The Dragon's Tales

Take With a Grain of Salt: North Koreans Claim Ediacaran Fossils

2009-11-24T15:25:00.000-08:00

North Korean researchers have discovered a 620,000,000-year-old fossil of a tubular animal, the first organism with skeletal structure on Earth, the state media reported today.

Researchers from the geology faculty of Kim Il Sung University excavated the fossil of the tubular animal in the Proterozoic era of North Hwanghae province, the Korean Central News Agency (KCNA) said in a report.

According to the report, the tubular animal was the first organism with skeletal structure on Earth. It was an elliptic tube-shape animal with nothing in abdomen.

The researchers said they found fossils of primitive seaweeds and primitive jellyfish belonging to the period of transition from one-cell to multi-cell in 2001.

During their recent in-depth research into the fossil, they discovered the fossil of the 5 cm-long tubular animal again on the same stratum, Xinhua news agency quoted KCNA as saying.

hmmm.

The Big Five Mass Extinctions Hit Open Water Oceans Harder

2009-11-24T12:21:00.000-08:00

For many years, paleobiological researchers interested in the history of biodiversity have focused on charting the many ups (evolutionary radiations) and downs (mass extinctions) that punctuate the history of life. Because the preserved record of marine (sea-dwelling) animals is unusually extensive in comparison, say, to that of terrestrial animals such as dinosaurs, it's been easier to accurately calibrate the diversity and extinction records of marine organisms.

“Paleontologists now recognize that there were five particularly large, worldwide mass extinction events during the history of life, known among the cognoscenti as ‘The Big Five,’” says Miller. “Much ink in research journals has been spilled over the past few decades on papers investigating the causes of these events.”

Although researchers have long understood the potential value of “dissecting” mass extinctions, to ask whether some environments and organisms were affected more dramatically than others, little attention has been paid to a major dichotomy observed among marine sedimentary rocks and fossils: the distinction between epicontinental seas, which were broad shallow seas (typically less than 100 meters in depth) that once covered large regions of present-day continents, and open-ocean-facing coastlines, such as the continental shelves that rim many continents.

Today, it is difficult to appreciate that there was a time when regions such as Cincinnati were once covered by epicontinental seas, which gradually diminished over time so that almost none are left in the present day. And yet, a large percentage of Earth’s fossil record is associated with these settings in the geological past, and there are many reasons to believe that their environmental properties were very different from open-ocean settings.

For one thing, because they were so broad and relatively flat, drops in sea level should have had more drastic effects on epicontinental seas because large regions could have been drained entirely in a short amount of time. On the other hand, the sluggish circulation associated with epicontinental seas may have inhibited the spread of the waterborne effects of such events as volcanic eruptions and asteroid impacts, which may have been more effective killing agents in open oceans.

In their research, Miller and Foote assembled data on the occurrences of marine genera from the Paleobiology Database for the Permian through Cretaceous periods, during which both major settings are well preserved in the fossil record. From that, they determined whether these occurrences were from epicontinental seas or open-ocean-facing settings, and they then compared extinction and origination rates in the two settings throughout the interval.

“This was a particularly juicy interval to work with, because it includes three of The Big Five, including the Late Permian mass extinction, the largest extinction in the history of marine animal life, and the end-Cretaceous event, which also did in the dinosaurs and has been associated previously with the impact of a big comet or asteroid,” Miller says.

Miller and Foote found that, while extinction rates in the two settings did not generally differ from one another during “background” times between mass extinctions, there was a strikingly different pattern for the mass extinctions: extinctions rates during mass extinctions were significantly higher in open-ocean-facing settings than in epicontinental seas, indicating that open-ocean settings were more susceptible to the mass-extinction-causing agents.

The only exception to Miller and Foote’s basic finding was an interval of heightened extinction in the run-up to the big event at the end of the Permian, during which the extinction rate was higher in epicontinental seas. But this interval had already been fingered by previous researchers as one in which there was a big sea-level decline, so Miller and Foote’s finding bolsters the view that a drop in sea level was uniquely important as a cause of extinction in that interval.

For their analysis, Miller and Foote looked at several hundred thousand occurrences of fossils throughout the world assembled from the Paleobiology Database and used paleogeographic maps on which they had delineated the boundaries of epicontinental seas to determine whether individual occurrences were from epicontinental seas or the open ocean. “We then determined from these occurrences whether a given genus had a statistically significant tendency to occur in one setting more often than in the other, and if so, it was classified as open-ocean ‘loving’ or epicontinental-sea ‘loving,’” Miller explains. “Our assessments of extinction and origination rates for the two settings were based on these assignments.”

[...]

“One clear outcome of our analyses is that different marine environments respond differently to agents of mass extinction,” says Miller. “Given present-day concerns that physical agents such as the accelerated pace of global warming may be inducing a ‘sixth’ extinction, we might also ask whether some present-day marine settings are likely to be more susceptible than others to the effects of extinction-causing agents.”

Interesting, but no time to comment.

Orest Sleeping

2009-11-21T15:41:00.000-08:00

I think My Canadian Readers Need To Do Some Explaining...

2009-11-20T07:28:00.000-08:00

According to a business survey done by PriceWaterhouseCoopers here are the rankings for fraud:

1. Russia.
2. South Africa
3. Kenya
4. CANADA
5. Mexico.

Hat tip to Gancho.

Care to 'splain that you not so corrupt ones? ;)

HELLADS: DARPA's Laser Weapons Takes Another Step Forward

2009-11-19T13:55:00.000-08:00

DARPA is getting ready to move to the next phase of its High Energy Liquid Laser Area Defense System (HELLADS) program to demonstrate a laser weapon system compact enough to be carried on board a tactical aircraft - say a B-1B bomber or an AC-130 gunship - without affecting their ability to perform traditional missions.

The research agency has signalled its intent to award a 24-month contract to either or both of the HELLADS developers - General Atomics and Textron Defense Systems - to build and ground-test a 150kW laser compatible with the requirement for a weapon-system weight of 750kg.

Story over at Ares. We're getting really close to a shake up. We're now talking less than a decade for lasers to become deadly weapons on the battlefield. Without the noxious chemicals.

Yet Another Hobbits Are A New Human Species Study

2009-11-19T13:51:00.000-08:00

Researchers from Stony Brook University Medical Center in New York have confirmed that Homo floresiensis is a genuine ancient human species and not a descendant of healthy humans dwarfed by disease. Using statistical analysis on skeletal remains of a well-preserved female specimen, researchers determined the "hobbit" to be a distinct species and not a genetically flawed version of modern humans. Details of the study appear in the December issue of Significance, the magazine of the Royal Statistical Society, published by Wiley-Blackwell.

In 2003 Australian and Indonesian scientists discovered small-bodied, small-brained, hominin (human-like) fossils on the remote island of Flores in the Indonesian archipelago. This discovery of a new human species called Homo floresiensis has spawned much debate with some researchers claiming that the small creatures are really modern humans whose tiny head and brain are the result of a medical condition called microcephaly.

Researchers William Jungers, Ph.D., and Karen Baab, Ph.D. studied the skeletal remains of a female (LB1), nicknamed "Little Lady of Flores" or "Flo" to confirm the evolutionary path of the hobbit species. The specimen was remarkably complete and included skull, jaw, arms, legs, hands, and feet that provided researchers with integrated information from an individual fossil.

Need! More! Fossils!

Paper here.

Ocean Carbon Uptake Topping Out

2009-11-19T13:45:00.000-08:00

The world's oceans, which normally gobble up carbon dioxide, are getting stuffed to the gills, according to the most thorough study to date of human-made carbon in the seas.

Between 2000 and 2007, as emissions of the potent greenhouse gas carbon dioxide skyrocketed, the amount of human-made carbon absorbed by the oceans fell from 27 to 24 percent.

In terms of ocean processes, "that's a pretty large drop, and the trend is pretty clear: The ocean can't keep up with [human-made carbon]," said study leader Samar Khatiwala, an oceanographer at Columbia University's Lamont-Doherty Earth Observatory.

Khatiwala is careful to point out that the total uptake of carbon is not declining—the rate is just not growing as fast as it used to.

But if the oceans continue to be overwhelmed by carbon, more of the gas will remain in the already warming atmosphere, the authors say.

"Ultimately the ocean is what's controlling what's going on here," said Chris Sabine, a supervisory oceanographer at NOAA's Pacific Marine Environmental Laboratory in Seattle, Washington, who was not involved in the research.

"It's a big deal that it's becoming less efficient in taking up CO2."

It's hitting a wall. Considering that emissions went up in that time frame - this past year up 2% despite the economic slow down and driven by China, not the US - the drop is less than they imply, but still there.

Another Step to the Robo Future

2009-11-19T13:36:00.000-08:00

On Oct. 27, 2004, a suicide bomber riding a motorcycle blew himself up alongside a U.S. Army flatbed truck in Balad, in north-central Iraq. The blast killed the truck’s driver, Staff Sgt. Jerome Lemon, from the South Carolina-based 1052nd Transportation Company.

Nearly five years later, at a sandy outdoor range at the Massachusetts Institute of Technology, an unassuming orange-and-black-painted forklift approached and lifted a pallet of mock munitions, as an audience of Army officers looked on. It might have looked like any day at any austere supply depot, but for one thing: the forklift had no driver.

While separated by years and thousands miles, there’s a direct link between Lemon’s tragic death and the robotic forklift’s quiet feat. From warehouses to highways to supply depots, the Pentagon is working hard to replace human logisticians like Lemon with machines that cannot be killed. After several years of intensive development, the first supply bots are just beginning to crawl and fly towards battlefields in Iraq and Afghanistan.

A story from War is Boring.

MUHAHAHAHAHAHA!

Robo future is getting here.

However, while I'm excited about the idea of being able to radically downsize the logistics portion of the army (less guys and gals on the tail end and more combatants), this has enormous potential for the civie sector. Just imagine what we could do at the dock yards! You could completely shift the workers away from unloading to inspecting. Even that could be automated in a way.

We need construction and produce picking bots still.

Cretaceous Gondwanan Crocodyliform Diversity

2009-11-19T13:25:00.000-08:00

A suite of five ancient crocs, including one with teeth like boar tusks and another with a snout like a duck's bill, have been discovered in the Sahara by National Geographic Explorer-in-Residence Paul Sereno. The five fossil crocs, three of them newly named species, are remains of a bizarre world of crocs that inhabited the southern land mass known as Gondwana some 100 million years ago.

Sereno, a professor at the University of Chicago, and his team unearthed the strange crocs in a series of expeditions beginning in 2000 in the Sahara. Many of the fossils were found lying on the surface of a remote, windswept stretch of rock and dunes. The crocs galloped and swam across present-day Niger and Morocco when broad rivers coursed over lush plains and dinosaurs ruled.

"These species open a window on a croc world completely foreign to what was living on northern continents," Sereno said. The five crocs, along with a closely related sixth species, will be detailed in a paper published in the journal ZooKeys and appear in the November 2009 issue of National Geographic magazine. The crocs also will star in a documentary, "When Crocs Ate Dinosaurs," to premiere at 9 p.m. ET/PT Saturday, Nov. 21, on the National Geographic Channel.

Extensively covered here, here, here, here, here, and here at least. Paper here.

Avrora and the Rocket

2009-11-19T07:10:00.001-08:00

This is from Sat when Lyuda had the baby welcoming party.

Everybody Sick

2009-11-19T07:08:00.000-08:00

Even Orest. We think its that nasty flu. We're on the mend though.

New Top 500 Supercomputers List Released

2009-11-17T08:59:00.000-08:00

From the top 25, 15 are American systems, 2 German, 2 Chinese, 1 Russian, 1 South Korean, 1 Saudi Arabian, 1 Canadian, 1 Brit, and 1 Swiss. *NO*JAPANESE*.

This used to be a tit for tat between the Americans and Japanese, but it seems the rest of the world is joining in now. A list by country for HPC assets, percent of total, is located here.

Once upon a time, this was almost an entirely American list, by the way. Now we have only 55% of it.

PS: Boo hiss! NERSC is at #15!

PPS To even get on the list, you need to have 20 teraflops sustained. That's huge. Soon we will surpass the point where the Earth Simulator doesn't belong on the list at all.

An Ectothermic Mammal Found?

2009-11-16T15:50:00.000-08:00

A prehistoric goat survived for millennia on a resource-poor island by living like a reptile—changing its growth rate and metabolism to match the available food supply, according to a new study of the animal's bones.

The discovery marks the first time scientists have seen this cold-blooded survival strategy in mammals.

[...]

Fossils of the ancient goat, called Myotragus, were first found on Majorca in the early 1900s. The bones show the species lived on the island for more than five million years.

[...]

But the new study, which looked at the bone histories of several Myotragus individuals, revealed that the goats may have fine-tuned their growth and metabolic rates both seasonally and during irregular times such as droughts—just like reptiles.

"This way, it burned only the energy that was available from the environment, slowing down the 'fire of life' in times when resources became scarce," Köhler said.

The lizard-like lifestyle, however, meant that Myotragus's newborns were extremely small—the sizes of large rats—and the young took years to reach adult size.

The goat also saved a lot of energy in its nervous system—among the body's most "costly" tissues—by sporting a brain only half the size of a similar-size hoofed mammal and eyes only a third as large.

The combined effect was that Myotragus was sluggish, with slow reaction times, the bone study suggests.

Like modern-day reptiles, the goats probably "saved as much energy as possible just lying around and basking in the sun," Köhler said.

"The postcranial skeleton indicates that this animal was not able to run, jump, or move fast around, and [would have been] easy prey."

Someone have a link to the paper? I'd like to see if this is really the case that the goat lost endothermy. It has been posited for crocs, but not many other animals.

Note the brain size decrease, folks.

Did A Giant Asteroid Stir The Oceanic Pot?

2009-11-12T10:45:00.000-08:00

The collision of a large extraterrestrial object with Earth almost 2 billion years ago may have stirred the seas worldwide and delivered a huge serving of oxygen to the deep ocean.

The Sudbury impact, named after the Canadian city located near the center of what remains of the ancient crater, happened around 1.85 billion years ago (SN: 6/15/02, p. 378). Despite erosion since then, the impact structure —at least 200 kilometers across — is recognized to be the second-largest on the face of the planet, says William Cannon, a geologist with the U.S. Geological Survey in Reston, Va., and coauthor on a paper in the November Geology. The event fundamentally affected the concentrations of dissolved oxygen in the deep sea — enough to almost instantly shut down the accumulation of marine sediments known as banded iron formations, report Cannon and coauthor John F. Slack, also of the USGS in Reston.

Banded iron formations, massive deposits rich in iron oxides, have accumulated at several periods in Earth’s long-distant geological past, mostly when atmospheric concentrations of oxygen were low (SN: 6/20/09, p. 24).

One extended episode of banded iron formation (or BIF) buildup suddenly — and without an obvious explanation — ended about 1.85 billion years ago, says Cannon. Over a very short interval, he notes, “the environment shifted from one happily making banded iron to one that wasn’t.”

In northern Minnesota and other areas nearby, the formations lie directly underneath a thick layer of material only recently recognized as ejecta from the Sudbury impact. Mark Jirsa, a geologist with the Minnesota Geological Survey in St. Paul, was a member of the team that identified the ejecta layer. “We intuitively connected the Sudbury impact with the shutdown of BIF accumulation,” he says. “But now [Cannon and Slack] have come up with a model for how that might have happened.”

About 1.85 billion years ago, Earth’s now separate landmasses were joined in a single supercontinent. That also means there was one large ocean, says Cannon. Many scientists suggest that the object that slammed into Earth then — probably an asteroid abut 10 kilometers across — splashed down in that ocean, in waters about 1 kilometer deep on the shallow shelf surrounding the supercontinent. Models hint that the tsunami spawned by the event would have been 1 kilometer tall at the impact site and remained at least 100 meters tall about 3,000 kilometers away, Cannon adds.

Those immense waves and large underwater landslides triggered by the impact stirred the ocean, bringing oxygenated waters from the surface down to the ocean floor, the researchers propose. Sediments deposited on the seafloor before the impact, including BIFs, contained little if any iron in its Fe(III) form but were high in Fe(II), a sign that most parts of the ocean were oxygen-free. But marine sediments deposited after the impact included substantial amounts of Fe(III) but very little Fe(II) — and, therefore, sizable amounts of dissolved oxygen. The team’s analyses suggest that after the impact, dissolved iron spewed into the deepest parts of the ocean by hydrothermal vents would have reacted with oxygen within a day or so, thereby choking off most of the supply of Fe(II) to shallower waters where BIFs typically accumulated.

Interesting. Not the first time that it has been suggested that an asteroid stirred the oceanic pot. That was back in the early 1970s as an explanation for the Devonian Mass Extinctions: FF, iirc.

Thanx, Randy.

Microbial Mats in Archaen

2009-11-12T10:38:00.000-08:00

Palaeontology: Modern life in ancient mats

Michael M. Tice1
Top of page
Abstract

Microbial communities seem to have inhabited tidal sediments 2.9 billion years ago much as they do today — but what organisms were involved, and how they made their living, remain intriguing questions.

Establishing from fossil records how microbes and microbial ecosystems evolved is not an easy task: although 'microfossils' have been used to infer the presence and identity of microbes in particular environments1, 2, their simple shapes and comparative rarity limit what they can tell us. An alternative approach is to look for traces of products from communities of microorganisms3, 4. Research by Noffke et al.5, reported in Geobiology, illustrates this possibility. These authors have discovered evidence of 'microbial mats' in 2.9-billion-year-old sedimentary rocks from South Africa — a find that significantly augments the record of such structures from the Archaean eon, which ended 2.5 billion years ago.

Microbial mats are communities of microorganisms that grow in or on otherwise loose sediments, giving their substrate cohesiveness and tensile strength. Their consolidating effect means that they can produce a trace fossil record in sandstones and mudstones — even when no organic matter or microfossils are preserved. Structures that owe their existence to the stabilizing influence of mats can thus be important markers of ancient microbial ecosystems that would otherwise remain undetected.

Noffke et al.5 describe sandstones of the Sinqueni Formation, part of the Pongola Supergroup of eastern South Africa. These rocks were formed from sandy sediments deposited in a tidal environment 2.9 billion years ago, but several features preserved in them demonstrate a cohesiveness not seen in unconsolidated sand. Three structures seem to point particularly conclusively to an overlying microbial mat (Fig. 1). First, anomalously coherent, deformed chunks of sandy bed would have originated as chips of mat ripped up by energetic tidal currents and subsequently redeposited (Fig. 1a). Second, overfolded chips of rock (clasts) indicate where pieces of mat were rolled over on themselves, unexpected behaviour for layers of loosely associated sand grains (Fig. 1b). Third, oscillation cracks are present; these features would have been formed above the normal tidal range when pockets of gas periodically accumulated under, and escaped from, the mats (Fig. 1c). Such processes caused the mats' surfaces to expand and contract, forming cracked beds with upturned edges.

Just an fyi.

Oh, and bacterial/microbial mats are hardly strictly in the past. Ward strongly implies as much in The Medea Hypothesis. Next post on that relatively soon.

Japan Plans Solar Sail Called Ikaros

2009-11-12T08:27:00.000-08:00

Japan is planning to launch an interplanetary solar sail mission called Ikaros next May.

[...]

Ikaros stands for the Interplanetary Kite-craft Accelerated by Radiation Of the Sun. The name also harkens to the Greek mythological figure Icarus, who fashioned feathers and attempted to escape exile but flew too close to the sun.

The mission will launch next May on an H-2A rocket with the Akatsuki mission to Venus, according to the Japan Aerospace Exploration Agency.

The sqaure Ikaros sail, with a diagonal diameter of 66 feet, is covered with thin film solar cells to generate electricity. The spacecraft will spin up to about 20 rpm for stability during its mission.

Interesting...mmm. the cells on the sail make me wonder if this is truly a solar sail rather than a light weight solar panel, but...they say so, even in the acronym.

Watch Out Paleoenvironmental Modelers! Heeeeerrreeee's Hard Data!

2009-11-11T11:31:00.001-08:00

Earth's early ocean cooled more than a billion years earlier than thought: Stanford study

The scalding-hot sea that supposedly covered the early Earth may in fact never have existed, according to a new study by Stanford University researchers who analyzed isotope ratios in 3.4 billion-year-old ocean floor rocks. Their findings suggest that the early ocean was much more temperate and that, as a result, life likely diversified and spread across the globe much sooner in Earth's history than has been generally theorized.

It also means that the chemical composition of the ancient ocean was significantly different from today's ocean, which in turn may change interpretations of how the early atmosphere evolved, said Page Chamberlain, professor of environmental earth system science.

When rocks form on the ocean floor, they form in chemical equilibrium with the ocean water, incorporating similar proportions of different isotopes into the rock as are in the water. Isotopes are atoms of the same element that have different numbers of neutrons in the nucleus, giving them different masses. However, because the exact proportion of different isotopes that go into the rock is partly temperature dependent, the ratios in the rock provide critical clues into how warm the ocean was when the rock formed.

Previous studies of similarly aged rocks had looked only at oxygen isotope ratios, which suggested that in the Archean era (about 3.5 billion years ago), the ocean temperature was at least 55 degrees Celsius and may have been as high as 85 C, or 185 F. At a water temperature so perilously close to the boiling point, the only organisms that could have thrived would have been extremophiles – life forms adapted to extreme environments – such as the microbes that live in the intense heat of deep-sea hydrothermal vents or in hot springs such as at Yellowstone National Park.

But isotope ratios recorded in rocks on the ocean floor are also dependent on the chemical composition of the seawater in which those rocks formed, and the past studies assumed the composition of the ancient ocean was essentially what it is today [WB: *searing cry of soul destroying pain* with a blink tag!], which the Stanford study did not.

Using a relatively new approach, Michael Hren and Mike Tice, both Stanford graduate students at the time, analyzed hydrogen isotopes as well as oxygen isotopes in chert, a type of fine-grained sedimentary rock consisting primarily of quartz. The chert they studied was from an ancient deposit, formerly underwater but now on dry land in South Africa.

"By looking at both oxygen and hydrogen in these ancient rocks we were able to put some constraints on how different the ancient ocean composition may have been from today, and then use that composition to try to determine how hot the ancient ocean was," said Hren, who is the lead author of a paper describing the work being published online Nov. 12 by Nature. Tice and Chamberlain are coauthors.

Having data from isotope ratios of two elements allowed the researchers to calculate upper and lower bounds for the range of temperature and composition that could have given rise to the observed ratios. They determined that the ocean temperature could not have been more than 40 C (104 F) – the temperature of a hot tub – and may have been lower in some parts.

"This means that by 3.4 billion years ago, there were at least some places on the surface of the Earth where organisms that could not survive in these hot hydrothermal conditions could exist and thrive," Hren said. "It also suggests that the chemical composition of the ancient ocean was probably not identical to today, as previous studies assumed. It may have been quite different."

The researchers found that the ratio of the two stable isotopes of hydrogen in the chert was tilted away from the heavier of the isotopes – called deuterium.

"The ancient ocean had a lot more hydrogen in it, relative to deuterium, than modern oceans," Chamberlain said.

If the composition of the Archean ocean was significantly different from today, then the atmosphere must have been markedly different, too, owing to the ease with which gases move across the air-water boundary as the ocean and lower atmosphere strive to stay in a rough equilibrium.

That means that sometime during the past 3.4 billion years, the ocean had to lose a lot of hydrogen to the atmosphere to bring the hydrogen isotope ratio in seawater to where it is today. And since oxygen, not hydrogen, has built up in Earth's atmosphere over that same period of time, the atmosphere must have discharged a lot of hydrogen to the only other place it could go: space.

Hren said that some recent models of the early Earth atmosphere suggest that there may have been a prolonged period of hydrogen escaping to space, which would be consistent with the Stanford team's findings.

Oh hohoho! Talk about timing.

Also. Uh. DO NOT CUT N PASTE MODERN VALUES(*) INTO PALEOENVIRONMENTS! FOR CRYING OUT LOUD!

Update: Paper link.

* atmospheric contents, oceanic contents, continental mass, etc.

Congo's Jurassic Climate Was Arid

2009-11-10T15:29:00.001-08:00

The Congo Basin — with its massive, lush tropical rain forest — was far different 150 million to 200 million years ago. At that time Africa and South America were part of the single continent Gondwana. The Congo Basin was arid, with a small amount of seasonal rainfall, and few bushes or trees populated the landscape, according to a new geochemical analysis of rare ancient soils.

The geochemical analysis provides new data for the Jurassic period, when very little is known about Central Africa's paleoclimate, says Timothy S. Myers, a paleontology doctoral student in the Roy M. Huffington Department of Earth Sciences at Southern Methodist University in Dallas.

"There aren't a whole lot of terrestrial deposits from that time period preserved in Central Africa," Myers says. "Scientists have been looking at Africa's paleoclimate for some time, but data from this time period is unique."

There are several reasons for the scarcity of deposits: Ongoing armed conflict makes it difficult and challenging to retrieve them; and the thick vegetation, a humid climate and continual erosion prevent the preservation of ancient deposits, which would safeguard clues to Africa's paleoclimate.

Myers' research is based on a core sample drilled by a syndicate interested in the oil and mineral deposits in the Congo Basin. Myers accessed the sample — drilled from a depth of more than 2 kilometers — from the Royal Museum for Central Africa in Tervuren, Belgium, where it is housed. With the permission of the museum, he analyzed pieces of the core at the SMU Huffington Department of Earth Sciences Isotope Laboratory.

"I would love to look at an outcrop in the Congo," Myers says, "but I was happy to be able to do this."

The Samba borehole, as it's known, was drilled near the center of the Congo Basin. The Congo Basin today is a closed canopy tropical forest — the world's second largest after the Amazon. It's home to elephants, great apes, many species of birds and mammals, as well as the Congo River. Myers' results are consistent with data from other low paleolatitude, continental, Upper Jurassic deposits in Africa and with regional projections of paleoclimate generated by general circulation models, he says.

"It provides a good context for the vertebrate fossils found in Central Africa," Myers says. "At times, any indications of the paleoclimate are listed as an afterthought, because climate is more abstract. But it's important because it yields data about the ecological conditions. Climate determines the plant communities, and not just how many, but also the diversity of plants."

While there was no evidence of terrestrial vertebrates in the deposits that Myers studied, dinosaurs were present in Africa at the same time. Their fossils appear in places that were once closer to the coast, he says, and probably wetter and more hospitable.

The Belgium samples yielded good evidence of the paleoclimate. Myers found minerals indicative of an extremely arid climate typical of a marshy, saline environment. With the Congo Basin at the center of Gondwana, humid marine air from the coasts would have lost much of its moisture content by the time it reached the interior of the massive continent.

"There probably wouldn't have been a whole lot of trees; more scrubby kinds of plants," Myers says.

The clay minerals that form in soils have an isotopic composition related to that of the local rainfall and shallow groundwater. The difference in isotopic composition between these waters and the clay minerals is a function of surface temperature, he says. By measuring the oxygen and hydrogen isotopic values of the clays in the soils, researchers can estimate the temperature at which the clays formed. For more information see www.smuresearch.com.

No time to comment.

Planetary Society Trying Solar Sail Again

2009-11-10T10:49:00.000-08:00

The Planetary Society announced today that an anonymous donor has put upone million dollars to help us get a solar sail in flight. That money will kick-start our ambitious new LightSail program, a series of three increasingly large solar sails that mark individual steps in the path toward viable solar sail flight.

LightSail-1 will start with the same basic goal that Cosmos-1 had: to demonstrate that sunlight alone can propel a spacecraft in Earth orbit. But its design is quite different: it will be built of a stack of three cubesats, each only ten centimeters on a side, or one liter in volume. One cubesat will house the electronics, and the other two the ultrathin Mylar sails, four of them, together comprising 32 square meters of sail area. It'll launch to an orbit more than 800 kilometers above Earth, out of reach of the atmosphere.

*sighs*

I wish I had million dollar donors.

I actually love solar sails more than rockets, but there's more of a market for rockets than solar sails.

A Japanese TV Spot on the ShinShin Stealth Fighter Prototype

2009-11-10T07:45:00.000-08:00

Hat tip: Dew Line.

Forgive me, but the style feels very 1980s for some reason for me.

NERSC's New System: Announcing Carver

2009-11-09T10:38:00.000-08:00

Carver: IBM iDataPlex

NERSC's next medium-sized scientific computing system will be an IBM iDataPlex Linux cluster. The IBM system, selected in a competitive procurement, provides excellent performance, good energy efficiency per flop, and a familiar environment for mid-range parallel applications. It is intended to replace Bassi and Jacquard.

The system will be named after the American scientist George Washington Carver.

410 nodes with dual quad core Nehalems. IB interconnect. More than 10 TB of memory. 1.2 PB of disk. 34.2 TFlops peak. Link in title, as always.

Insect Pollination Before Angiosperms

2009-11-09T10:05:00.000-08:00

A Probable Pollination Mode Before Angiosperms: Eurasian, Long-Proboscid Scorpionflies

1. Dong Ren (a)
2. Conrad C. Labandeira (b,c,*)
3. Jorge A. Santiago-Blay (b,d)
4. Alexandr Rasnitsyn (e,f)
5. ChungKun Shih (a)
6. Alexei Bashkuev (e)
7. M. Amelia V. Logan (g)
8. Carol L. Hotton (b,h)
9. David Dilcher (b,i)

a College of Life Sciences, Capital Normal University, Beijing 100048, China.

b Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA.

c Department of Entomology, University of Maryland, College Park, MD 20742, USA.

d Department of Biology, Gallaudet University, Washington, DC 20003, USA.

e Paleontological Institute, Russian Academy of Sciences, Moscow 117997, Russia.

f Department of Palaeontology, Natural History Museum, London SW7 5BD, UK.

g Department of Mineral Sciences, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA.

h National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20892, USA.

i Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA.

* To whom correspondence should be addressed. E-mail: labandec@si.edu

Abstract:

The head and mouthpart structures of 11 species of Eurasian scorpionflies represent three extinct and closely related families during a 62-million-year interval from the late Middle Jurassic to the late Early Cretaceous. These taxa had elongate, siphonate (tubular) proboscides and fed on ovular secretions of extinct gymnosperms. Five potential ovulate host-plant taxa co-occur with these insects: a seed fern, conifer, ginkgoopsid, pentoxylalean, and gnetalean. The presence of scorpionfly taxa suggests that siphonate proboscides fed on gymnosperm pollination drops and likely engaged in pollination mutualisms with gymnosperms during the mid-Mesozoic, long before the similar and independent coevolution of nectar-feeding flies, moths, and beetles on angiosperms. All three scorpionfly families became extinct during the later Early Cretaceous, coincident with global gymnosperm-to-angiosperm turnover.

Interesting...

Arctic Traps 25% of the World's Carbon

2009-11-09T10:03:00.000-08:00

The arctic could potentially alter the Earth’s climate by becoming a possible source of global atmospheric carbon dioxide. The arctic now traps or absorbs up to 25 percent of this gas but climate change could alter that amount, according to a study published in the November,2009 issue of Ecological Monographs.

In their review paper, David McGuire of the U.S. Geological Survey and the University of Alaska at Fairbanks and his colleagues show that the Arctic has been a carbon sink since the end of the last Ice Age, which has recently accounted for between zero and 25 percent, or up to about 800 million metric tons, of the global carbon sink. On average, says McGuire, the Arctic accounts for 10-15 percent of the Earth’s carbon sink. But the rapid rate of climate change in the Arctic – about twice that of lower latitudes – could eliminate the sink and instead, possibly make the Arctic a source of carbon dioxide.

mmm. Toasty.

Hrm. Kickstarter invite? Anyone?

2009-11-06T18:42:00.000-08:00

After Tom's suggestion, I thought trying kickstarter might be a good idea to give it a try. However, given its requirement to have an invite to start a project....would there happen to be someone with an available invite?

w baird at team phoenicia dot org.

thanx.

Dust Plumes Over the Med

2009-11-06T07:59:00.001-08:00