Tuesday, December 31, 2013

30k year old Neandertal From italy is Really Modern Human From Medieval Era

A few fragmentary bones thought to be the remains of Neanderthals actually belonged to medieval Italians, new research finds.

The study is a reanalysis of a tooth, which was found in in a cave in northeastern Italy along with a finger bone and another tooth. Originally, researchers identified these scraps as belonging to Neanderthals, the early cousins of humans who went extinct about 30,000 years ago. Instead, the new study reveals the bones to belong to modern Homo sapiens.

There's no telling whom the original owner of the teeth and finger was, but the cave where they were discovered was both a hermitage, or dwelling place, and the site of a grisly medieval massacre.

US Military Arming More Drones

The U.S. Defense Department wants to arm more drones with lightweight, precision-guided weapons to support a larger range of combat missions.

As the war in Afghanistan ends and new threats emerge in the Asia-Pacific region, the Pentagon is considering adapting multiple weapons for drones, including the Cold War-era Hydra 70 rocket and the Laser Homing Attack or Anti-Tank Missile, or LAHAT, according to its latest report on the future of unmanned systems.

“Unmanned systems can be used in significantly different operating and threat conditions than manned platforms, come in a much wider range of classes and sizes than manned systems, can exhibit greater persistence and endurance than manned systems, and have the potential to support a large range of mission sets,” the recently released report states.

The 168-page document, “Unmanned Systems Integrated Roadmap: FY2013-2038,” outlines the department’s long-term strategy for adopting the technology and was approved by Frank Kendall, the Pentagon’s top weapons buyer, and Navy Adm. James Winnefeld, vice chairman of the Joint Chiefs of Staff.

The Pentagon plans to spend almost $24 billion on unmanned air, ground and maritime systems over the next five years through fiscal 2018, according to the document. While research and development funding for drones is expected to fall by $1.3 billion — more than a third — from fiscal 2013 to fiscal 2014, overall spending on the technology is expected to total at least $4.1 billion in the fiscal year that began Oct. 1.

As the department develops systems that can operate in contested areas such as the Asia-Pacific, it’s trying to find ways to arm its nearly 11,000 aerial drones with existing weapons.


South Koreans to Order Three More Aegis Equipped Warships

On December 10, the Joint Chiefs of Staff held a council, conducted by chairman of the Joint Chiefs of Staff Choi Yun-hee, and decided to secure three additional new Aegis destroyers by the mid-2020s.

Our Navy has strengthened its military strength with three Aegis ships – Sejongdaewang Ham in 2008, Yulgok Yi Yi Ham in 2010 and Seoae Ryu Seong Ryong Ham in 2012. If the Joint Chiefs of Staff secures the budget and uses it to strengthen military strength according to deliberation and decision on the Aegis, our navy will possess six Aegis ships in total.

“We’ll expand our ballistic missile detection and tracking, and anti-submarine capability to prepare for asymmetric threats from North Korea, such as nuclear weapons, missiles and submarines, and their local provocation. In real wartime, we will significantly improve our area anti-aircraft defense and striking power against surface ships and ground high-payoff targets. Moreover, for the potential threat around the Korean Peninsula, we will improve our reaction capability on the ocean sovereignty defense,” it was stated in a briefing on the results of the joint chiefs of staff’s council on the same day.

Compared to the existing Aegis destroyer (KDX-III), the new ones that will be additionally secured are loaded combat systems used for ballistic missile detection and tracking, and configured with the required operational capability to offer improved detection capability of submarines and submergence vehicles with the integrated sonar system.


Precessional Forcing Remarkably Recored in Lower Maastrichtian Cretaceous Section in France

Lower Maastrichtian cyclostratigraphy of the Bidart section (Basque country, SW France): A remarkable record of precessional forcing


Husson et al


Cyclostratigraphic analysis of the Maastrichtian limestone-marl alternations of Bidart (SW France) allows the hypothesis of orbital control on lithological cycles to be evaluated. Magnetic Susceptibility (MS), oxygen and carbon isotope measurements, sampled at a high resolution, are analyzed using various cyclostratigraphic tools. A statistically significant orbital signal is detected, with a remarkable record of the precession corresponding to the limestone-marl couplets. This well expressed orbital forcing allows the building of a relative cyclostratigraphic time scale for the MS and δ13C records based on the 100 kyr eccentricity cycle. The total duration of the section is estimated at 1.44 ± 0.22 Myr. Correlation based on calcareous nannofossil biostratigraphy and comparison of the scaled Bidart δ13C record to the astronomically calibrated δ13C signal of ODP hole 762C shows that the studied section extends from -71.5 to -70 Ma, covering the upper part of Chron C32n.1n and 2/3 of Chron C31r. Oxygen isotope data suggest a 2°C cooling of sea-surface temperatures during the studied interval. When placed on the long-term δ18O trend of the Bidart section, this interval is here recognized as the onset of the early Maastrichtian cooling event. With its excellent record of the precessional forcing, the Bidart section, along with other sections of the Basque country, is a useful tool for the refinement of the Maastrichtian timescale.

The Habitable Zones of F Class Stars

Habitability around F-type Stars


Sato et al


We explore the general astrobiological significance of F-type main-sequence stars with masses between 1.2 and 1.5 Msun. Special consideration is given to stellar evolutionary aspects due to nuclear main-sequence evolution. DNA is taken as a proxy for carbon-based macromolecules following the paradigm that extraterrestrial biology may be most likely based on hydrocarbons. Consequently, the DNA action spectrum is utilized to represent the impact of the stellar UV radiation. Planetary atmospheric attenuation is taken into account based on parameterized attenuation functions. We found that the damage inflicted on DNA for planets at Earth-equivalent positions is between a factor of 2.5 and 7.1 higher than for solar-like stars, and there are intricate relations for the time-dependence of damage during stellar main-sequence evolution. If attenuation is considered, smaller factors of damage are obtained in alignment to the attenuation parameters. This work is motivated by earlier studies indicating that the UV environment of solar-type stars is one of the most decisive factors in determining the suitability of exosolar planets and exomoons for biological evolution and sustainability.

Exoplanets Around NN Serpentis May be First Observations of Secondary Planetary Formation

Second generation planet formation in NN Serpentis?


Völschow et al


In this paper, we study the general impact of stellar mass-ejection events in planetary orbits in post-common envelope binaries with circumbinary planets like those around NN Serpentis. We discuss a set of simple equations that determine upper and lower limits for orbital expansion and investigate the effect of initial eccentricity. We deduce the range of possible semi-major axes and initial eccentricity values of the planets prior to the common-envelope event. In addition to spherically-symmetric mass-ejection events, we consider planetary dynamics under the influence of an expanding disk. In order to have survived, we suggest that the present planets in NN Ser must have had semi-major axes >∼10 AU and high eccentricity values which is in conflict with current observations. Consequently, we argue that these planets were not formed together with their hosting stellar system, but rather originated from the fraction of matter of the envelope that remained bound to the binary. According to the cooling age of the white dwarf primary of 106 yr, the planets around NN Ser might be the youngest known so far and open up a wide range of further study of second generation planet formation.

First Dinosaurs from Saudi Arabia Herald From Campanian-Maastrichtian Cretaceous

First Dinosaurs from Saudi Arabia


Kear et al


Dinosaur remains from the Arabian subcontinent are exceedingly rare, and those that have been documented manifest indeterminate affinities. Consequently the discovery of a small, but diagnostic, accumulation of elements from Campanian-Maastrichtian (~75 Ma) deposits in northwestern Saudi Arabia is significant because it constitutes the first taxonomically identifiable dinosaur material described from the Arabian Peninsula. The fossils include a series of possible lithostrotian titanosaur caudal vertebrae, and some isolated theropod marginal teeth that share unique character states and metric parameters (analyzed using multivariate statistical methods) with derived abelisaurids – this is the first justifiable example of a non-avian carnivorous dinosaur clade from Arabia. The recognition of titanosaurians and abelisaurids from Saudi Arabia extends the palaeogeographical range of these groups along the entire northern Gondwanan margin during the latest Cretaceous. Moreover, given the extreme paucity of coeval occurrences elsewhere, the Saudi Arabian fossils provide a tantalizing glimpse into dinosaurian assemblage diversity within the region.

Wrangellian Volcanism in the Late Ladinian Caused the Biotic Crisis in the Carnian Triassic?

Cause of Upper Triassic climate crisis revealed by Re-Os geochemistry of Boreal black shales


Xu et al


The Triassic Period is bracketed by two of the ‘big five’ Phanerozoic mass extinctions. Though long viewed as a period of climatic stability, emerging data suggest multiple climatic swings and at least one severe ecological crisis. Linking these climatic instabilities with probable causes is hampered by poor age control within the Triassic time scale. Here we present new Re-Os ages for shale sections straddling Middle-Upper Triassic stage boundaries. Nominal Re-Os isochron ages of 236.6 and 239.3 Ma for the top and base of the Ladinian (upper Middle Triassic) bring absolute time into the contentious Triassic time scale, and place the beginning of the Late Triassic about 12 m.y. earlier than previously assigned. A marked decrease in initial 187Os/188Os in Upper Ladinian shale records input from Wrangellian flood basalts – an instigator in the Carnian (Late Triassic) Pluvial Event and accompanying radiation of key fossil groups (e.g., dinosaurs and calcareous nanoplankton). An absolute time scale is proposed for the Anisian – Ladinian – Carnian boundaries based on Re-Os geochronology.

Another Model of the Archean Eon's Crust

Earth's mantle temperatures during the Archean eon, which commenced some 4 billion years ago, were significantly higher than they are today. According to recent model calculations, the Archean crust that formed under these conditions was so dense that large portions of it were recycled back into the mantle. This is the conclusion reached by Dr. Tim Johnson who is currently studying the evolution of the Earth's crust as a member of the research team led by Professor Richard White of the Institute of Geosciences at Johannes Gutenberg University Mainz (JGU). According to the calculations, this dense primary crust would have descended vertically in drip form. In contrast, the movements of today's tectonic plates involve largely lateral movements with oceanic lithosphere recycled in subduction zones. The findings add to our understanding of how cratons and plate tectonics, and thus also the Earth's current continents, came into being.

Because mantle temperatures were higher during the Archean eon, the Earth's primary crust that formed at the time must have been very thick and also very rich in magnesium. However, as Johnson and his co-authors explain in their article recently published in Nature Geoscience, very little of this original crust is preserved, indicating that most must have been recycled into the Earth's mantle. Moreover, the Archean crust that has survived in some areas such as, for example, Northwest Scotland and Greenland, is largely made of tonalite–trondhjemite–granodiorite complexes and these are likely to have originated from a hydrated, low-magnesium basalt source. The conclusion is that these pieces of crust cannot be the direct products of an originally magnesium-rich primary crust. These TTG complexes are among the oldest features of our Earth's crust. They are most commonly present in cratons, the oldest and most stable cores of the current continents.

With the help of thermodynamic calculations, Dr. Tim Johnson and his collaborators at the US-American universities of Maryland, Southern California, and Yale have established that the mineral assemblages that formed at the base of a 45-kilometer-thick magnesium-rich crust were denser than the underlying mantle layer. In order to better explore the physics of this process, Professor Boris Kaus of the Geophysics work group at Mainz University developed new computer models that simulate the conditions when the Earth was still relatively young and take into account Johnson's calculations.

These geodynamic computer models show that the base of a magmatically over-thickened and magnesium-rich crust would have been gravitationally unstable at mantle temperatures greater than 1,500 to 1,550 degrees Celsius and this would have caused it to sink in a process called 'delamination'. The dense crust would have dripped down into the mantle, triggering a return flow of mantle material from the asthenosphere that would have melted to form new primary crust. Continued melting of over-thickened and dripping magnesium-rich crust, combined with fractionation of primary magmas, may have produced the hydrated magnesium-poor basalts necessary to provide a source of the tonalite–trondhjemite–granodiorite complexes. The dense residues of these processes, which would have a high content of mafic minerals, must now reside in the mantle.


CEBR Projections: China's Ascent to Largest Economy Postponed Until 2028 at Least

America's economy will stay atop the world for at least another 14 years.

A new study says China won't eclipse the U.S. economy until 2028, much later than some analysts have suggested.

According to the London-based economic consultancy, the Centre for Economics and Business Research, China's rise to the world's number one economy will be much slower than previously thought, due to both strength in the U.S. economy and the relative slowdown in China's domestic economy.

"China's spectacular economic development has continued and although the increasing maturity of its economy and relatively unfavorable demographics mean that growth will inevitably slow, we still expect China to overtake the U.S. to become the world's largest economy in 2028 for the first time since 1890...This is later than some analysts have suggested," the CEBR analysts added.

According to CEBR, China's gross domestic product will grow to $33,513 billion in 2028, up from $8,939 billion in 2013.

India, meanwhile, is set to become the world's number three economy by 2028, overtaking Japan much sooner than the CEBR had previously expected.

CEBR said Japan's position in the league table had been affected by its weakening currency, which has declined roughly 20 percent against the dollar this year, and is likely to bring Japan's position down in gross domestic product terms value.

"In addition [to the weak yen] Japan's demographics are uniquely unfavorable and the combination leads to Japan losing its position as the world's third largest economy to India in 2028," added the CEBR analysts.

China's Agriculture Department Declares Over 8 Million Acres of Farm Land too Polluted for Crops, Probably Higher

More than 8 million acres of China's farmland is too polluted with heavy metals and other chemicals to use for growing food, a Cabinet official said Monday, highlighting a problem that is causing growing public concern.

The threat from pollution to China's food supply has been overshadowed by public alarm at smog and water contamination but is gaining attention following scandals over tainted rice and other crops. The government triggered complaints in February when it refused to release results of a nationwide survey of soil pollution, declaring them a state secret.

The figure given at a news conference by Wang Shiyuan, a deputy minister of the Ministry of Land and Resources, would be about 2 percent of China's 337 million acres of arable land.

Some scientists have given higher estimates of as much as 60 million acres, or one-fifth of the total, though it is unclear how much of that would be too badly contaminated for farming.

The issue poses a dilemma for communist leaders who want to maximize food production but face public pressure to ensure safety after an avalanche of scandals over shoddy infant formula and other goods.

The explosive growth of Chinese industry, overuse of farm chemicals and lax environmental enforcement have left swathes of the countryside tainted by lead, cadmium, pesticides and other toxins.

Investigations by the Ministry of Environmental Protection have found "moderate to severe pollution" on 3.3 million hectares (8.3 million acres), Wang said at a news conference.

"These areas cannot continue farming," Wang said. He did not say whether the information came from the national pollution survey.

Farmers already are prohibited from raising crops for human consumption in areas across China that are deemed too badly polluted. But tainted rice and other crops have made their way into the food supply.

Euromaidan has Pittered out

Tacitly acknowledging that street protests would not topple Ukrainian President Viktor Yanukovich, one of his leading rivals told demonstrators on Sunday that the opposition would steer the country back towards Europe after winning the next election in 2015.

Tens of thousands of people gathered on Kiev's Independence Square for what has become a weekly event since late November, when Yanukovich's government refused to sign an association agreement with the European Union and turned instead to Russia for an economic rescue package.

The turnout was visibly lower than last week, when it was estimated at about 100,000, as many Ukrainians were busy preparing for the New Year holidays and the Ukrainian Orthdox Christmas, which is celebrated on January 7.

The falling numbers have eased the pressure on the government, which is pressing ahead with forging closer ties with Russia, having secured a $15 billion bailout package from Moscow and a discount on vital Russian gas supplies.

The opposition wants the country of 46 million people to move closer to Europe and escape the grip of Russia, its former imperial master.

"We are preparing to win the presidential elections," said Arseny Yatsenyuk, the leader of the opposition Batkivshchyna (Fatherland) party. "We are building a team... that will be able to turn Ukraine into a European country."

Monday, December 30, 2013

A Botcoin Back and Forth

If I had a Bitcoin for every time a journalist has called in the last couple of months wanting to ask me about Bitcoin, I’d be very rich today and rich with variance tomorrow. The reason they come a-calling is because of this paper I wrote with Hanna Halaburda that discusses digital currencies while avoiding all meaningful discussion of Bitcoin. Anyhow, as I continue to see much that is written that is actually incorrect, I thought I’d wade in here with some thoughts.

And Krugman on bitcoin:

This is a tale of three money pits. It’s also a tale of monetary regress — of the strange determination of many people to turn the clock back on centuries of progress.

Ford to Attempt to Sell All Aluminum F Series Pickup, Shave 750 lbs off Vehicle

There are beer cans, and then there are Humvees. Ford Motor Co. will take pains to show its new, aluminum F-150 pickup has more in common with combat vehicles.

Ford will introduce an aluminum F series -- its anticipated and high-stakes redesign of the top-selling pickup in history -- at next month's Detroit auto show, according to people familiar with Ford's plans.

The automaker has asked Alcoa Inc., which makes aluminum blast shields for battlefield-bound vehicles, to lend some of its military-grade metal for the automaker's display, said one of those people, who asked not to be identified because the plans are secret.

Ford's sales job will be considerable: The company is eager to demonstrate the toughness of aluminum, which is lighter than steel, to pickup buyers who've made F-150 the bedrock of its business.

Any snafus would weigh on earnings that Ford already is projecting will decline next year and add to the challenges facing Mark Fields, likely the company's next chief executive officer.

At last year's Detroit show, he pledged that Ford would take as much as 750 pounds (340 kilograms) out of its next- generation trucks to meet tightening fuel-economy regulations.

"This is already the most significant debut at the auto show," said Joe Langley, a production analyst for researcher IHS Automotive. "Everybody's going to be dissecting that thing for a long time, especially since Ford will be taking such a big gamble."


Opinion: US Navy Torn Over Stealth Requirements for UCLASS

Life within the Naval Air Systems Command these days resembles one of TV's overheated Washington soap operas, awash with secrets, feuds and factions. The plot has had some suitably mysterious turns, like a “clerical error” that led to publication of a $20 billion solicitation for more F/A-18s in October, which was denounced so emphatically that there was obviously something to it.

But no drama is complete without a covert subplot wrapped in another secret, which is the writing of the requirement for the Unmanned Carrier Launched Airborne Surveillance and Strike (Uclass) system. There are at least two groups in the Pentagon with fundamentally different visions of what Uclass should look like, and there is not much time before a clear decision must be made.

Stealth is critical to any unmanned air system, as I pointed out nine months ago (AW&ST March 18, p. 14), because an unmanned aerial system (UAS) can't shoot back, or even evade threats very well. The Uclass debate is not about whether to have stealth, but how much of it the Navy wants to pay for.

The subject of degrees of stealth is not much discussed, because of secrecy, and because companies with big financial stakes prefer that people continue to assume that all stealth is created equal.

It's not. There have been multiple levels of stealth since Northrop's Tacit Blue demonstrated all-aspect radar cross-section (RCS) reduction and the Advanced Technology Bomber requirement that led to the B-2 and called for ultra-low RCS extending into the VHF band.

There are more levels today: The Advanced Super Hornet falls between most in-service fighters and the F-35, which in turn is not quite as good in RCS as the F-22, while the F-22—and anything else that has body parts in the same size range as VHF wavelengths—isn't the same as blended-wing-body designs, from Neuron to the RQ-180 and B-2. Russia's determined effort to field mobile, powerful VHF radars makes those distinctions more important than ever.

But the Navy wants Uclass quickly and (in Pentagon terms) cheaply. Some UAS supporters believe speed and low cost are essential to overcome opposition and inertia from a pilot-dominated community. Others don't want to see a penetrating, offensive Uclass landing on a carrier, competing too obviously with the F-35C, which looks very expensive compared to a Super Hornet and has yet to land on a carrier. Nobody forgets that the seminal studies of a carrier-based armed UAS depicted it as the air wing's key long-range strike weapon.

Tiger Team for the F-35 Software Problems

The U.S. Defense Department’s top weapons buyer is assembling a team of independent experts to study the F-35 fighter jet’s software development delays.

Frank Kendall, the Pentagon’s undersecretary of defense for acquisition, technology and logistics, was ordered to put together a group to study the issue and submit a report to Congress by March 3 as part of 2014 National Defense Authorization Act, which sets policy goals and spending targets for the fiscal year that began Oct. 1.

President Barack Obama signed the legislation into law today while vacationing with his family in Hawaii.

Air Force Lt. Gen. Christopher Bogdan, who oversees the F-35 Joint Strike Fighter, the Pentagon’s most expensive weapons acquisition program, and auditors from the Government Accountability Office, the investigative arm of Congress, have identified the aircraft’s software development “as an area of risk because of its complexity,” according to an earlier version of a report accompanying the legislation.

The Record of Forest Change in Humaitá-Western Amazonia During the Late Pleistocene

Late Pleistocene Glacial Forest of Humaitá-Western Amazonia


Cohen et al


Glacial-aged vegetation dynamics of the Humaitá-Western Brazilian Amazonia were studied by pollen, sedimentary facies, 14C dating, δ13Corg and C/Nmolar. Two sediment cores were taken to a depth of 10 and 8 m from areas covered by grassland and dense/open forest, respectively. The deposits represent a succession of sediment accumulation in active channel (greater than 42,600 cal yr B.P.), abandoned channel/floodplain (greater than 42,600 to ~ 39,000 cal yr B.P.), and oxbow lake sedimentary environments (~ 39,000 cal yr B.P. to modern). The predominance of mud sediments, depletion of δ13Corg and decrease in C/Nmolar values identify the lake establishment. In these settings, low energy subaqueous conditions were developed, locally favoring preservation of a pollen assemblage representing herbaceous vegetation, some modern taxa from Amazonia and cold-adapted plants from the Andes represented by Alnus (2 − 11%), Hedyosmum (2 − 17%), Weinmannia (0 − 18%), Podocarpus (0 − 4%), Ilex (0 − 4%) and Drymis (0 − 1%), at least between less than 42,600 and greater than 5,200 cal yr B.P. The herbs and modern taxa from Amazonia persisted through the Holocene, whilst the cold pollen assemblage became absent. The co-occurrence of Alnus with other cold adapted plants from the Andes during the late Pleistocene indicates that Alnus probably penetrated the Western Amazonia lowland or was growing closer to the study site due to cooler temperatures during glacial times. The present study presents the first report of a glacial age forest containing Alnus in areas of the Brazilian Amazonian lowlands. In addition to its palaeogeographical importance, this work demonstrates the effectiveness of using a combination of proxies for reconstructing sedimentary environments associated with vegetation.

How to Look for Lightning on Brown Dwarfs and Exoplanets

Ionisation in atmospheres of brown dwarfs and extrasolar planets VI: Properties of large-scale discharge events


Bailey et al


Mineral clouds in substellar atmospheres play a special role as a catalyst for a variety of charge processes. If clouds are charged, the surrounding environment becomes electrically activated, and ensembles of charged grains are electrically discharging (e.g. by lightning), which significantly infuences the local chemistry creating conditions similar to those thought responsible for life in early planetary atmospheres. We note that such lightning discharges contribute also to the ionisation state of the atmosphere. We apply scaling laws for electrical discharge processes from laboratory measurements and numerical experiments to Drift-Phoenix model atmosphere results to model the discharge's propagation downwards (as lightning) and upwards (as sprites) through the atmospheric clouds. We evaluate the spatial extent and energetics of lightning discharges. The atmospheric volume affected (e.g. by increase of temperature or electron number) is larger in a brown dwarf atmosphere (108− 1010m3) than in a giant gas planet's (104− 106m3). Our results suggest that the total dissipated energy in one event is greater than 1012 J for all models of initial solar metallicity. First attempts to show the infuence of lightning on the local gas phase indicate an increase of small carbohydrate molecules like CH and CH2 at the expense of CO and CH4. Dust forming molecules are destroyed and the cloud particle properties are frozen-in unless enough time is available for complete evaporation. We summarise instruments potentially suitable to observe lightning on extrasolar objects.

Luhman Using WISE Kills Nemesis and Periodicity (by proxy)



K. L. Luhman


I have used multi-epoch astrometry from the Wide-field Infrared Survey Explorer to perform a search for a distant companion to the Sun via its parallactic motion. I have not found an object of this kind down to W2 = 14.5. This limit corresponds to analogs of Saturn and Jupiter at 28,000 and 82,000 AU, respectively, according to models of the Jovian planets by Fortney and coworkers. Models of brown dwarfs by Burrows and coworkers predict fainter fluxes at a given mass for the age of the solar system, producing a closer distance limit of 26,000 AU for a Jupiter-mass brown dwarf. These constraints exclude most combinations of mass and separation at which a solar companion has been suggested to exist by various studies over the years.

Embryonic Enantiornithine Bird Fossils From Campanian Cretaceous Mongolia

An embryonic enantiornithine bird and associated eggs from the cretaceous of Mongolia


E. N. Kurochkin, S. Chatterjee and K. E. Mikhailov


Enantiornithes is the most speciose clade of Cretaceous birds, but many taxa are known from isolated postcranial skeletons. Two embryonic enantiornithine bird skeletons of Gobipipus reshetovi gen. et sp. nov. from the Upper Cretaceous (Campanian) Barun Goyot Formation of the Gobi Desert in Mongolia provide new insights into the anatomy, radiation, and mode of development of early avialans. In recent times, both enantiornithine and ornithuromorph birds are known from the Barun Goyot Formation as well as from the Djadokhta and Nemegt Formations. The 80-million-year-old Gobipipus skeletons encased within eggshells shows several features characteristic of enantiornithine birds. The wing skeleton and shoulder girdle show morphological features indicating that Gobipipus achieved sophisticated powered flight. Gobipipus reshetovi gen. et sp. nov. is quite distinct from the sympatric enantiornithine species Gobipteryx minuta from the same strata in many anatomical features. Phylogenetic analysis of 26 avialan ingroup taxa based on distribution of 202 characters indicate that Gobipipus is a basal member of enantiornithine birds along with Confuciusornis and shares more characters with ornithuromorphs than previously recognized. The embryonic nature of Gobipipus specimens sheds new light on the developmental history of enantiornithine birds. The well-ossified bones of the fore- and hind limbs, and fusion of many skeletal elements indicate a precocial mode of development in Gobipipus. Apparently Gobipipus hatchlings could walk away from the ground nests as soon as they emerged from their eggs. The asymmetry of egg poles are unique features of Gobipipus eggs (oogenus Gobioolithus) among Cretaceous avialans. The microstructure of the shell in Gobioolithus eggs with the embryos of Gobipipus is typical avian (of ornithoid basic type) and less ratite-like in morphology of the spongy layer than is that in the other possible egg-remains of enantiornitine birds (oofamily Laevisoolithidae).

Stem Therian Amphibetulimus From Bathonian Jurassic Siberia

Stem therian mammal Amphibetulimus from the Middle Jurassic of Siberia


Alexander Averianov, Thomas Martin, Alexey Lopatin and Sergei Krasnolutskii


Amphibetulimus krasnolutskii is known from the Middle Jurassic (Bathonian) Itat Formation of Krasnoyarsk Territory, West Siberia, Russia, by several edentulous and three dentigerous dental fragments, preserving p1, antepenultimate, and ultimate lower molars, and by an upper molar. It is unique among stem therians by widely open trigonids on the posterior lower molars, paraconids that are higher than the metaconids and have keeled mesiolingual vertical crests, pronounced unilateral hypsodonty of the lower molars and correlated unequal alveolar borders of the dentary ramus, and a linear Meckelian groove that is not connected to the mandibular foramen and extends along the pterygoid ridge. Amphibetulimus differs from more derived stem therians by a simple unicuspid talonid without an incipient talonid basin and a distinct labial cingulum on the upper molars. The lack of an ectotympanic facet and the long linear Meckelian groove extending onto the pterygoid ridge suggest that Amphibetulimus had a derived state of the transitional mammalian middle ear, where the ear ossicles were connected to the dentary not by a thick “ossified” Meckelian cartilage, but by a thin Meckelian cartilage, as in prenatal and early postnatal stages of some modern therians.

Russia-Belarus-Kazahkstan Customs Union Ready for 2015 Launch

Russian President Vladimir Putin said on [Christmas Eve] the final pieces were in place for the 2015 launch of an economic union with Belarus and Kazakhstan that Moscow hopes can also be joined by Ukraine.

Putin promised following talks with Kazakh President Nursultan Nazarbayev and Belarussian leader Alexander Lukashenko that the so-called Eurasian Economic Union would turn into a new source of growth for all involved.

The alliance would replace a much looser Eurasian Customs Union that Russia formed with the two ex-Soviet nations in an effort to build up a free trade rival to the 28-nation EU bloc.

"Government representatives of the troika (Russia, Kazakhstan and Belarus) ... have developed the draft of the institutional part of the Eurasian Economic Union agreement," Putin said in televised remarks.

"This document determines the international legal status, organisational frameworks, the objectives and mechanisms of how the union will operate starting on January 1, 2015," Putin said.

Putin has made the creation of a post-Soviet economic union that could one day even be joined by nations such as Turkey and India the keystone project of his third Kremlin term.

Sunday, December 29, 2013

Mapping the Plant Adaptations to Cold

A team of researchers studying plants has assembled the largest dated evolutionary tree, using it to show the order in which flowering plants evolved specific strategies, such as the seasonal shedding of leaves, to move into areas with cold winters. The researchers, including University of Minnesota professor Peter Reich, will publish their findings Sunday, Dec. 22 in the journal Nature.

Early flowering plants are thought to have been woody— maintaining a prominent stem above ground across years and changing weather conditions, such as maple trees—and restricted to warm, wet tropical environments. But they have since put down roots in chillier climates, dominating large swaths of the globe where freezing occurs. How they managed this expansion has long vexed researchers searching for plants' equivalent to the winter parka.

"Freezing is a challenge for plants. Their living tissues can be damaged. It's like a plant's equivalent to frostbite. Their water-conducting pipes can also be blocked by air bubbles as water freezes and thaws," said Amy Zanne, the study's lead author and an assistant professor of biology in the George Washington University's Columbian College of Arts and Sciences.

More than 25 scientists with a wide variety of expertise worked together on this study.

"We wanted to understand more about how plants came to have evolved the traits that allow them to withstand cold," Reich said.


Is 70 Virginis 59 light years away or almost 72 light years?

I find lots of hits on the latter, but the last source is pretty...uh...accurate.

Saturday, December 28, 2013

A Marine Refuge During the Serpukhovian Carboniferous Mass Extinction?

The Tindouf Basin, a marine refuge during the Serpukhovian (Carboniferous) mass extinction in the northwestern Gondwana platform


Cózar et al


Several macrofaunas and microfossils of the Carboniferous Saharan basins have longer stratigraphic ranges than those of other basins in the western Palaeotethys realm, particularly in the Tindouf Basin (Morocco–Algeria). Foraminifers are particularly abundant and diverse in the Serpukhovian and basal Bashkirian compared to coeval basins, and some taxa have longer ranges than in the neighbouring Reggan and Béchar basins, although this effect is more marked compared to the western Palaeotethyan assemblages in Europe. Several rugose coral species are recorded from the early Bashkirian that previously were considered to have disappeared in the Serpukhovian. The Tindouf Basin, as one of the most western Saharan basins in North Africa, shows the greatest stratigraphic ranges of taxa which diminish eastwards. Evidence for a mass extinction event during the Serpukhovian in the Tindouf Basin has not been clearly recognized, although a possible influence of glaciation is observed in the faunal diversity. Eustatic sea-level changes were experienced in Tindouf with the cyclic pattern of sedimentation, but warm water ocean currents from the palaeoequator were able to maintain tropical conditions on the platform. Tectonics in the area, led to emerging land masses and barriers, and created a partly isolated basin in this sector of the western part of the Sahara Platform in northern Gondwana. The combination of those factors controlled the environmental conditions in the area, allowing the persistence of the fauna for longer stratigraphic ranges than its equivalent counterparts in the western Palaeotethys.

Coprolite Evidence of Predation From Famennian Devonian Poland

Coprolite evidence for carnivorous predation in a Late Devonian pelagic environment of southern Laurussia


Michał ZatońCorresponding and Michał Rakociński


Small, light-brown and beige cylindrical structures found in the lower Famennian (Upper Devonian) shales and marls of the Holy Cross Mountains area, central Poland, have been investigated for the first time. Their compact, pellet-shaped morphology and the presence of various fossil fragments scattered within the phosphatic groundmass clearly indicate that they are coprolites. The coprolite inclusions are dominated by arthropod cuticle fragments followed by fish remains, one conodont, and one scolecodont. The arthropod cuticle fragments are represented by the crustacean-like thylacocephalan Concavicaris and three other different types of arthropods of uncertain affinity. The presence of some conical fragments resembling telsons from phyllocarid crustaceans suggests that some of the cuticle fragments may belong to that group of arthropods. The fish remains mainly consist of actinopterygian paleoniscoid scales and sarcopterygian teeth. Taking both fossil and facies characteristics into account, it is clear that the coprolites originated from a carnivorous pelagic fishes that hunted other fishes and swimming arthropods. Surprisingly, similar faunal contents consisting of paleoniscoid fishes, Concavicaris arthropods, and conodonts occur in situ within the body cavities of the Famennian cladoselachian sharks in the Cleveland Shale, Ohio. Such a coincidence suggests that at least some of the Famennian coprolites from Poland may have also been produced by pelagic carnivorous sharks. The preservation of defecated remains was influenced by an interplay between an oxygen-deficient benthic environment devoid of bioturbators and scavengers and rapid, microbially-driven phosphatization.

A Cryptic Coral-crinoid "Hanging Garden" From Eifelian/Givetian Devonian Morocco

Cryptic coral-crinoid "hanging gardens" from the Middle Devonian of southern Morocco


Jakubowicz et al


An unusual and exceptionally well preserved cryptic community of cnidarians, crinoids, sponges, and microbes developed in a submarine cavity of Middle Devonian age in the Hamar Laghdad area (Morocco). The biota encrusted the cavity roof and grew predominantly in an upside-down position, forming spectacular "hanging gardens." The investigated assemblage differs strikingly from both its Paleozoic and modern analogues; it constitutes one of a very few known examples of fossil cryptic assemblages developed in relatively deep water settings, and is the first report of a cryptic paleoecosystem dominated by rugose corals. The results support the view that during the middle Paleozoic there was no distinct polarization between open-surface and cryptic faunas in deep-water environments, but keen competition for space already existed in Devonian cryptic assemblages. The regional species pool seems to have been the main determinant of the ecological succession and structure of this cryptic community.

Was There a Third Pulse to the Ordovician Extinction?

The early Rhuddanian survival interval in the Lower Silurian of the Oslo Region: A third pulse of the end-Ordovician extinction


B. Gudveig Baarli


Ordovician/Silurian boundary layers with Rhuddanian strata are exposed as a long, continuously fossiliferous sequence in the Solvik Formation in the Asker area, central Oslo Region, Norway. Brachiopods belonging to Benthic Assemblage 5 are preserved in the lower parts of the formation. This level is investigated for the presence of a survival interval after the last end-Ordovician extinction event. The criteria for a survival interval include taxa that are dwarfed, long ranging, eurytopic, often opportunistic, as well as assemblages that show low density and diversity.

Four species, Isorthis prima, Leangella scissa, Dicoelosia osloensis and Eoplectodonta duplicata, were collected and measured. The three former were dwarfed as compared to a younger Aeronian fauna belonging to the same Benthic Assemblage. Detailed investigations showed a statistically significant two-step reduction in size for all but D. osloensis. The first interval, immediately above the last end-Ordovician extinction event, display dwarfed brachiopods, but diversity is high and the number of long-ranging and eurytopic species is low due to the presence of globally and locally “relict” Ordovician species. The second interval, the upper parts of lower Rhuddanian, shows all the characteristics of a survival interval in which the sizes are statistically significantly smaller than both those in the interval below and those in the Aeronian interval above. No lithological change within lower Rhuddanian strata could be linked to the pronounced reduction in size. The second step in size reduction may be related to global occurrence of anoxia in the deep oceans with a pulse of anoxic water pushed onto the shelf at that time. It is coeval with a short negative ∂13C excursion found in some locales, signifying a brief period of global warming. The results suggest a protracted extinction event through parts of the early Rhuddanian and a third and final extinction event followed by a clear survival interval.

Nailing Down Cambrian–Ordovician Transition in Baltica Provides Headaches Globally

The Cambrian–Ordovician transition in dysoxic facies in Baltica — diverse faunas and carbon isotope anomalies


Terfelt et al


The Cambrian–Ordovician boundary interval in Scandinavia is characterized by largely endemic trilobite species and fossil-meager intervals within the Alum Shale Formation. Previous investigations of this interval in Scandinavia, based on drill cores, are rather sketchy. In order to characterize the faunal signature in a largely dysoxic setting during this time interval, as well as providing biostratigraphic and chemostratigraphic data valuable for intercontinental correlation, a small strip in the outskirts of the village Södra Sandby in Scania, southern Sweden, was excavated. Nearly 5 m of the Cambrian–Ordovician boundary strata, largely represented by alum shale, were exposed and the profile was meticulously investigated for fossil content and lithological characteristics and sampled for δ13Corg analyses. The uppermost Cambrian in Sweden has previously been described as barren of fossils; however, the present study reveals a rather diverse fauna, including lingulid brachiopods, trilobites, protoconodonts, paraconodonts and euconodonts in the uppermost 1.6 m of the Furongian. The first appearance datum of planktic graptolites is represented by a single shale surface covered by specimens of Rhabdinopora flabelliforme parabola at 1.74 m above the base of the section and roughly corresponds to the Cambrian–Ordovician boundary. The conodont fauna includes several cordylodids important for intercontinental correlation. The Södra Sandby section δ13Corg data were coupled with isotope data from two Scanian drill cores, Håslöv-1 and Tosterup-2, in order to compile a composite isotope curve spanning the uppermost Ctenopyge linnarssoni Trilobite Zone in the Furongian to the upper R. flabelliforme parabola Graptolite Zone in the Lower Ordovician (Lower Tremadocian). Two isotope shifts from baseline values, observed at the base of the Peltura paradoxa Trilobite Zone and the lower part of the Peltura transiens Trilobite Zone, respectively, can be correlated with contemporaneous shifts in other parts of the world. The former, a negative shift of approximately 0.4–0.7‰, corresponds to the widely documented Top of Cambrian carbon isotope Excursion (TOCE) and the latter, a positive shift of approximately 1‰, corresponds to an as-yet-unnamed excursion at the base of the Cordylodus proavus Conodont Zone. In terms of faunal content and isotopic signals, the present study represents the first detailed description of the Cambrian–Ordovician boundary interval in Baltica. The relatively diverse fauna recorded suggests that the dysoxic environment was not a serious inhibitor for marine life. Globally, no isotope values significantly different from background values have been reported at the Cambrian–Ordovician boundary. This is confirmed by the present study; however, as the base of the Ordovician GSSP lacks meaningful isotope data, global correlation of this important boundary is problematic.

Friday, December 27, 2013

Charlie Stross Makes me LOL: If MULTICS was Judaism, UNIX is Christianity...

Yesterday, after writing my way past the notional halfway point (both of the current novel manuscript, and of the trilogy it's the middle volume of), I went and over-indulged in food and drink with friends.

Over the beer, the conversation turned—for no sane reason—to computer operating systems. There being some non-technical folks at the table, I then had to cough up a metaphor to contextualize the relationship between Mac OS X and UNIX, thuswise:

There is one true religion in operating systems, and it is UNIX. Or maybe it's not the one true faith: there's an earlier, older, more arcane religion with far fewer followers, MULTICS, from which UNIX sprang as a stripped-down rules-deficient heresy in the early days of the epoch. Either way, if MULTICS is Judaism (and the metaphor is questionable at this point, for unlike MULTICS, Judaism is still alive), then UNIX is Christianity.

Cheirolepidiacean Foliage From Valangian-Albian Cretaceous Australia

Cheirolepidiacean foliage and pollen from Cretaceous high-latitudes of southeastern Australia


Tosolini et al


Cheirolepidiaceae leaves and pollen are recorded from Valanginian–Albian strata of southeastern Australia that were deposited at high-latitudes under cool, moist climates in contrast to the semi-arid or coastal habitats preferred by many northern Gondwanan and Laurasian representatives of this group. Leaves of this family are characterized by thick cuticles and cyclocytic stomata with randomly oriented apertures, arranged in scattered or longitudinal rows or bands. Stomata are deeply sunken and surrounded by four to six subsidiary cells that bear one or two ranks of prominent overarching papillae, which may constrict the mouth of the pit. Three new taxa (Otwayia denticulata Tosolini, Cheirolepidiaceae cuticle sp. A and sp. B) are distinguished based on cuticular features, adding to several previously documented cheirolepid conifers in the Early Cretaceous of eastern Australia. Cheirolepidiaceae foliage is preserved predominantly in fluvial floodbasin settings and is interpreted to be derived from small trees occupying disturbed or low-nutrient sites. The foliage is associated with Classopollis/Corollina pollen and roots characterized by prominent mycorrhizal nodules. A Cenomanian Classopollis type recognised from Bathurst Island, Northern Australia, is recorded for the first time from the Early Cretaceous Eumeralla Formation, Otway Basin. Classopollis locally is rare in Valanginian–Barremian strata of Boola Boola, Gippsland, but constitutes up to 14% of the palynomorph assemblage in Albian strata. This indicates that the family was locally abundant in cool southern high-latitude climates of the Mesozoic, contrary to previous reports of its rarity in this region.

Studying the Mass Loss Rate of Exoplanet HD 209458b

On the sensitivity of extrasolar mass-loss rate ranges: HD 209458b a case study


Villarreal D'Angelo et al


We present a 3D hydrodynamic study of the effects that different stellar wind conditions and planetary wind structures have on the calculated Ly-α absorptions produced during the transit of HD 209458b. Considering a range of stellar wind speeds ∼[350-800] km s−1, coronal temperature ∼[3-7] ×106 K and two values of the polytropic index Γ ∼[1.01-1.13], while keeping fixed the stellar mass loss rate, we found a that a M˙p range between ∼[3-5] ×1010g s−1 give account for the observational absorption in Ly-α measured for the planetary system. Also, several models with anisotropic evaporation profiles for the planetary escaping atmosphere were carried out, showing that both, the escape through polar regions and through the night side yields larger absorptions than an isotropic planetary wind.

Accretion of Gas Giants and the Role of Vicosity

Accretion of Jupiter-mass Planets in the Limit of Vanishing Viscosity


Szulágyi et al


In the core-accretion model the nominal runaway gas-accretion phase brings most planets to multiple Jupiter masses. However, known giant planets are predominantly Jupiter-mass. Obtaining longer timescales for gas accretion may require using realistic equations of states, or accounting for the dynamics of the circumplanetary disk (CPD) in low-viscosity regime, or both. Here we explore the second way using global, three-dimensional isothermal hydrodynamical simulations with 8 levels of nested grids around the planet. In our simulations the vertical inflow from the circumstellar disk (CSD) to the CPD determines the shape of the CPD and its accretion rate. Even without prescribed viscosity Jupiter's mass-doubling time is ∼104 years, assuming the planet at 5.2 AU and a Minimum Mass Solar Nebula. However, we show that this high accretion rate is due to resolution-dependent numerical viscosity. Furthermore, we consider the scenario of a layered CSD, viscous only in its surface layer, and an inviscid CPD. We identify two planet-accretion mechanisms that are independent of the viscosity in the CPD: (i) the polar inflow -- defined as a part of the vertical inflow with a centrifugal radius smaller than 2 Jupiter-radii and (ii) the torque exerted by the star on the CPD. In the limit of zero effective viscosity, these two mechanisms would produce an accretion rate 40 times smaller than in the simulation.

Evidence of Abrupt Faunal Change at KT/K-Pg Boundary From Brazil

Tracking paleoecological and isotopic changes through the K-Pg boundary from marine ostracodes: The Poty quarry section, northeastern Brazil


Bertoglio Rodrigues et al


Ostracode assemblages of the Poty quarry, Pernambuco-Paraíba Basin, northeastern Brazil, record an abrupt faunal change near the Cretaceous-Paleogene (K-Pg) boundary. Paleoecological and stable isotope analyses of ostracode carapaces were used to interpret the paleoenvironmental changes that took place from the Late Maastrichtian to the Early Danian. Ostracode distribution demonstrates substantial changes at and around the boundary with the last occurrences of most species and appearance of new ones. Stable isotope analyses carried out for four ostracode species distributed along the entire succession exhibit oscillations in the isotopic composition before the K-Pg boundary, thus suggesting that environmental changes may have begun slightly prior the boundary event itself. These changes may have triggered the extinctions that culminated at the K-Pg boundary, marked by positive δ18O and negative δ13C excursions. The K-Pg boundary is marked by cooling of bottom seawaters and a decrease in productivity, as well as the beginning of an extensive marine regression.

Revisiting the Estimation of Dinosaur Growth Rates

Revisiting the Estimation of Dinosaur Growth Rates


Nathan P. Myhrvold


Previous growth-rate studies covering 14 dinosaur taxa, as represented by 31 data sets, are critically examined and reanalyzed by using improved statistical techniques. The examination reveals that some previously reported results cannot be replicated by using the methods originally reported; results from new methods are in many cases different, in both the quantitative rates and the qualitative nature of the growth, from results in the prior literature. Asymptotic growth curves, which have been hypothesized to be ubiquitous, are shown to provide best fits for only four of the 14 taxa. Possible reasons for non-asymptotic growth patterns are discussed; they include systematic errors in the age-estimation process and, more likely, a bias toward younger ages among the specimens analyzed. Analysis of the data sets finds that only three taxa include specimens that could be considered skeletally mature (i.e., having attained 90% of maximum body size predicted by asymptotic curve fits), and eleven taxa are quite immature, with the largest specimen having attained less than 62% of predicted asymptotic size. The three taxa that include skeletally mature specimens are included in the four taxa that are best fit by asymptotic curves. The totality of results presented here suggests that previous estimates of both maximum dinosaur growth rates and maximum dinosaur sizes have little statistical support. Suggestions for future research are presented.

A Suture–related Accretionary Wedge Formed in the Ediacaran Neoproterozoic Brazil

A suture–related accretionary wedge formed in the Neoproterozoic Araçuaí orogen (SE Brazil) during Western Gondwanaland assembly


Peixoto et al


The Araçuaí orogen represents a branch of the Brasiliano orogenic system developed between the São Francisco and Congo cratons in Neoproterozoic time. We conducted detailed studies on a complex schist belt located to the west of the Rio Doce magmatic arc, along the assumed suture zone of the Araçuaí orogen. This 30 km–wide and 100 km–long, NS–trending belt includes pelitic schists with intercalations of quartzites, metaultramafic schists and diopsidites, intruded by collisional granites. U–Pb ages from detrital zircon grains point to distinct provenances for different portions of the schist belt. The lower succession shows an age spectra and maximum depositional age (819 Ma) similar to passive margin deposits of the precursor basin. The upper succession yielded a maximum deposition age around 600 Ma, pointing toward the Rio Doce arc as the main sediment source. Thrust to the west onto the Guanhães basement and separated on the east from the Ediacaran Rio Doce magmatic arc by reverse–dextral faults, the schist belt exhibits the architecture of an asymmetric flower structure developed in transpressional regime. The distribution of metamorphic assemblages across the schist belt characterizes a collisional, Barrovian–type metamorphic zoning, in which the sillimanite, kyanite, staurolite and garnet zones are locally duplicated by thrusts. P–T conditions range from 700 °C at 7.5 kbar, at the western base of the pile, to 550 °C at 5.5 kbar, at the eastern top of the package. Zircon U–Pb ages record metamorphic overprinting on the sheared top of the basement at 560 ± 20 Ma and crystallization of collisional granites at 544 ± 10 Ma. Our results allow us to interpret the schist belt as a suture-related accretionary wedge and suggest that basin closure during the assembly of West Gondwnaland lasted to the Ediacaran-Cambrian boundary in the Araçuaí orogen.

Thursday, December 26, 2013

Tracking the Effects of Antarctic Glaciation/Deglaciation During the Paleogene on the Southern Oceans

Middle Eocene to Late Oligocene Antarctic Glaciation/Deglaciation and Southern Ocean productivity


Villa et al


During the Eocene-Oligocene transition, Earth cooled significantly from a greenhouse to an icehouse climate. Nannofossil assemblages from Southern Ocean sites enable evaluation of paleoceanographic changes and, hence, of the oceanic response to Antarctic ice sheet evolution during the Eocene and Oligocene. A combination of environmental factors such as sea surface temperature and nutrient availability are recorded by the assemblages of calcifying organisms, and can be interpreted as responses to the following changes. A cooling trend, which started in the Middle Eocene, was interrupted by transient warming during the Middle Eocene Climatic optimum and by several short cooling episodes. The cooling episode at 39.6 Ma preceded a shift toward an interval that was dominated by oligotrophic nannofossil assemblages from ~39.1 to ~36.2 Ma. We suggest that these oligotrophic conditions were associated with increased water mass stratification, low nutrient contents, and high efficiency of the oceanic biological pump that, in turn, promoted sequestration of carbon from surface waters, which favored cooling. After 36.2 Ma, we document a large synchronous surface water productivity turnover with a dominant eutrophic nannofossil assemblage that was accompanied by a pronounced increase in magnetotactic bacterial abundance. This turnover likely reflects a response of coccolithophorids to changed nutrient inputs that was likely related to partial deglaciation of a transient Antarctic ice sheet and/or to iron delivery to the sea surface. Eutrophic conditions were maintained throughout the Oligocene, which was characterized by a nannofossil assemblage shift toward cool conditions at the Eocene–Oligocene transition. Finally, a warm nannofossil assemblage in the Late Oligocene indicates a warming phase.

Data Mining 22 Months of Kepler Data Produces 472 New Potential Exoplanet Candidates


Burke et al


We provide updates to the Kepler planet candidate sample based upon nearly two years of high-precision photometry (i.e., Q1-Q8). From an initial list of nearly 13,400 Threshold Crossing Events (TCEs), 480 new host stars are identified from their flux time series as consistent with hosting transiting planets. Potential transit signals are subjected to further analysis using the pixel-level data, which allows background eclipsing binaries to be identified through small image position shifts during transit. We also re-evaluate Kepler Objects of Interest (KOI) 1-1609, which were identified early in the mission, using substantially more data to test for background false positives and to find additional multiple systems. Combining the new and previous KOI samples, we provide updated parameters for 2,738 Kepler planet candidates distributed across 2,017 host stars. From the combined Kepler planet candidates, 472 are new from the Q1-Q8 data examined in this study. The new Kepler planet candidates represent ~40% of the sample with Rp~1 Rearth and represent ~40% of the low equilibrium temperature (Teq less than 300 K) sample. We review the known biases in the current sample of Kepler planet candidates relevant to evaluating planet population statistics with the current Kepler planet candidate sample.

Using Robotic Laser-Adaptive-Optics to Image 715 Kepler Exoplanet Candidates

Robotic Laser-Adaptive-Optics Imaging of 715 Kepler Exoplanet Candidates using Robo-AO


Law et al


The Robo-AO Kepler Planetary Candidate Survey is designed to observe every Kepler planet candidate host star with laser adaptive optics imaging to search for blended nearby stars, which may be physically associated companions and/or responsible for transit false positives. In this paper we present the results from the 2012 observing season, searching for stars close to 715 representative Kepler planet candidate hosts. We find 53 companions, 44 of which are new discoveries. We detail the Robo-AO survey data reduction methods including a method of using the large ensemble of target observations as mutual point-spread-function references, along with a new automated companion-detection algorithm designed for large adaptive optics surveys. Our survey is sensitive to objects from 0.15" to 2.5" separation, with contrast ratios up to delta-m~6. We measure an overall nearby-star-probability for Kepler planet candidates of 7.4% +/- 1.0%, and calculate the effects of each detected nearby star on the Kepler-measured planetary radius. We discuss several KOIs of particular interest, including KOI-191 and KOI-1151, which are both multi-planet systems with detected stellar companions whose unusual planetary system architecture might be best explained if they are ''coincident multiple'' systems, with several transiting planets shared between the two stars. Finally, we detect 2.6-sigma evidence for less than 15d-period giant planets being 2-3 times more likely be found in wide stellar binaries than smaller close-in planets and all sizes of further-out planets.

KOI-268 has an exoplanet in the habitable zone.

Miocene Neogene Kiwi Fossils Suggest Origins

Miocene fossils show that kiwi (Apteryx, Apterygidae) are probably not phyletic dwarves


Worthy et al


Until now, kiwi (Apteryx, Apterygidae) have had no pre-Quaternary fossil record to inform on the timing of their arrival in New Zealand or on their inter-ratite relationships. Here we describe two fossils in a new genus of apterygid from Early Miocene sediments at St Bathans, Central Otago, minimally dated to 19–16 Ma. The new fossils indicate a markedly smaller and possibly volant bird, supporting a possible overwater dispersal origin to New Zealand of kiwi independent of moa. If the common ancestor of this early Miocene apterygid species and extant kiwi was similarly small and volant, then the phyletic dwarfing hypothesis to explain relatively small body size of kiwi compared with other ratites is incorrect. Apteryx includes five extant species distributed on North, South, Stewart and the nearshore islands of New Zealand. They are nocturnal, flightless and comparatively large birds, 1–3 kg, with morphological attributes that reveal an affinity with ratites, but others, such as their long bill, that differ markedly from all extant members of that clade. Although kiwi were long considered most closely related to sympatric moa (Dinornithiformes), all recent analyses of molecular data support a closer affinity to Australian ratites (Casuariidae). Usually assumed to have a vicariant origin in New Zealand (ca 80–60 Ma), a casuariid sister group relationship for kiwi, wherein the common ancestor was volant, would more easily allow a more recent arrival via overwater dispersal.

New Zealand Holocene Quaternary Giant Moas may not Have Been Robust Birds

Giant moa bird (Dinornis robustus, literally meaning 'robust strange bird') may not have actually had robust bones, according to new research conducted by The University of Manchester. The leg bones of one of the tallest birds that ever existed were actually rather like those of its modern (but distant) relatives, such as ostrich, emu and rhea, the studypublished in PLOS One today (18 December) shows.

The study, led by biomechanics researcher Charlotte Brassey, in collaboration with palaeobiologist Professor Richard Holdaway at the University of Canterbury in New Zealand, has found that the largest of the moa species had leg bones similar to those of modern flightless birds that can run fast, whereas a much smaller species of moa – from a different family - had an extremely robust skeleton.

Ms Brassey said:"Our research suggests that this group of birds came up with several different solutions to deal with the problem of supporting the large body necessary to process a diet of coarse vegetation.

"We know that these species of moa were living together in the same locations, at the same time. So we don't think the differences we're seeing in leg robustness are adaptations to a particular habitat type.

"Instead it seems they were perhaps engaging in different behaviours, although both could deal with extremely rough terrain."

Nitrogen and Organic Carbon Analysis of the Ediacaran/Cambrian Boundary in South China

Nitrogen and organic carbon isotope stratigraphy of the Yangtze Platform during the Ediacaran-Cambrian transition in South China


Cremonese et al


N and Corg isotope results are presented from six sections along a West–east transect in the South China Basin (SCB) covering both shallow and deeper domains, in order to investigate biogeochemical cycling, stratigraphic correlation and isotope systematics over the crucial Ediacaran-Cambrian transition. δ15N bulk values range between − 3‰ and + 7‰, while δ13Corg values range between − 21‰ and − 39‰. Similar isotopic trends have been identified for both these proxies across the basin, although hiatuses, differences in depositional setting and syn-depositional bacterial fermentation may have caused some inconsistencies. A trend towards negative N isotope values can be recognized above the PC-C boundary in both shallow and deeper basin realms across the Yangtze platform. This negative δ15N excursion is probably a response to photic zone anoxia and intense nitrogen fixation/assimilation by diazotrophic cyanobacteria and Green/Purple Sulfur Bacteria (GSB and PSB). The Xiaotan section and a composite section from the Yangtze Gorges area show meaningful similarities in their nitrogen isotope trends, interpreted as chemocline fluctuations in the water column that testify to rapid mixing of water overlying the shallow platform. Using carbon isotope stratigraphy, we correlate boundary strata across the platform to test the wider significance of nitrogen isotopic variations. Increased bioturbation and food-chain complexity across the Ediacaran-Cambrian transition probably led to more frequent variations in nitrate isotope composition and related pool dimension during the early Cambrian, reflecting the beginning of a new more biologically controlled era.

China Set to Relax One-Child Policy 1Q2014, Will There be a Baby Boom?

Changes to China's strict one child policy, which will allow more parents to have a second child, will begin to roll out early next year, the country's family planning commission told official media late on Monday.

The policy change is expected to go into force in some areas of China in the first quarter of 2014, Yang Wenzhuang, a director at the National Health and Family Planning Commission told China's official Xinhua news agency.

Beijing said last month it would allow millions of families to have two children, the most radical relaxation of its strict one-child policy in close to three decades. The move is part of a plan to raise fertility rates and ease the financial burden of China's rapidly ageing population.

Wednesday, December 25, 2013

Toarcian Jurassic Oceanic Anoxic Event Evidence From Foraminifera and Ostracods Isotopic Evidence

Stable isotopes on foraminifera and ostracods for interpreting incidence of the Toarcian Oceanic Anoxic Event in Westernmost Tethys: Role of water stagnation and productivity


Matías Reolid


The analysis of δ13C and δ18O from whole rock and the shells of selected foraminifera (Lenticulina and Dentalina) and bairdioid ostracods from Lower Toarcian of the South Iberian Palaeomargin (Western Tethys) is presented with the aim of improving knowledge of the processes and the environmental effects of the Toarcian Oceanic Anoxic Event. In addition, isotopic data are compared with geochemical redox and palaeoproductivity proxies. The microhabitat affected δ13C values, δ13CLenticulina generally being lower than δ13CDentalina due to more depleted 13C values for sediment pore-water in the deep infaunal microhabitat. The lowest values of δ13C (lower part of Serpentinum Zone) happen during suboxic conditions, as indicated by redox proxies, low diversity and abundance of foraminifera and higher TOC values. The fine-grained, organic rich sediments allow for conditions favouring pore-water dissolved inorganic carbon that is depleted in 13C with respect to that of the bottom sea-water, particularly during the suboxic conditions. The δ13C of potential deep infauna (Lenticulina) reflects the oxygen restricted conditions better than shallow infauna (Dentalina) and whole sediment. Regarding δ18O, values from bulk rock present stronger fluctuations and lower values than δ18ODentalina and δ18OLenticulina. The stratigraphic differences between δ18ODentalina and δ18OLenticulina correspond to vital effects, since no important fluctuations in temperature occurred in the bottom sea-water, as deduced from the absence of peaks and stratigraphic trends in the interval studied. The δ18O values do not allow us to infer temperature changes related to the Toarcian Oceanic Anoxic Event in this part of the palaeomargin.

Exploring the Atmospheres of Hot Neptune and Gas Giant Exoplanets



Y. Miguel and L. Kaltenegger


We calculated an atmospheric grid for hot mini-Neptune and giant exoplanets that links astrophysical observable parameters—orbital distance and stellar type—with the chemical atmospheric species expected. The grid can be applied to current and future observations to characterize exoplanet atmospheres and serves as a reference to interpret atmospheric retrieval analysis results. To build the grid, we developed a one-dimensional code for calculating the atmospheric thermal structure and linked it to a photochemical model that includes disequilibrium chemistry (molecular diffusion, vertical mixing, and photochemistry). We compare the thermal profiles and atmospheric composition of planets at different semimajor axes (0.01 AU ≤ a ≤ 0.1 AU) orbiting F, G, K, and M stars. Temperature and UV flux affect chemical species in the atmosphere. We explore which effects are due to temperature and which are due to stellar characteristics, showing the species most affected in each case. CH4 and H2O are the most sensitive to UV flux, H displaces H2 as the most abundant gas in the upper atmosphere for planets receiving a high UV flux. CH4 is more abundant for cooler planets. We explore vertical mixing, to inform degeneracies on our models and in the resulting spectral observables. For lower pressures, observable species like H2O or CO2 can indicate the efficiency of vertical mixing, with larger mixing ratios for a stronger mixing. By establishing the grid, testing the sensitivity of the results, and comparing our model to published results, our paper provides a tool to estimate what observations could yield. We apply our model to WASP-12b, CoRoT-2b, XO-1b, HD189733b, and HD97658b.

Warm Neptune Exoplanet GJ 3470b's Atmosphere

The atmospheric chemistry of the warm Neptune GJ 3470b: influence of metallicity and temperature on the CH4/CO ratio


Venot et al


Current observation techniques are able to probe the atmosphere of some giant exoplanets and get some clues about their atmospheric composition. However, the chemical compositions derived from observations are not fully understood, as for instance in the case of the CH4/CO abundance ratio, which is often inferred different from what has been predicted by chemical models. Recently, the warm Neptune GJ3470b has been discovered and because of its close distance from us and high transit depth, it is a very promising candidate for follow up characterisation of its atmosphere. We study the atmospheric composition of GJ3470b in order to compare with the current observations of this planet, to prepare the future ones, but also as a typical case study to understand the chemical composition of warm (sub-)Neptunes. The metallicity of such atmospheres is totally uncertain, and vary probably to values up to 100x solar. We explore the space of unknown parameters to predict the range of possible atmospheric compositions. Within the parameter space explored we find that in most cases methane is the major carbon-bearing species. We however find that in some cases, typically for high metallicities with a sufficiently high temperature the CH4/CO abundance ratio can become lower than unity, as suggested by some multiwavelength photometric observations of other warm (sub-)Neptunes, such as GJ1214b and GJ436b. As for the emission spectrum of GJ3470b, brightness temperatures at infrared wavelengths may vary between 400 and 800K depending on the thermal profile and metallicity. Combined with a hot temperature profile, a substantial enrichment in heavy elements by a factor of 100 with respect to the solar composition can shift the carbon balance in favour of carbon monoxide at the expense of CH4. Nevertheless, current observations of this planet do not allow yet to determine which model is more accurate.

Did the Ancestor of Extant Squamates (Lizards, Snakes) Give Birth to Live Young?

The ancestor of snakes and lizards likely gave birth to live young, rather than laid eggs, and over time species have switched back and forth in their preferred reproductive mode, according to research published in print in Ecology Letters Dec. 17.

"This is a very unusual and controversial finding, and a major overturn of an accepted school of thought," said Alex Pyron, Robert F. Griggs Assistant Professor of Biology in the Columbian College of Arts and Sciences at the George Washington University. "Before, researchers long assumed that the ancestor of snakes and lizards laid eggs, and that if a species switched to live birth, it never reverted back. We found this wasn't the case."

The findings push researchers' understanding of the evolution of live birth a lot further back in time to 175 million years ago, showing that live birth has a much more ancient past as a strategy than previously believed. The findings are backed by several recent plesiosaur and mosasaur fossil discoveries and the fossil record of a few lizards from the Cretaceous Period, which had embryos in the mother and had live birth.

Dr. Pyron analyzed an evolutionary tree containing all groups of squamates—the group that comprises lizards and snakes—which he and a team of researchers published in the journal BMC Evolutionary Biology earlier this year. The tree, which uses DNA sequencing technology to group thousands of lizards and snakes, includes all families and subfamilies and most genus and species groups.

A Tooth Wear Pattern Study of the Durophagus Maastrichtian Cretaceous Mosasaur Carinodens belgicus

Dental macro- and microwear in Carinodens belgicus, a small mosasaur from the type Maastrichtian


Holwerda et al


Teeth of the small durophagous mosasaur Carinodens belgicus are known from Maastrichtian Atlantic-Tethyan deposits worldwide. The peculiar dentition of Carinodens inspired debate and speculation on its dietary niche ever since its first description. In this contribution, we describe the macro- and microwear pattern in five well-preserved isolated teeth, allowing further and independent evaluation of aspects of feeding behavior and diet. Macroscopically, wear is concentrated on the apex and mesiodistal sides. Microwear was mapped using Scanning Electron Microscopy at several magnifications and can be characterised as scratches and pits. Coarse scratches were found to be the most common and pits were found to be the least common feature. Scratch orientation is primarily along the mesiodistal plane or in the labiolingual plane with an angle of ~130°. These microwear features can be explained either by oral processing or passive abrasion by sediments or food. As scratch width only indicates the minimum width of the abrading particle, the material causing the wear here could have ranged from silica-based silts to larger abrasives. However, in this case, abrasion by sediments might not explain this wear because of the biocalcarenitic nature of the type Maastrichtian sediments; siliciclastics are virtually absent. Therefore it is more likely that hard food particles, such as benthic organisms with hard exoskeletons, caused the wear on the enamel of Carinodens, or Carinodens ventured out to more sandy areas to forage as well. The mesiodistal and labiolingual direction of the microwear scratches might suggest that Carinodens showed more complexity in the use of its teeth than simple grasping, and that a gripping and pulling motion during feeding similar to that employed by modern varanids may have been the cause.

More Trace Fossil Evidence of Animals in the Ediacaran From South China

Interactions between Ediacaran animals and microbial mats: Insights from Lamonte trevallis, a new trace fossil from the Dengying Formation of South China


Meyer et al


A new ichnogenus and ichnospecies, Lamonte trevallis, is formally described from the Shibantan Member limestone of the upper Ediacaran Dengying Formation, Yangtze Gorges area, South China. It is characterized by horizontal tunnels connected with short vertical burrows and surface trails. The horizontal burrows are elliptical or bilobed in transverse cross-section, preserved in full relief, and filled with carbonate intraclasts, micrites, as well as calcite and silica cements. They occur exclusively in silty, crinkled, and microlaminated layers that are interpreted as amalgamated cyanobacterial microbial mats; no burrows have been found in intraclastic layers adjacent to the microlaminated layers. The vertical traces are filled with the same material as the burrows, but they typically project through the crinkled microlaminae and are exposed on the bedding surface. The surface tracks are always preserved in negative epirelief or positive hyporelief and consist of two parallel series of either sharp scratch marks or small knobs. The burrow infill has δ18Ocarb and δ13Ccarb values distinct from, but intermediate between, microlaminated and intraclastic layers, consistent with petrographic observation that burrow infill consists of a mixture of early carbonate cements, intraclasts, and micrites. Bedding plane bioturbation intensity (20–40%)—measured as percentage of bedding plane area covered by L. trevallis traces—is comparable to similar measurements in pre-trilobite Cambrian carbonates. The exclusive occurrence of L. trevallis within microbial mats may have both taphonomic and ecological significance. These mats may have provided firm substrates and localized geochemical conditions that contributed to the structural integrity of the burrows, and they may have also facilitated early diagenetic cementation of burrow infill, thus facilitating burrow preservation. The close association of these burrows with microbial mats implies that the trace producers actively mined cyanobacterial mats to exploit oxygen or nutrient resources. The trace makers of L. trevallis were better able to utilize the resources around them than many other Ediacaran trace makers and provide an ichnological record of a flourishing benthic ecology in late Ediacaran oceans at the dawn of the agronomic revolution.

First Flight of China's Z-20 "Copyhawk"


2nd link.