Illness may have killed mighty T-Rex

Mighty Tyrannosaurus Rex may have fallen to trench mouth, paleontologists report Tuesday. In a look at the famous T-Rex, Sue, and her kin, a team led by Ewan Wolff of the University of Wisconsin-Madison and Steven Salisbury of Australia's University of Queensland, pin the blame on an avian ailment for ulcers in the jaws of the King of Dinosaurs. The parasitic microbe bores holes in the jaws of falcons and hawks in patterns identical to holes seen in T-Rex fossils, the team reports in the journal PLoS One.

Paleontologists had earlier suggested Sue suffered from a different infection seen today in cattle. Others said she might have been bitten by other tyrannosaurs, the most common source of trauma seen on their fossilized bones (with head bites found on 44% of adults).

However the cattle infection doesn't afflict non-mammals, and T. Rex bites are distinctive and unlike the jaw holes seen in Sue and her fellows. Instead, "these abnormalities have a strong resemblance to those lesions resulting from an infectious disease known to occur in modern birds called trichomonosis," says the study. "Nearly 15% of the 61 tyrannosaurid individuals examined during this study exhibited trichomonosis-type lesions on the mandible."

Tyrannosaurs may have acquired the disease by eating each other, the researchers suggest. Given their shared heritage with birds, likely suffered the same way as hawks and falcons today, enduring debilitating throat damage. ""The lesions we observe on Sue suggest a very advanced stage of the disease and may even have been the cause of her demise," says Wolff, in a statement. "It is a distinct possibility as it would have made feeding incredibly difficult. You have to have a viable pharynx. Without that, you won't make it for very long, no matter how powerful you are."

By Dan Vergano
Photo: An artist's rendering of a T. rex suffering from a trichomonosis-like disease, a parasitic infection caused by a protozoan, a single-celled organism that infects the mouth and throat and may have caused the animal to starve to death. (Chris Glen, University of Queensland)

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NASA spacecraft approaches Mercury

NASA's MESSENGER spacecraft has finished it 12,000 mile-per-hour flyby of Mercury, losing some data to a communications glitch, but successfully setting its course for a 2011 final rendezvous with the planet. Never seen before, a volcanic pit, a double crater and smooth plains revealed themselves on the spacecraft's 142-mile high passage over Mercury on Monday.

“This third and final flyby was MESSENGER’s last opportunity to use the gravity of Mercury to meet the demands of the cruise trajectory without using the probe’s limited supply of on-board propellant,” says the MESSENGER team's Eric Finnegan of the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md. On its present orbit, MESSENGER will be gravitationally captured by Mercury in March of 2011.

The flyby completed the mapping of most of Mercury from space started in two earlier MESSENGER flybys. After a "carrier" signal was dropped by the spacecraft during the flyby, it went into "safe" mode, halting some of its observations, but keeping intact already-recorded data.

Even with any missing observations, "we are on course to Mercury orbit insertion less than 18 months from now, so we know that we will be returning to Mercury and will be able to observe the innermost planet in exquisite detail," said mission principal investigator Sean Solomon of the Carnegie Institution of Washington.

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Panel: Self-policing best defense against insider bioterrorism attacks

The best defense against insider bioterrorist attacks is "a culture of trust and responsibility in the laboratory," says a science panel report Wednesday. The National Research Council report, "Responsible Research with Biological Select Agents and Toxins," concludes that developing strong ethics against misuse of microbes matters as much, or more, to forestall attacks like the 2001 anthrax mailings that killed 5 people and sickened 17 others.

"The goal should be that individuals watch out for each other and take responsibility for their own performance and that of others," says a statement from the report panel, headed by Rita Colwell of the University of Maryland.

Some 80 "select agents", microbes and toxins ranging from ricin to plague, require registration with federal authorities. Security Risk Assessment screening checks more than 20 criminal, immigration, and terrorist databases to qualify researchers and is appropriate, the panel says.

However, "because biological select agents can replicate, an undue reliance on accounting techniques, such as counting vials, to monitor whether a biological agent has been removed from a laboratory offers a false sense of security and is counterproductive." Instead, lab security must heavily involve researchers themselves in a culture of safety to forestall accidents and malicious use of microbes.

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Before Lucy came Ardi, new earliest hominid found

WASHINGTON – The story of humankind is reaching back another million years as scientists learn more about "Ardi," a hominid who lived 4.4 million years ago in what is now Ethiopia. The 110-pound, 4-foot female roamed forests a million years before the famous Lucy, long studied as the earliest skeleton of a human ancestor.

This older skeleton reverses the common wisdom of human evolution, said anthropologist C. Owen Lovejoy of Kent State University.

Rather than humans evolving from an ancient chimp-like creature, the new find provides evidence that chimps and humans evolved from some long-ago common ancestor — but each evolved and changed separately along the way.

"This is not that common ancestor, but it's the closest we have ever been able to come," said Tim White, director of the Human Evolution Research Center at the University of California, Berkeley.

The lines that evolved into modern humans and living apes probably shared an ancestor 6 million to 7 million years ago, White said in a telephone interview.

But Ardi has many traits that do not appear in modern-day African apes, leading to the conclusion that the apes evolved extensively since we shared that last common ancestor.

A study of Ardi, under way since the first bones were discovered in 1994, indicates the species lived in the woodlands and could climb on all fours along tree branches, but the development of their arms and legs indicates they didn't spend much time in the trees. And they could walk upright, on two legs, when on the ground.

Formally dubbed Ardipithecus ramidus — which means root of the ground ape — the find is detailed in 11 research papers published Thursday by the journal Science.

"This is one of the most important discoveries for the study of human evolution," said David Pilbeam, curator of paleoanthropology at Harvard's Peabody Museum of Archaeology and Ethnology.

"It is relatively complete in that it preserves head, hands, feet and some critical parts in between. It represents a genus plausibly ancestral to Australopithecus — itself ancestral to our genus Homo," said Pilbeam, who was not part of the research teams.

Scientists assembled the skeleton from 125 pieces.

Lucy, also found in Africa, thrived a million years after Ardi and was of the more human-like genus Australopithecus.

"In Ardipithecus we have an unspecialized form that hasn't evolved very far in the direction of Australopithecus. So when you go from head to toe, you're seeing a mosaic creature that is neither chimpanzee, nor is it human. It is Ardipithecus," said White.

White noted that Charles Darwin, whose research in the 19th century paved the way for the science of evolution, was cautious about the last common ancestor between humans and apes.

"Darwin said we have to be really careful. The only way we're really going to know what this last common ancestor looked like is to go and find it. Well, at 4.4 million years ago we found something pretty close to it," White said. "And, just like Darwin appreciated, evolution of the ape lineages and the human lineage has been going on independently since the time those lines split, since that last common ancestor we shared."

Some details about Ardi in the collection of papers:

• Ardi was found in Ethiopia's Afar Rift, where many fossils of ancient plants and animals have been discovered. Findings near the skeleton indicate that at the time it was a wooded environment. Fossils of 29 species of birds and 20 species of small mammals were found at the site.

• Geologist Giday WoldeGabriel of Los Alamos National Laboratory was able to use volcanic layers above and below the fossil to date it to 4.4 million years ago.

• Ardi's upper canine teeth are more like the stubby ones of modern humans than the long, sharp, pointed ones of male chimpanzees and most other primates. An analysis of the tooth enamel suggests a diverse diet, including fruit and other woodland-based foods such as nuts and leaves.

• Paleoanthropologist Gen Suwa of the University of Tokyo reported that Ardi's face had a projecting muzzle, giving her an ape-like appearance. But it didn't thrust forward quite as much as the lower faces of modern African apes do. Some features of her skull, such as the ridge above the eye socket, are quite different from those of chimpanzees. The details of the bottom of the skull, where nerves and blood vessels enter the brain, indicate that Ardi's brain was positioned in a way similar to modern humans, possibly suggesting that the hominid brain may have been already poised to expand areas involving aspects of visual and spatial perception.

• Ardi's hand and wrist were a mix of primitive traits and a few new ones, but they don't include the hallmark traits of the modern tree-hanging, knuckle-walking chimps and gorillas. She had relatively short palms and fingers which were flexible, allowing her to support her body weight on her palms while moving along tree branches, but she had to be a careful climber because she lacked the anatomical features that allow modern-day African apes to swing, hang and easily move through the trees.

• The pelvis and hip show the gluteal muscles were positioned so she could walk upright.

• Her feet were rigid enough for walking but still had a grasping big toe for use in climbing.

The research was funded by the National Science Foundation, the Institute of Geophysics and Planetary Physics of the University of California, Los Alamos National Laboratory, the Japan Society for the Promotion of Science and others.

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30-year-old mystery of planetary nebulae solved

Astronomers have resolved a 30-year-old argument, ruling out a one-size-fits-all mechanism for shaping some of the most beautiful objects in space -- the planetary nebulae.

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Planetary nebulae have nothing to do with planets, but are enlarged glowing objects that is stars late in their lives which have shed much of their gas into space. Some appear as round blobs and can look like an eye, an ant or an hourglass. The question is, what forms these shapes? There have been two ideas. One is that a planetary nebula arises from a single star in the late stage of its life. The second idea is two stars are involved with the aged one providing the gas. Now, an international team, led by Brent Miszalski of the Anglo-Australian Observatory, has clearly ruled it out as a general mechanism for shaping majority of planetary nebulae, the Astronomy & Astrophysics journal reported. In their research, the team drew on a number of catalogues of planetary nebulae, particularly those derived from the Macquarie/AAO/Strasbourg H-alpha surveys, to amass a collection of hundreds of possible central stars in nebulae. Using the OGLE-III photometric survey, they then looked for periodic variability in the light of the central star, which could be a sign that the central star was, in fact, a binary two stars orbiting each other. After refining their sample by knocking out dubious objects, the team was left with a set of about 300 planetary nebulae, of which 21 showed evidence for a central binary. This more than doubled the number of planetary nebulae known to have central binaries. The astronomers concluded that close binaries occur in 10-20 per cent of planetary nebulae. Their figure agrees with, and provides the first independent support for, an estimate of 10-15 per cent published in 2000. The team also found that the periods of the detected binaries were much shorter than had been predicted. 'Why, we don't know yet. All we can say is that the existing models don't well match what we've found. 'Binarity is not a precondition for the formation of planetary nebulae and close binaries do not play a dominant role in the shaping of nebular morphologies,' Miszalski said.

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Harmonise the Efforts of African Scientists

ADDIS ABABA, Sep 24 (IPS) - As many as 100 million people in Africa suffer from schistosomiasis, a chronic illness caused by a parasite associated with freshwater snails. The schistosoma flatworm causes a debilitating illness that can damage internal organs, and stunt growth and cognitive development of children.

The harmful socioeconomic impacts of the condition are second only to malaria, yet it can be controlled with a single annual dose of the drug praziquantel.

Sanaa Botros, professor of pharmacology at Egypt's ministry of scientific research, is one of the leading researchers into the treatment of schistosomiasis and other tropical diseases.

She was one of five women honoured recently by the African Union for their scientific achievements.

IPS: What are some of the results of your research?

SANAA BOTROS: (For a long time in Egypt) the only available drug for schistosoma was imported. A local company formulated a drug. I did the comparison with the imported one and proved that they have equal curative effect. Now we are using the local one all over the country. This has saved the country a lot of money.

I believe when you can recommend to the government that the medication produced at home is equal to the imported one in treating the disease, that is quite an achievement.

Some of my other research has been on one of the newly introduced drugs for schistosomiasis whose producers claimed 98 to 100 percent cure.

When I studied the drug, it was defective. Based on my report, the government stopped the distribution of this drug and another African country reversed its plan to buy this drug.

IPS: You are a member of the African Network for Drugs and Diagnostic Innovations (ANDI). What's the purpose of this network?

SB: When we started this work, we found great capacity scattered with no linkages.

I may be doing good work (on schistosomiasis) in Egypt but the one in South Africa does not know anything about me or the things I do. We have very good work in countries like Nigeria and Guinea concentrating on malaria. But these efforts are not harmonised.

To harmonise the efforts is be a very important point for African scientists.

IPS: Some say the African Union has neglected the area of scientific research and technology. Do you share that view?

SB: I actually believe the attitude is changing very much. I can see that from the ANDI. We have been working for nearly a year and we are now formulating a business plan for the execution. So I can say that there is a sort of realisation that unless we push science and technology at the level of the AU, we cannot achieve development.

IPS: What do you think have been the consequences of the low priority placed on science to this point?

SB: You cannot develop unless you focus on research, science and technology.

IPS: How do you see the role of women in Africa in the area of scientific research?

SB: In my institute as well as all Egypt, we have a very high percentage of women scientists. But it does not mean everything is rosy.

We have women councillors, women police officers, women working in different fields. But we have problems with women's representation in parliament.

At the Africa level, I believe we women have to push a lot further to ensure our roles still increase. I know a lot of non-governmental organisations are working on women's empowerment in Africa. But we do not form enough linkages among different countries.

IPS: When was the most challenging period in your career?

SB: It was when I started as a young scientist, immediately after I did my PhD. People did not know me and when I asked them to sponsor publication of my research, they rejected me saying, "Who is Sanaa Botros from Egypt?"

I think my being an African and a woman partially contributed.

IPS: What does the prize from the African Union mean to you?

SB: It means a lot because the appreciation and recognition from the continent means Africa is watching me and that initiates me to do more and realize the continent expects more from me.

When you are a pharmacologist staying in the labs, you do not feel rewarded because you do not see the patients getting cured like clinicians do. This is our reward.

IPS: If girls from rural villages or poor urban neighbourhoods somewhere in Africa sought your advice on how to become like you, what would you tell them?

SB: Do anything to be educated. In my childhood and youth, I fortunately had very good teachers who were very enthusiastic about my interests and that helped me a lot in shaping my current situation.

So I believe teachers are key personalities who determine the future of African girls.

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It's not lunacy, probes find water in moon dirt

WASHINGTON — The moon isn't the dry dull place it seems. Traces of water lurk in the dirt unseen.

Three different space probes found the chemical signature of water all over the moon's surface, surprising the scientists who at first doubted the unexpected measurement until it was confirmed independently and repeatedly.

It's not enough moisture to foster homegrown life on the moon. But if processed in mass quantities, it might provide resources — drinking water and rocket fuel — for future moon-dwellers, scientists say. The water comes and goes during the lunar day.

It's not a lot of water. If you took a two-liter soda bottle of lunar dirt, there would probably be a medicine dropperful of water in it, said University of Maryland astronomer Jessica Sunshine, one of the scientists who discovered the water. Another way to think of it is if you want a drink of water, it would take a baseball diamond's worth of dirt, said team leader Carle Pieters of Brown University.

"It's sort of just sticking on the surface," Sunshine said. "We always think of the moon as dead and this is sort of a dynamic process that's going on."

The discovery, with three studies bring published in the journal Science on Thursday and a NASA briefing, could refocus interest in the moon. The appeal of the moon waned after astronauts visited 40 years ago and called it "magnificent desolation."

The announcement comes two weeks before a NASA probe purposely smashes near the moon's south pole to see if it can kick up buried ice. Over the last decade, astronomers have found some signs of underground ice on the moon's poles. But this latest discovery is quite different. It finds unexpected and pervasive water clinging to the surface of soil, not absorbed into it.

"It is drier than any desert we have here," Sunshine said.

The water was spotted by spacecraft that either circled the moon or flew by. All three ships used the same type of instrument that looked at the absorption of a specific wavelength of light that is the chemical signature of only two molecules: water and hydroxyl. Hydroxyl is one atom of hydrogen with one atom of oxygen, instead of two hydrogen atoms in water.

Because of the timing during the daylight when some of that wavelength disappears and some doesn't, it shows that both hydroxyl and water are present, Sunshine said.

This light wavelength was first discovered by an instrument on the Indian lunar satellite Chandrayaan-1, which stopped operating last month. Scientists initially figured something was wrong with the instrument because everyone knew the moon did not have a drop of water on the surface, Pieters said.

"We argued literally for months amongst ourselves to find out where the problem was," Pieters said. Sunshine, who was on the team, had a similar instrument on NASA's Deep Impact probe, headed for a comet but swinging by the moon in June. So Deep Impact looked for the water-hydroxyl signature — and found it.

Scientists also looked back at the records of NASA's Cassini probe, which is circling Saturn. It has the same type instrument and whizzed by the moon ten years ago. Sure enough, it had found the same thing.

The chance that three different instruments malfunctioned in the same way on three different spaceships is almost zilch, so this confirms that it's water and hydroxyl, Pieters said.

"There's just no question that it's there," Pieters said. "It's unequivocal."

Scientists testing lunar samples returned to Earth by astronauts did find traces of water, but they had figured it was contamination from moisture in Earth air, Pieters said.

Three scientists who were not part of the team of discoverers said the conclusion makes sense, with Arizona State University's Ron Greeley using the same word as Pieters: unequivocal.

Lunar and Planetary Institute senior scientist Paul Spudis called it exciting and said it raises the logical question: Where did that water come from?

Pieters figures there are three possibilities: It came from comets or asteroids that crashed into the moon, those crashes freed up trapped water from below the surface, or the solar wind carries hydrogen atoms that binds with oxygen in the dirt. That final possibility is the one that Sunshine and Pieters both prefer.

If it is the solar wind, that also means that other places without atmosphere in our solar system, such as Mercury or asteroids, can also have bits of water, Sunshine said.

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