh (k)

Affiliations:

a. NASA Ames Research Center, Moffett Field, CA 94035, USA

b. SETI Institute/NASA Ames Research Center, Moffett Field, CA 94035, USA

c. Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637, USA

d. Department of Astronomy & Astrophysics, University of California, Santa Cruz, CA 95064, USA

e. Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195, USA

f. Astronomy Department, University of California, Berkeley, CA 94720, USA

g. Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA

h. Department of Astronomy, Yale University, New Haven, CT 06520-8101, USA

i. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA

j. Department of Mathematics, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA

k. Astronomy Department, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA

Abstract:

The Kepler-11 planetary system contains six transiting planets ranging in size from 1.8 to 4.2 times the radius of Earth. Five of these planets orbit in a tightly packed configuration with periods between 10 and 47 days. We perform a dynamical analysis of the system based upon transit timing variations observed in more than three years of Kepler photometric data. Stellar parameters are derived using a combination of spectral classification and constraints on the star's density derived from transit profiles together with planetary eccentricity vectors provided by our dynamical study. Combining masses of the planets relative to the star from our dynamical study and radii of the planets relative to the star from transit depths together with deduced stellar properties yields measurements of the radii of all six planets, masses of the five inner planets, and an upper bound to the mass of the outermost planet, whose orbital period is 118 days. We find mass-radius combinations for all six planets that imply that substantial fractions of their volumes are occupied by constituents that are less dense than rock. Moreover, we examine the stability of these envelopes against photoevaporation and find that the compositions of at least the inner two planets have likely been significantly sculpted by mass loss. The Kepler-11 system contains the lowest mass exoplanets for which both mass and radius have been measured.

Hula Painted Frog is Not Extinct...and Not Related to What We Thought

The first amphibian to have been officially declared extinct by the International Union for Conservation of Nature (IUCN) has been rediscovered in the north of Israel after some 60 years and turns out to be a unique "living fossil," without close relatives among other living frogs.

The Hula painted frog was catalogued within the Discoglossus group when it was first discovered in the Hula Valley of Israel in the early 1940s. The frog was thought to have disappeared following the drying up of the Hula Lake at the end of the 1950s, and was declared extinct by the IUCN in 1996. As a result, the opportunity to discover more about this species' history, biology and ecology was thought to have disappeared.

However, a team of Israeli, German and French researchers now report in the scientific journal Nature Communications on an in-depth scientific analysis of this enigmatic amphibian.

Based on new genetic analyses of rediscovered individuals and the morphologic analyses of extant and fossil bones, the conclusion is that the Hula frog differs strongly from its other living relatives, the painted frogs from northern and western Africa. Instead, the Hula frog is related to a genus of fossil frogs, Latonia, which were found over much of Europe dating back to prehistoric periods and has been considered extinct for about a million years,

The results imply that the Hula painted frog is not merely another rare species of frog, but is actually the sole representative of an ancient clade of frogs (a group with a single common ancestor)

Triceratops Trio (Family?) Found in Wyoming: Two Adults, One Juvenile

Paleontologists digging in northeastern Wyoming have uncovered fossilized remains of three triceratops—possibly the most complete specimens of the dinosaurs yet found.

The triceratops bones were initially discovered by a rancher who owns the land in Newcastle, Wyo., just west of Mt. Rushmore. What is grassland today would have looked more like a subtropical flatland when the dinosaurs called it home during the Cretaceous period. So far the dig has uncovered bones from three triceratops—two adults and a juvenile about half their size.

[...]

Paleontologists think the three dinosaurs may have been a family, which could offer new insights into triceratops behavior and development. But there isn’t a happy ending to their story. Some of the largest dinosaur’s bones appear to have been bitten through, and researchers from the Black Hills Institute of Geological Research are pointing fingers at Tyrannosaurus rex...

HA! Toroceratops takes a hit.

The Alternative to the Robopocalypse

Diet Changed For Hominins 3.5 Million Years Ago. Started Eating Grains and Grasses

A new look at the diets of ancient African hominids shows a "game changer" occurred about 3.5 million years ago when some members added grasses or sedges to their menus, according to a new study led by the University of Colorado Boulder.

High-tech tests on tooth enamel by researchers indicate that prior to about 4 million years ago, Africa's hominids were eating essentially chimpanzee style, likely dining on fruits and some leaves, said CU-Boulder anthropology Professor Matt Sponheimer, lead study author. Despite the fact that grasses and sedges were readily available back then, the hominids seem to have ignored them for an extended period, he said.

"We don't know exactly what happened," said Sponheimer. "But we do know that after about 3.5 million years ago, some of these hominids started to eat things that they did not eat before, and it is quite possible that these changes in diet were an important step in becoming human."

A paper on the subject was published online by the Proceedings of the National Academy of Sciences the week of June 3, along with three related papers. Prior to the new PNAS studies, researchers had analyzed teeth from 87 ancient hominid specimens. The new PNAS papers provide detailed information on the teeth of 88 additional specimens, including five previously unanalyzed hominid species, doubling the dataset, he said.

Sponheimer specializes in stable isotope analysis, comparing particular forms of the same chemical element, like carbon, that are present in hominid fossil teeth. The stable carbon isotopes obtained from ancient hominids helps researchers determine what types of plants they were eating, he said.

Carbon signals from hominid teeth are derived from two distinct plant photosynthetic pathways, said Sponheimer: The C3 signals are from plants like trees and bushes, while the C4 signals are from plants like grasses and sedges. The researchers also looked at the microscopic wear of hominid teeth, which provides scientists with more information on the foods they were eating, he said.

While the hominids from the genus Homo that evolved from australopithecines like the 3 million-year-old fossil Lucy -- considered by many the matriarch of modern humans -- were broadening their food choices, a short, upright hominid known as Paranthropus boisei that lived side by side with them in eastern Africa was diverging toward a more specific, C4 diet. Scientists initially had dubbed P. boisei "Nutcracker Man" because of its large, flat teeth and powerful jaws, but recent analyses indicate it might have instead used its back teeth to grind grasses and sedges, Sponheimer said.

"We now have the first direct evidence that as the cheek teeth on hominids got bigger, their consumption of plants like grasses and sedges increased," he said. "We also see niche differentiation between Homo and Paranthropus -- it looks probable that Paranthropus boisei had a relatively restricted diet, while members of the genus Homo were eating a wider variety of things. "The genus Paranthropus went extinct about 1 million years ago, while the genus Homo that includes us obviously did not."

There are some differences in the evolution of hominids in eastern Africa versus southern Africa that still puzzle researchers, said Sponheimer. Paranthropus robustus in southern Africa, for example, was very similar anatomically to its cousin, P. boisei in eastern Africa. But according to the new study, the two had very different carbon isotopic compositions in their teeth and, presumably, diets -- P. robustus seems to have been consuming a substantial amount of C3 vegetation to go along with the C4 grasses or sedges it was eating.

"This has probably been one of the biggest surprises to us so far," said Sponheimer. "We had generally assumed that the Paranthropus species were just variants on the same ecological theme, and that their diets would probably not differ more than those of two closely related monkeys in the same forest.

"But we found that their diets differed as much isotopically as those of forest chimpanzees and savanna baboons, which could indicate their diets were about as different as primate diets can be," he said. "Ancient fossils don't always reveal what we think they will. The upside of this disconnect is that it can teach us a great deal, including the need for caution in making pronouncements about the diets of long-dead critters."

Anthropologists are still pondering what the new data mean in terms of hominid evolution, climate change and changes in the environment, he said. Scientists are particularly interested in the landscapes back then, and whether different geography and/or ecosystems might have impeded or encouraged the dispersal of hominids.

Space Archaeology?

Fires, in New Mexico, From Space

Tres Lagnus above.

Thompson Ridge Fire too.

Supercontinent Cycle in Place at Archean/Proterozoic Boundary

Episodic crustal growth in the southern segment of the Trans-North China Orogen across the Archean-Proterozoic boundary

Authors:

1. Xiao-Long Huang (a)
2. Simon A. Wilde (b)
3. Jun-Wei Zhong (a, c)

Affiliations:

a. State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China

b. Department of Applied Geology, Curtin University, PO Box U1987, Perth, Western Australia 6845, Australia

c. Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming, 650093, China

Abstract:

The Dengfeng and Taihua complexes are well-exposed Neoarchean to Paleoproterozoic units in the southern segment of the Trans-North China Orogen (TNCO). Zircon U-Pb dating shows that the Dengfeng Complex records two episodes (2568 ± 11 Ma and 2306 ± 6 Ma) of tonalite–trondhjemite–granodiorite (TTG) magmatism. All of the TTG rocks are characterized by high SiO2 (66.7 − 75.4 wt%), Na2O (3.20 − 5.06 wt%) and relatively low MgO (0.40 − 1.78 wt%). The Late Neoarchean TTG gneisses have very low contents of HREE (YbN = 0.69 − 2.75) and Y (1.73 − 7.07 ppm), with moderate [La/Yb]N (24.1 − 53.8) and high Sr/Y (65.1 − 291.3) ratios. The Early Paleoproterozoic TTG gneisses have low contents of HREE (YbN = 2.93 − 6.37) and Y (6.7 − 11.0 ppm), with moderate [La/Yb]N (10.1 − 27.0) and Sr/Y (10.6 − 52.1) ratios. Both suites show pronounced negative Nb-Ta, P and Ti anomalies but positive Sr and Pb anomalies. The Late Neoarchean TTG gneisses all have similar bulk-rock Nd and zircon Hf model ages with mainly positive ɛNd(t), and are interpreted as resulting from the melting of dominantly juvenile thickened lower crust with residual garnet and amphibole. The early Paleoproterozoic TTG gneisses have extremely variable ɛNd(t) (-6.23 to + 4.23) and heterogeneous zircon ɛHf(t) (-3.3 to + 3.1), which are also best interpreted as resulting from the partial melting of thickened lower crust with residual amphibole and garnet. The Taihua Complex in the Xiaoqinling area records three episodes of Early Paleoproterozoic TTG magmatism (2.48 Ga at Caotan, 2.31 Ga at Houjiacun and 2.16 Ga at Bayuan), younger than the Taihua Complex in the Lushan area (2.85 − 2.72 Ga). All rocks have relatively low contents of HREE (YbN = 1.03 − 8.32) and Y (2.84 − 24 ppm), with moderate [La/Yb]N (8.7 − 88.4) and Sr/Y (19.8 − 125.8) ratios, and show negative Ta-Nb and Ti anomalies and positive Sr and Pb anomalies. The Caotan gneisses at 2.48 Ga and the Houjiacun TTG gneisses at 2.31 Ga have low Mg# (0.14 − 0.45), low Cr (< 42 ppm) and Ni contents (1 − 21 ppm), with variable but overall positive ɛNd(t) and ɛHf(t) values, and were derived from the partial melting of thickened lower crust with residual garnet and amphibole. The younger Bayuan TTG gneisses at 2.16 Ga have low SiO2 (57.11 − 64.89 wt%), high MgO (2.64 − 4.62 wt%), Cr (100 − 247 ppm) and Ni (32 − 80 ppm), with negative whole rock ɛNd(t) and zircon ɛHf(t) values, resulted from the partial melting of delaminated lower crust that interacted with peridotitic mantle. The geochronology of the Dengfeng Complex (in the Dengfeng area) and the Taihua Complex (in the Lushan, Xiong’er and Xiaoqinling areas) reveals at least four magmatic episodes in the southern segment of the TNCO from the Late Mesoarchean to Early Paleoproterozoic (2.85 − 2.72 Ga, 2.57 − 2.48 Ga, 2.34 − 2.30 Ga and 2.20 − 2.07 Ga). The rocks of the two early episodes are dominantly of juvenile compositions with mostly positive whole rock ɛNd(t) and zircon ɛHf(t) values, suggesting two episodes of crustal growth formed in a subduction tectonic setting. The magmatic rocks of the third episode consist of both the juvenile and pre-existing crustal materials with variable whole rock ɛNd(t) and zircon ɛHf(t) values, which were generated in a subduction zone during the initial assembly of the NCC within the Columbia supercontinent cycle. The final episode of magmatism lacks juvenile materials with whole rock ɛNd(t) and zircon ɛHf(t) values being consistently negative. These may have resulted from the orogenic collapse. The episodic continental growth recorded in the southern segment of the TNCO was caused by subduction and consequent orogeny, consistent with global supercontinent cycles within the Late Archaean and Early Paleoproterozoic.

NRO's Gift to NASA Proposed as WFIRST and the Capabilities Therein

Even though budgets are tight, this is an exciting time for NASA’s astrophysics division. New life has been breathed into NASA’s next flagship-class space telescope, the Wide Field Infra-Red Survey Telescope (WFIRST), thanks to the unbidden “gift” to NASA by the National Reconnaissance Office (NRO) of two Hubble-class telescope mirrors. They appeared on NASA’s doorstep in early 2011 and the agency, to its credit, has not ignored them.

This comes during a time of confusion and angst in the agency concerning plans for astronomy missions after the James Webb Space Telescope (JWST). The Astro 2010 Decadal Survey team had pointed to two top priorities after JWST, namely WFIRST and technology development for an exoplanet direct imaging mission. NASA had made halting progress in fulfilling these objectives in the two years since the Astro 2010 report was issued. NASA had developed a plan for WFIRST, but the scenario of when and how to initiate the mission was a bit murk in the aftermath of JWST’s budget woes. In addition, the exoplanet community has taken a beating in recent years, stunned by the cancellation of the Space Interferometry Mission) and the indefinite suspension of the Terrestrial Planet Finder (TPM). How to proceed was the subject of much debate.

In the year since NASA publicly revealed its NRO gifts, things have begun to fall into place. The agency appointed a Science Definition Team (SDT) to evaluate how WFIRST could utilize one of the 2.4-meter NRO mirrors. Now, the SDT has returned with encouraging news. The team’s final report proposes an amazingly capable design for WFIRST. As a bonus, this new WFIRST will be a bonanza for exoplanet studies. It would incorporate a coronagraph that will produce groundbreaking exoplanet science. In one fell swoop, the way forward for the top two priorities of the Astro 2010 team now seems clear.

The primary mission of WFIRST is the study of distant supernova and galaxies. These targets will be used to determine the effect of dark energy on the structure and fate of the Universe. Earlier WFIRST designs had envisioned 1.2-meter optics. The use of the NRO 2.4-meter mirrors means that WFIRST can produce wide-angle, high-resolution views that will be amazing. They will be comparable to HST’s “deep field” views, but cover an area of the sky 100 times greater. There are a number of other astrophysics fields that will benefit immensely from this capability.

The new WFIRST will be a powerful tool in the search for and study of exoplanets in a number of ways. The first is through microlensing, which takes advantage of the bending of space by massive objects, as first posited by Einstein. An exoplanet that passes in front of a distant background star (not its parent star) will cause the star’s light to be slightly magnified because of this space warp. This microlensing search was part of the original WFIRST mission. However, the use of WFIRST’s large 2.4-meter diameter mirror will allow the collection of three times as much light as its original design. This translates into a richer harvest of exoplanets and an increased ability to detect small terrestrial worlds. Overall, the microlensing survey should be able to detect several hundred exoplanets. Together with the results from Kepler, this information will give us a better understanding of the architecture of other solar systems.

Dicynodonts More Diverse In Norian Triassic North America

On the Validity and Phylogenetic Position of Eubrachiosaurus browni, a Kannemeyeriiform Dicynodont (Anomodontia) from Triassic North America

Authors:

1. Christian F. Kammerer (a)
2. Jörg Fröbisch (a)
3. Kenneth D. Angielczyk (b)

Affiliations:

a. Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity, Berlin, Germany

b. Department of Geology, Field Museum of Natural History, Chicago, Illinois, United States of America

Abstract:

The large dicynodont Eubrachiosaurus browni from the Upper Triassic Popo Agie Formation of Wyoming is redescribed. Eubrachiosaurus is a valid taxon that differs from Placerias hesternus, with which it was previously synonymized, by greater anteroposterior expansion of the scapula dorsally and a very large, nearly rectangular humeral ectepicondyle with a broad supinator process. Inclusion of Eubrachiosaurus in a revised phylogenetic analysis of anomodont therapsids indicates that it is a stahleckeriid closely related to the South American genera Ischigualastia and Jachaleria. The recognition of Eubrachiosaurus as a distinct lineage of North American dicynodonts, combined with other recent discoveries in the eastern USA and Europe, alters our perception of Late Triassic dicynodont diversity in the northern hemisphere. Rather than being isolated relicts in previously therapsid-dominated regions, Late Triassic stahleckeriid dicynodonts were continuing to disperse and diversify, even in areas like western North America that were otherwise uninhabited by coeval therapsids (i.e., cynodonts).

The Son on a Bike

Kids at a Birthday

The birthday boy has been a friend of Avrora's since they were in preschool together.  He is in the bottom (I'll rotate the pic later).  His mom is Peruvian and his dad is

Why We Need Explorers