Neanderthal Genome "First Draft" Unveiled

A "first draft" of the Neanderthal genome announced today adds to evidence that the extinct human species was lactose intolerant and could have shared some basic language capabilities with modern humans. The human and Neanderthal family trees split off from each other around 450,000 years ago, after which there was little or no mixing between the two species.

Neanderthals vanished about 30,000 years ago, leaving modern humans to inherit the Earth. Why humans ended up being more successful has long been a topic of debate.

The newly completed sequence shows that humans and Neanderthals have genomes that are 99.5 percent the same.

By comparing the human and Neanderthal genomes with that of our closest living relative, the chimpanzee, researchers hope to tell which genes changed very recently, giving modern humans an edge.

"Studying the Neanderthal genome will tell us what makes modern humans really modern, and really human," said project collaborator Jean-Jacques Hublin, of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Reading the Genome

An animal's genes are made up of base pairs, the "letters" of the genetic alphabet. Genes give organisms their physical traits, from hair color to body shape. By contrast, a genome is the full set of genes that gives rise to a particular species.

Sequencing the more than 3.7 billion base pairs in the Neanderthal genome took about four years. So far the team has read only about 60 percent of the genes.

The initial results, announced today at a press conference at the Max Planck Institute, show intriguing contrasts between us and our ancient cousins.

For example, the research supports previous studies of Neanderthal DNA that show we share the same version of a "language gene" called FOXP2, noted team leader Svante Pääbo, also of the Max Planck Institute.

This gene is involved in linguistic development, suggesting that Neanderthals could talk.

"Although there are many genes involved in language," Pääbo said, "there's no reason to say that they couldn't articulate the way that we do." In addition, the genome offers more proof that Neanderthals couldn't digest lactose as adults, a condition that today affects close to 50 million U.S. adults, according to the American Gastroenterological Association.

"We can see the Neanderthal was not able to drink milk, [after] they were weaned," Pääbo said.

Researchers plan to make more comparisons like this, for instance, by looking at genes involved in brain development.

"In humans, we have a lot of recent evolutionary changes," that could explain our species' differing intellects, said anthropologist John Hawks at the University of Wisconsin in Madison, who was not involved in the project.

"I'll be looking at whether there are parallel changes in the ancient Neanderthal lineage."

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Heroes are born not made, scientists claim

By Richard Alleyne, Science Correspondent in Chicago

; http://link.brightcove.com/services/link/bcpid1488655367/bctid10532714001 http://www.brightcove.com/channel.jsp?channel=1139053637

Professor Deane Aikins, a psychiatrist at Yale University, said a small minority of individuals remain cool even in the most stressful circumstances.

His findings, based on research with the military, found that some individuals did not panic because their body naturally protected them.

Unlike the majority of people who were flooded with a stress hormone, they had much lower levels and also showed signs of another hormone that actually calmed them down.

He referred to Chesley Sullenberger, the pilot of the aeroplane that was successfully landed on the Hudson River in New York last month, as an example.

"There are some individuals who when confronted with extreme stress their hormone profile is rather unique," he said.

"It doesn't reach the same peak as the rest of us. So we're all ready to scream in our chairs, but there are certain individuals who just don't get as stressed.

"Their stress hormones are lower and the peptides that down-regulate that stress are higher, so you can see in action the hormonal regular system really hitting overdrive.

"Certain people are cooler under pressure and they perform very, very well during these periods of time."

Professor Aikins, who outlined his findings at the American Association for the Advancement of Science annual meeting, studied hormone stress levels during extreme training exercises like mock survival or combat swimming.

He said that while there was no such thing as a "man without fear" certain people were better equipped to deal with it.

"I think they were born with it," he said. "We started figuring out we can start predicting who are these individuals who are going to have this cooler hormonal profile under high stress."

He said the research could lead to new training programmes - mental therapies or "push-ups" or medications to make others just as good at dealing with extreme stress.

"So much so we're now getting to the point where we might be able to train people to do better under high stress and there might be ways to augment their hormonal system, mental health push ups might help to better deal with that stress."

He said that it was not that the "heroes" were not scared but they just did not exhibit signs of panic.

"They say wow that was a really miserable day," he said. "But when you say to them did your heart pound or your palm sweat they just say mm well, it was ok."

He said US special forces as a group tend to "run cooler" than non-special forces. He said it was too early to say what percentage of men were born heroes.

Meanwhile other researchers are developing drug therapies for people suffering from Post Traumatic stress Disorder (PTSD) that affects 20 per cent of the soldiers returning from Iraq.

Harvard University are testing a "beta blocker" style drug - often used to reduce blood pressure - to be taken immediately after the trauma that appears to dampen down future PTSD attacks.

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Study: 'Astonishing richness' in polar sea species

By MICHAEL CASEY, AP Environmental Writer

BANGKOK, Thailand – The polar oceans are not biological deserts after all.

A marine census released Monday documented 7,500 species in the Antarctic and 5,500 in the Arctic, including several hundred that researchers believe could be new to science.

"The textbooks have said there is less diversity at the poles than the tropics, but we found astonishing richness of marine life in the Antarctic and Arctic oceans," said Victoria Wadley, a researcher from the Australian Antarctic Division who took part in the Antarctic survey. "We are rewriting the textbooks."

In one of the biggest surprises, researchers said they discovered dozens of species common to both polar seas — separated by nearly 7,000 miles (11,000 kilometers). Now they have to figure out how they separated.

"We probably know more about deep space than we do about the deep polar oceans in our own backyard," said Gilly Llewellyn, leader of the oceans program for the environmental group WWF-Australia. She did not take part in the survey. "This critical research is helping reveal the amazing biodiversity of the polar regions."

Most of the new discoveries were simpler life forms known as invertebrates, or animals without backbones.

Researchers found scores of sea spider species that were as big as a human hand, and tiny, shrimp-like crustaceans in the Arctic basin that live at a depth of 9,850 feet (3,000 meters).

The survey is one of several projects of the Census of Marine Life, an international effort to catalog all life in the oceans. The 10-year census, scheduled for final publication in 2010, is supported by governments, divisions of the United Nations and private conservation organizations.

The survey — which included over 500 polar researchers from 25 countries — took place during International Polar Year which ran in 2007-2008.

Researchers endured up to 48-foot (16-meter) waves on their trip to the Antarctic, while their colleagues in the Arctic worked under the watchful eye of a security guard hired to protect them from polar bears.

New technology also helped make the expeditions more efficient and productive than in the past. Researchers used cell-phone-like tracking devices to record the Arctic migration of narwhals, a whale with a long twisted tooth, and remotely operated submersibles to reach several miles (kilometers) down into the oceans to study delicate marine animals that are impossible to collect.

As many as 235 species were found in both polar seas, including five whale species, six sea birds and nearly 100 species of crustaceans.

"We think of the Arctic and Antarctic as similar habitats but they are separated by great distances," said University of Alaska Fairbanks plankton ecologist Russ Hopcroft, who took part in the Arctic survey.

"So finding species at both ends of the Earth — some of which don't have a known connection in between — raises a whole bunch of evolutionary questions," he said.

Hopcroft and other polar researchers will now try to determine how long these species have been separated and whether they have drifted apart genetically.

David Barnes, of the British Antarctic Survey, said there a number of possibilities to explain how similar species live so far apart.

Some may have traveled along the deep-sea currents that link the poles or may have thrived during the height of the last ice age about 20,000 years ago when the polar environment was expanded and the two habitats were closer.

Hopcroft and Barnes cautioned that more work needs to be done to confirm whether the 235 species are indeed the same or differ genetically.

"Painstaking work by geneticists investigating both nuclear and mitochondrial genes will only be able to confirm this," Barnes said in an e-mail interview. "It may be they separated sometime ago but similar selective pressures have meant they have not changed much."

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