Eideard

The tip of a girl’s 40,000-year-old pinky finger found in a cold Siberian cave, paired with faster and cheaper genetic sequencing technology, is helping scientists draw a surprisingly complex new picture of human origins.

The new view is fast supplanting the traditional idea that modern humans triumphantly marched out of Africa about 50,000 years ago, replacing all other types that had gone before.

Instead, the genetic analysis shows, modern humans encountered and bred with at least two groups of ancient humans in relatively recent times: the Neanderthals, who lived in Europe and Asia, dying out roughly 30,000 years ago, and a mysterious group known as the Denisovans, who lived in Asia and most likely vanished around the same time.

Their DNA lives on in us even though they are extinct. “In a sense, we are a hybrid species,” Chris Stringer, a paleoanthropologist who is the research leader in human origins at the Natural History Museum in London, said in an interview.

The Denisovans were first described a year ago in a groundbreaking paper in the journal Nature made possible by genetic sequencing of the girl’s pinky bone and of an oddly shaped molar from a young adult. Those findings have unleashed a spate of new analyses.

Scientists are trying to envision the ancient couplings and their consequences: when and where they took place, how they happened, how many produced offspring and what effect the archaic genes have on humans today…

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Always good for what ails you.

Click twice on the graphic to seriously enlarge

Joe Cohen started work on malaria vaccine at GSK in 1987

Millions of small children’s lives could be saved by a new vaccine which has been shown to halve the risk of malaria in the first large-scale trials across seven African countries.

The long-awaited results of the largest-ever malaria vaccine study, involving 15,460 babies and small children, show that it could massively reduce the impact of the much-feared killer disease. Malaria takes nearly 800,000 lives every year – most of them small children under the age of five. It damages many more.

The vaccine has been in development for two decades – the brainchild of scientists at the UK drug company GlaxoSmithKline, which has promised to sell it at no more than a fraction over cost-price, with the excess being ploughed back into further tropical disease research…

GSK’s chief executive, Andrew Witty told the Guardian he was thrilled for the scientists who were thought by many of their peers to be attempting the impossible when they started work on a vaccine 25 years ago.

“When the team was first shown the data, quite a number of them broke down in tears,” he said. “It was the emotion of what they had achieved – the first vaccine against a parasitic form of infection. They were overwhelmed. It says something about the amount of heart that has gone into this project…”

Witty says he is exhorting everybody involved in the vaccine’s production to pare their costs to the bone. “We are absolutely dedicated to making it as low as possible,” he said.

Bravo.

Damned few corporations – especially in pharmaceuticals – are willing to work on solutions for low-profit markets, low-return investments. GSK and Mr. Witty deserve special credit for joining forces with WHO and the Gates Foundation.

Our species may have bred with a now extinct lineage of humanity before leaving Africa, scientists say.

Although we modern humans are now the only surviving lineage of humanity, others once roamed the Earth, making their way out of Africa before our species did, including the familiar Neanderthals in West Asia and Europe and the newfound Denisovans in East Asia. Genetic analysis of fossils of these extinct lineages has revealed they once interbred with modern humans, unions that may have endowed our lineage with mutations that protected them as we began expanding across the world about 65,000 years ago.

Now researchers analyzing the human genome find evidence that our species hybridized with a hitherto unknown human lineage even before leaving Africa, with approximately 2 percent of contemporary African DNA perhaps coming from this lineage. In comparison, recent estimates suggest that Neanderthal DNA makes up 1 percent to 4 percent of modern Eurasian genomes and Denisovan DNA makes up 4 percent to 6 percent of modern Melanesian genomes.

“We need to modify the standard model of human origins in which a single population transitioned to the anatomically modern state in isolation — a garden of Eden somewhere in Africa — and replaced all other archaic forms both within Africa and outside Africa without interbreeding,” researcher Michael Hammer, a population geneticist at the University of Arizona in Tucson, told LiveScience. “We now need to consider models in which gene flow occurred over time…”

“We think there were probably thousands of interbreeding events,” Hammer said. “It happened relatively extensively and regularly.”

I don’t think the “extensive and regular” part is a surprise either. It may upset some boring, straight-laced and narrow-minded pundits; but, evolution doesn’t pay any attention to ideology.

If your heritage is non-African, you are part Neanderthal, according to a new study in the July issue of Molecular Biology and Evolution…This latest research confirms earlier findings.

Damian Labuda of the University of Montreal’s Department of Pediatrics and the CHU Sainte-Justine Research Center conducted the study with his colleagues. They determined some of the human X chromosome originates from Neanderthals, but only in people of non-African heritage.

“This confirms recent findings suggesting that the two populations interbred,” Labuda was quoted as saying in a press release. His team believes most, if not all, of the interbreeding took place in the Middle East, while modern humans were migrating out of Africa and spreading to other regions…

Neanderthals possessed the gene for language and had sophisticated music, art and tool craftsmanship skills, so they must have not been all that unattractive to modern humans at the time.

“In addition, because our methods were totally independent of Neanderthal material, we can also conclude that previous results were not influenced by contaminating artifacts,” Labuda said.

This work goes back to nearly a decade ago, when Labuda and his colleagues identified a piece of DNA, called a haplotype, in the human X chromosome that seemed different. They questioned its origins…

David Reich, a Harvard Medical School geneticist, added, “Dr. Labuda and his colleagues were the first to identify a genetic variation in non-Africans that was likely to have come from an archaic population. This was done entirely without the Neanderthal genome sequence, but in light of the Neanderthal sequence, it is now clear that they were absolutely right!”

The modern human/Neanderthal combo likely benefitted our species, enabling it to survive in harsh, cold regions that Neanderthals previously had adapted to.

“Variability is very important for long-term survival of a species,” Labuda concluded. “Every addition to the genome can be enriching.”

Someone should explain that to the populist puritans still marching to the George Wallace drum from decades past. Meanwhile -

The admixture and uniting of Neanderthal and Cro-Magnon streams in comparatively modern hominids is something that many students of ethnology felt would be proved sooner or later. Some thought reluctance to accept the work offered by Professor Labuda was prompted more by hopes of “purity” than reality. Folks have to understand that human beings have sex with just about anyone, anytime, anywhere – given the opportunity.

Kinshasha strings

Josephine Mpongo of the the Kimbanguiste Symphony Orchestra practises the cello in the group’s rehearsal space. Andrew McConnell’s picture won the best of show prize in the US National Press Photographers Association’s 2011 photojournalism contest.

The Biblical story of Lazarus is happening again in Africa. At least it looks that way.

One moment, men, women and children suffering from AIDS are lying at death’s door, barely able to move, open their eyes, or speak. Then a few days or weeks later, they are walking, talking, laughing; truly appearing to have come back from the dead.

This astonishing transformation has been repeated all over the continent thousands of times over the past decade. And, since 2003, America has been helping to pay for it.

But a budget-slashing effort in Congress this year threatens to bring much of that progress to a sudden and catastrophic halt.

“He often talked about ‘To whom much is given, much is required,’ ” said Michael Gerson, of the sponsor of the plan. “There was a motivation here of what America should do and be; that we should be a source of hope but also a kind of conscience motivation here, very much rooted in his faith.”

The “he” in question, was President George W. Bush.

In 2003, Bush started the President’s Emergency Plan for AIDS Relief, or PEPFAR — an unprecedented, $3-billion a year program to help the world fight AIDS and has resulted in an 80-fold increase in the number of Africans receiving life-saving AIDS treatments since the program began…

When PEPFAR began only 50,000 people in Sub-Saharan Africa were on AIDS drugs; today, it’s 4 million. The cost has been driven down to 40 cents per person, per day. And in a region with more than a million AIDS deaths annually, and 16 million AIDS orphans, keeping parents alive can keep families, communities, whole countries afloat, according to the film.

Gerson concedes many Americans just don’t know about the good PEPFAR has done, but he said, “I will tell you, people in Africa know that Americans were responsible; know what was done to save these societies; and they are deeply grateful.”

And they will know that it is Americans who stopped helping – if Congress, the Kool Aid Party members who especially hate aiding foreigners along with ideologues like Ron Paul succeed in crushing the PEPFAR Program.

The Ugly American is alive and well in Washington, DC – even if he doesn’t place his well-shod feet directly on the necks of poor people in Africa, Asia and Latin America, anymore. Just as people in countries around the world remember who bombed their villages, propped up dictators with American arms and aid – they will not forget which country brought back millions of people from the edge of a terrible death only to let them slide once again into the valley of death.

The first humans to reach Europe may have found it a ghost world. Carbon-dated Neanderthal remains from the foothills of the Caucasus Mountains suggest that the archaic species had died out before modern humans arrived.

The remains are almost 10,000 years older than expected. They come from just one cave in western Russia, called Mezmaiskaya, but bones at other Neanderthal sites farther west could also turn out to be more ancient than previously thought, thanks to a precise carbon-dating technique, says Thomas Higham, a palaeoanthropologist at the University of Oxford, UK, and a co-author of a study published this week in the Proceedings of the National Academy of Sciences.

The implication, says Higham’s team, is that Neanderthals and humans might never have met in Europe. However, the Neanderthal genome, decoded last year, hints that the ancestors of all humans, except those from Africa, interbred with Neanderthals somewhere. Perhaps humans departing Africa encountered resident Neanderthals in the Middle East.

“DNA results show that there was admixture probably at some stage in our human ancestry, but it more than likely happened quite a long time before humans arrived in Europe,” says Ron Pinhasi, an archaeologist at University College Cork in Ireland, who is lead author of the latest study. “I don’t believe there were regions where Neanderthals were living next to modern humans. I just don’t find it very feasible,” he adds…

Previous excavations had suggested that the most recent Neanderthals at Mezmaiskaya died around 33,000 years ago. But using the most up-to-date dating techniques, Pinhasi and his team dated the remains of two Neanderthal infants from the site to around 40,000 years ago. The infants’ bones were found above the cave’s other Neanderthal remains, so they must be the most recent, says Higham.

He is now re-dating other Neanderthal sites, and expects those dates to creep upwards, too. “My gut feeling would be that probably the latest Neanderthals and the earliest modern humans may have overlapped for a bit, but not for too much,” says Higham.

David Reich, a geneticist at Harvard Medical School in Boston, Massachusetts, says that Higham’s conclusion fits with his own team’s discovery that all contemporary humans, except those who trace their ancestry to Africa, owe about 1–4% of their DNA to interbreeding between humans and Neanderthals. Reich’s team did not find any proof that Neanderthals ever mated with the ancestors of modern Europeans specifically.

Yet Reich says that new, more sensitive methods for detecting interbreeding, as well as genome sequences from late Neanderthals could change that conclusion. “Absence of evidence isn’t evidence of absence,” he says.

Step by step, new methods, new techniques make science more precise. If you have learned to found knowledge and decision-making upon verifiable evidence, you stand in good stead to adapt to changing times, a changing view of history and prehistory.

A spectacular haul of stone tools discovered beneath a collapsed rock shelter in southern Arabia has forced a major rethink of the story of human migration out of Africa. The collection of hand axes and other tools shaped to cut, pierce and scrape bear the hallmarks of early human workmanship, but date from 125,000 years ago, around 55,000 years before our ancestors were thought to have left the continent.

The artefacts, uncovered in the United Arab Emirates, point to a much earlier dispersal of ancient humans, who probably cut across from the Horn of Africa to the Arabian peninsula via a shallow channel in the Red Sea that became passable at the end of an ice age. Once established, these early pioneers may have pushed on across the Persian Gulf, perhaps reaching as far as India, Indonesia and eventually Australia.

Michael Petraglia, an archaeologist at Oxford University who was not involved in the work, told the Science journal: “This is really quite spectacular. It breaks the back of the current consensus view.”

1. Pretty consistent with human spirit to have early adopters.

2. Perfectly consistent for scientists to be open to further examination of existing theories. It’s part of what peer review is about.

Anatomically modern humans – those that resemble people alive today – evolved in Africa about 200,000 years ago. Until now, most archaeological evidence has supported an exodus from Africa, or several waves of migration, along the Mediterranean coast or the Arabian shoreline between 80,000 and 60,000 years ago…

The stones, a form of silica-rich rock called chert, were dated by Simon Armitage, a researcher at Royal Holloway, University of London, using a technique that measured how long sand grains around the artefacts had been buried…

The discovery has sparked debate among archaeologists, some of whom say much stronger evidence is needed to back up the researchers’ claims. “I’m totally unpersuaded,” Paul Mellars, an archaeologist at Cambridge University, told Science. “There’s not a scrap of evidence here that these were made by modern humans, nor that they came from Africa.”

Chris Stringer, a palaeontologist at the Natural History Museum in London, said: “The region of Arabia has been terra incognita in trying to map the dispersal of modern humans from Africa during the last 120,000 years, leading to much theorising in the face of few data.

“Despite the confounding lack of diagnostic fossil evidence, this archaeological work provides important clues that early modern humans might have dispersed from Africa across Arabia, as far as the Straits of Hormuz, by 120,000 years ago.”

The debate will continue. More will be learned. It is the nature of good science.

RTFA and reflect upon the first bits of information coming from the research.

Five years ago, Bill Gates made an extraordinary offer: he invited the world’s scientists to submit ideas for tackling the biggest problems in global health, including the lack of vaccines for AIDS and malaria, the fact that most vaccines must be kept refrigerated and be delivered by needles, the fact that many tropical crops like cassavas and bananas had little nutrition, and so on.

No idea was too radical, he said, and what he called the Grand Challenges in Global Health would pursue paths that the National Institutes of Health and other grant makers could not.

About 1,600 proposals came in, and the top 43 were so promising that the Bill & Melinda Gates Foundation made $450 million in five-year grants — more than double what he originally planned to give.

Now the five years are up, and the foundation recently brought all the scientists to Seattle to assess the results and decide who will get further funding.

In an interview, Mr. Gates sounded somewhat chastened, saying several times, “We were naïve when we began…”

He underestimated, he said, how long it takes to get a new product from the lab to clinical trials to low-cost manufacturing to acceptance in third-world countries…

That little won’t buy a breakthrough, but it lets scientists “moonlight” by adding new goals to their existing grants, which saves the foundation a lot of winnowing. “And,” he added, “a scientist in a developing country can do a lot with $100,000.”

Over all, he said: “On drawing attention to ways that lives might be saved through scientific advances, I’d give us an A.

“But I thought some would be saving lives by now, and it’ll be more like in 10 years from now.”

RTFA. A case study – series of studies – in developing philanthropy. Above all else, give the Gates’ credit for their commitment and dedication. It ain’t even easy to try to give money away to help people.