Indonesia and Germany signed an agreement this week to install a tsunami early warning system in the Indian Ocean. Though some of the pieces will be in place by October, it could turn out to be a race against time.

The quake that caused last year’s devastating tsunami has increased the stress on other faults nearby, according to a study published this week. This has left the region primed for one or two major earthquakes, and possibly another tsunami.

The earthquake on 26 December, 2004, occurred when the dense India tectonic plate slipped under the Burma plate. This deformed the seabed leading to the tsunami that claimed hundreds of thousands of lives.

When an earthquake occurs in such a subduction zone, where one plate slips under another, it is often followed by another, in addition to the aftershocks. For example, on the Nankai subduction zone to the south-east of Japan, five of the last seven major quakes were followed within five years by major earthquakes along an adjoining segment of the fault, and three of those occurred within a year.

“Big earthquakes make other big earthquakes more likely,” says John McCloskey of the University of Ulster, UK, who led a study that measured the changes in stress in the plate boundaries in the Indian Ocean and Sumatra (Nature, vol 434, p 291). This is because a big earthquake often increases stress in other sections of the same fault or those nearby.

“Strike-slip” fault

McCloskey, working with Suleyman Nalbant and Sandy Steacy, found a dramatic increase in stress in the Sumatra fault, which cuts through the island of Sumatra and runs east of the subduction zone that ruptured last year. The Sumatra fault is a “strike-slip” fault in which two plates slide against each other horizontally.

Before the India-Burma subduction fault gave way, it was pushing on the Sumatra fault, “clamping it shut” says geophysicist Rob McCaffrey of Rensselaer Polytechnic Institute in Troy, New York, US. “When it’s clamped it’s hard to make it slide. Now there’s an increased probability of it slipping.”

McCloskey’s team found that in places the stress along the Sumatra fault had increased by 9 bars. In 1999, the magnitude 7.4 Izmit earthquake in Turkey increased stress in a nearby plate boundary by just 2 bars, and triggered an earthquake of magnitude 7.1 three months later. McCloskey warns that a magnitude 7.5 earthquake could occur along the Sumatra fault.

While it would not cause a tsunami because the fault line is not beneath the ocean, a magnitude 7.5 earthquake under Sumatra would be devastating. “This one will be closer to buildings, maybe in Medan,” says geologist Roger Bilham of the University of Colorado at Boulder, US.

Overdue earthquake

The Sumatra fault is not the only threat. A second quake along the Sunda trench, a continuation of the India-Burma subduction zone, could lead to another tsunami. An earthquake in this area was considered overdue even before the quake farther north on the same fault which caused last year’s tsunami.

“This south-east part of the subduction zone has been accumulating stress since 1833 and 1861, and the recent earthquake will have added more,” says Phil Cummins of Geoscience Australia.

An earthquake in the Sunda trench could potentially reach magnitude 8.5, McCloskey warns, and could trigger another tsunami. Because it would start further south than the one last year, it would probably not strike Thailand, but Sri Lanka and the west coast of Africa could be hit again, as would Sumatra. Seismologist Seth Stein of Northwestern University at Evanston, Illinois, agrees: “If the next bit south broke it could create a comparable tsunami.”

Easing the stress

McCloskey’s calculations show the stress along the Sunda trench to be about 5 bars. However, there is some uncertainty because of how the Earth’s lower crust is reacting to the sudden movement of the upper crust on 26 December. It is therefore possible that that the movement of the lower crust could ease the stress in the Sunda trench, making an earthquake less rather than more likely, McCloskey says.

Peter Malin of Duke University in Durham, North Carolina, US, agrees. “We have huge holes in our data and knowledge of fault zones,” he says. And it’s equally difficult to say when an earthquake would occur. “We are very bad at predicting the timing of when the pressure will be released,” says Bilham. “It could be months, it could be years.”

But the threat of another tsunami, however speculative, has prompted McCloskey to call for a tsunami warning system in the Indian Ocean. “It’s the closest we’ve come to a political statement,” he says. “We’re asking for a political response to a scientific paper.” The Indonesian-German venture could be the answer.

Following the gaze of others is an important skill that many animals are capable of – if one animal in a group sees a predator the others will look round to see what it is looking at, thus alerting them. But there has been much debate as to whether monkeys are able to go one step further and consider the perceptions of others based on where they are looking.

Previous work has suggested they cannot make this connection, but this could be because some previous studies have not used the competitive situations that could bring about this behaviour. “In one study the researcher would try to tell the monkey where the food was using his eyes,” says Jonathan Flombaum, who carried out a new study with Laurie Santos, both of Yale University in New Haven, Connecticut, US. “That’s a foreign situation for them. A monkey would never help others to find food – they compete.”

Flombaum’s own experience suggested the experiments could be providing false results. “The monkeys are good at stealing food from me, and the reason they’re good is that they always try it when I’m not paying attention or am turned the other way,” he says. That behaviour suggests that the monkeys reason that if he is turned away, he cannot see them.

Eye contact

So to better mimic competitive behaviour, two identically dressed human “competitors” stood near individual monkeys in the open with a grape on a platform near each of their feet. Using this basic set-up, they carried out six experiments, each with between 16 and 22 rhesus monkeys.

In every experiment one person was looking in the direction of the platform with the grape on, and one was not, either because he had his back turned, his head turned, eyes averted or his view was obstructed by a board.

The monkeys always preferred to steal the grape from the person that was not looking in that direction, suggesting they were able to reason about what their competitors could see.

“Unsupported interpretation”

But Daniel Povinelli of the University of Louisiana at Lafayette, US, thinks the researchers may be inferring too much from their results. “This debate has been going on since 1978,” he says. “Their theoretical interpretation is unsupported – they haven’t shown that the monkeys are reasoning about the inner psychology and not just responding to the eyes of the experimenters. Eye contact is highly aversive to monkeys so they will avoid that individual. Even just looking at the monkey is sufficient.”

Povinelli also points out that the monkeys on the island where the research took place have been trying to steal food from humans for a long time, so they will have learnt that if someone is facing them they will be shooed away. A research base has been on the island for about 70 years.

But Flombaum believes that with 1000 monkeys and just 10 humans on the island, there is little interaction. He is now working on new experiments to gauge monkeys’ understanding of others. “This experiment shows us they know what people see,” he says. “We now want to find out whether they know what people know.”

Studying monkeys’ neural networks may help understand what goes wrong in the brains of autistic humans, who often do not know what others perceive, he adds.

Journal reference: Current Biology (DOI: 10.1016/j.cub.2004.12.076)

Several fossils from one individual have been discovered at the site, including parts of the ribs, vertebrae, pelvis, shoulder blade and thighbone. But it is the ankle joint that is most interesting, showing that it walked on two legs.

“This skeleton helps us to understand what happened in the joints, how walking upright occurred – what we never had before,” says Bruce Latimer of the Natural History Museum in Cleveland, Ohio, who made the discovery together with Yohannes Haile Selassie of the National Museum in Addis Ababa.

Modern ankles

The discovery was made about 60 kilometres (37 miles) from where the fossilised remains of a hominid called Lucy were found in 1974. At about three million years old and with modern ankles, Lucy was the oldest example of a hominid able to walk upright discovered for many years. These newly discovered fossils are much older, and so may reveal more of the evolution process.

A study of a six million-year-old hominid thighbone in 2004 revealed walking habits closer to humans than chimpanzees, but scientists hope the ankle bone of the new find could reveal exactly how the as yet unclassified creature walked. “Normally, you find one bone or two from an individual and you are happy. Now we have found parts of a skeleton, this is very rare,” adds Latimer.

Despite being older than Lucy, the skeleton is also bigger, with longer legs, which has surprised the scientists and remains unexplained. But they hope and expect that further work will reveal more of how humans evolved. “This is the world’s oldest biped,” says Latimer. “It will revolutionise the way we see human evolution.”

The seven newborn deaths which occur every minute around the world are rarely addressed by governments and agencies because they often occur at home, in countries without adequate registration systems. “It’s the equivalent to all newborn babies in western Europe being wiped out”, says Richard Horton, editor of The Lancet, which published four studies outlining the problem and ways to tackle it.

In developed countries, neonatal deaths – those that occur within the first month of life – account for four in 1000 births, and often occur at the level of expensive intensive care. In the developing world however, 33 in 1000 neonatal babies die, which is more than double the rate seen in developed countries even before high-technology care became available. In parts of Africa, this figure rises to over 50 in 1000 newborn babies dying.

Around 36% of newborn deaths in the developing world are from infections, 27% from premature birth and 23% from asphyxia. But these figures are estimates as less than 3% of neonatal deaths occur in countries with reliable cause-of-death data.

Many children in these areas are not even named, reflecting acceptance amongst communities that are accustomed to high infant mortality rates. “There’s a sense of fatalism where there isn’t adequate care seeking,” says Zulfiqar Bhutta of Aga Khan University in Pakistan, one of the study authors.

Intervention access

The scientists looked at the cost of integrating various intervention methods into current health programmes. They found that a combination of 16 low-technology interventions could save almost three-quarters of the four million babies that die every year if everyone could access them.

Even with 90% coverage, two thirds of the deaths could be prevented. Many of the 500,000 women that die during or soon after childbirth every year could also be saved.

The interventions range from educating women to keep premature babies against their chests and to feed them only with breast milk to providing emergency care during obstructed or breech labours. The provision of early care for babies that develop infections was also stressed, along with teaching birth attendants how to resuscitate babies that stop breathing.

“We need to ensure a continuum of care from the pregnant mother to the newborn to the child,” says Liz Mason from the World Health Organization.

Protective jabs

In some areas of the world many more women could receive basic education and treatment without large investment. In Ethiopia, for example, almost 40% of women live less than five kilometres from a staffed health clinic yet only 5% of women have a skilled attendant present when they give birth.

And in many parts of sub-Saharan Africa, almost 60% of women attend at least two antenatal clinic visits, but only 42% have the two 20-cent injections to immunise against tetanus, which still accounts for 7% of neonatal deaths. Small changes to address these issues could save almost one million babies every year, they suggest. “We don’t have to hold our breath and wait until a pot full of money arrives,” says Carol Bellamy, executive director of UNICEF.

But in the longer term investment is needed, and that has to begin with governments. “The plight of newborn babies is not just a medical issue – it’s also a moral barometer of our times,” says Horton. “The world is yet to accept that the value of a newborn is equal to that of an adult.”

Journal reference: The Lancet – Neonatal Survival edition (March 2005)

The largest ever release of captive chimpanzees into the wild has been declared a success. Five of the 37 chimps released in the Republic of the Congo have bred in the wild, and only five have been confirmed dead. But the scheme was not trouble-free, and has raised questions over whether reintroduction is the most cost-effective way of conserving chimps.

The chimps were all wild-born animals that had been rescued from markets or from owners who no longer wanted them as pets. They were initially transported to islands away from poachers and predators by the charity Ecological Habitat and Freedom of Primates, Congo. Then between 1996 and 2001 they were released into the Conkouati-Douli National Park on the border with Gabon.

The charity’s founder had always intended to return them to the wild. “She thought they deserved to have their life back,” says Joanna Setchell of the University of Cambridge, who co-led the scheme with Benoît Goossens of Cardiff University, UK. There were fears that political instability in the region might have prevented researchers from feeding the island-bound animals, which would then have starved.

But the return to the wild held its own hazards, even in an area with only a few wild chimps. While adolescent females integrated most easily into wild groups, males of all ages and other females were frequently attacked by wild and previously released chimpanzees.

Damaged genitalia

The team documented 47 vicious attacks that left wounds all over the victims’ bodies. Eight attacks on females inflicted wounds on their genitalia, while one male lost a testicle and another two lost parts of their penises in fights. Worse, three males and one female were killed, and without veterinary care around half of the males would have died, the researchers say.

This fits with the chimps’ natural family structure. While males stay within their native group and cooperate in defending a territory, females move to neighbouring groups when they reach around 11 years old. So chimpanzees are used to accepting new females, but attack unfamiliar males. The researchers conclude that male chimps should not be released in areas that already have a chimp population.

The animals were fitted with radio collars, which allowed the 23 animals that stayed in the release area to be tracked. Most of the nine that left the area probably travelled off with groups of wild chimps (see table). The biggest success was that four females bred, producing five offspring in total. A released male called Mekoutou also bred successfully in the wild with a released female called Choupette (��è����Ƶ print edition, 25 January 2003).

Cost per chimp

But looking after the chimps was expensive: the cost of field assistants, the radio collars and veterinary care amounted to $5200 per chimp per year. While applauding the success, some conservationists say the money could have been better spent.

Although wild chimp populations are falling, numbers are not yet so low that reintroduction is necessary, says Nick Salafsky of conservation group Foundations of Success, based in Bethesda, Maryland, US. The more pressing needs are protecting habitat and stopping the bush-meat trade. Without these, he says, the chimps will not have a future anyway. “Are we just rearranging deck chairs on the Titanic?” he asks.

John Fa of the Durrell Wildlife Conservation Trust in Jersey, Channel Islands, UK, agrees that limited resources may be better spent elsewhere. Since rural communities depend heavily on bush-meat for protein in their diet, conservationists need to work with them to provide alternatives, he says.

Setchell accepts that habitat loss and hunting are the priorities, but she still sees a place for reintroduction. She points out that much of the funding for the project came from zoos, and so would probably not have been available to conservation projects. And publicity from the project has increased awareness of the chimps’ plight among locals, she says. “One man came to see them and said: ‘I’ll never eat that again. It looks too much like me’.”

Journal reference: Biological Conservation (DOI: 10.1016/ j.biocon.2005.01.008)

The herb is commercially available but the amount of the active compounds can vary greatly. So to compare St John’s wort to the widely-prescribed antidepressant paroxetine, Meinhard Kieser and his colleagues from Dr Willmar Schwabe Pharmaceuticals in Karlsruhe, Germany, used an extract of the herb.

The researchers assessed improvement during treatment using a standard scale called the Hamilton depression scale. “Healthy people have a score lower than 10 on the scale, while those with depression have a score of at least 14 and the severely depressed around 24 or 25,” explains Angelika Dienel, one of the team.

At the end of a six week trial, hypericum decreased Hamilton depression scores by an average of 14, compared with a decrease of 11 among patients taking paroxetine, suggesting that the St John’s wort extract is at least as effective against severe depression.

No placebo

To select people for the study, 301 volunteers with a Hamilton depression score of at least 22 took a placebo for up to seven days, and those that showed improvement were excluded. It would be have been unethical to give severely depressed people a placebo for the entire study – which lasted six weeks – so no placebo control group was used.

The remaining 251 patients were randomised to take either hypericum or paroxetine. After two weeks the dose was doubled in people whose Hamilton scores did not decrease by at least 20%.

As well as similar improvements in their depression, the hypericum group also reported fewer side effects than those on paroxetine. Just 55% of the group complained of diarrhoea, nausea, dizziness, sweating or upper abdominal pain among others, compared with 76% of the paroxetine group. But people who took the extract were more likely to have upper abdominal pain: 10% compared with 7% of paroxetine users.

However GlaxoSmithKline, which makes paroxetine, points out that a single study cannot adequately assess safety, while paroxetine has 13 years of data behind it, and has been through clinical studies involving 24,000 people.

Drug interference

Previous studies in severely depressed people have failed to show that St John’s wort has any effect over that of placebo, so larger studies may be needed to confirm its potential.

People should talk to their doctor before taking St John’s wort in any form, because it can interfere with other drugs, says Amelia Mustapha of the UK’s Depression Alliance. She says that despite earlier evidence of its use against mild depression, there is still no licensed form of the herb.

“Doctors could prescribe it as they prescribe books or exercise but they don’t feel comfortable doing it because it isn’t standardised,” she says. “You can get St John’s wort teabags with little or no extract in them and how are people to know the difference?”

Journal reference: