Daily Archives: October 18, 2013

News Ireland daily BLOG by Donie

Friday 18th October 2013

Merkel and Schaeuble are friends of Ireland says Michael Noonan


German Finance Minister Wolfgang Schaeuble, left pic. gestures as he speaks to German Chancellor Angela Merkel.

Not clear yet if Ireland will need a lifeline to exit bailout

GERMAN finance minister Wolfgang Schaeuble is a friend of Ireland who would do nothing damaging to the country, Finance Minister Michael Noonan said tonight.

The comments come just days after Mr Schaeuble signalled Europe’s bailout pot was unlikely to pay some of the cost of our multi billion euro bank bailout, despite hopes from the Government to the contrary.

“They don’t have a lot of leverage on us now that we’re nearly out of the (bailout) programme. He wouldn’t do anything that would be damaging to Ireland, ” Mr Noonan told the Dublin Economics Workshop being held in Limerick.

“He’s a friend as is Chancellor Merkel.”

The German comments earlier this week appeared to be the latest blow to Ireland after the country’s second biggest party insisted the Government must raise the 12.5pc corporation tax rate.

Reports last week said early coalition talks between the social democratic SPD and Angela Merkel’s conservative CDU were snagged on Irish issues. The SPD is also completely opposed to the direct recapitalisation of troubled European banks through the European Stability Mechanism (ESM)

Mr Noonan reiterated in the Budget that our 12.5pc rate will be maintained. He said tonight that Tanaiste Eamon Gilmore has a good relationship with the SPD and that there was a “bit of diplomatic activity going on in the background” to ensure that nothing is said in the negotiations to form a coalition that would damage Ireland’s interests.

On elements of the Budget, Mr Noonan said “taking things away from people is always very difficult.”

“It’s probably the hardest thing in politics,” he said.

He said some people had been calling on the Government not to scale back from the originally planned €3.1bn adjustment, but that there had to bepolitical management, pointing out there were little protests following Tuesday’s Budget announcement.

The minister also said that the announcement in the Budget of measures to tackle aggressive tax avoidance by multinationals had not sparked threats from companies to leave the country.

“Actually there’s been a very good international response and by lookingafter our reputation, I think we have enhanced Ireland as a location for foreign direct investment.”

Mr Noonan said the banking sector in Ireland wasn’t sufficient to carry an economy to which he would aspire.

“Im not sure that any banking sector in Europe is at this stage, because they’ve all deliveraged so much,” he said.

Mr Noonan is travelling to Strasbourg and Frankfurt next week to meet with the European Commission and European Central Bank, and the following week to the IMF in Washington, to discuss exiting the bailout.

He said no decision had been made on seeking a so called precautionary credit line, a form of overdraft, to ease the country’s full return to the money markets.

“There is a strong view that we don’t need alternative arrangements. Im risk averse on all these things so Ill take the best advice I can get, we’ll reflect on it and see what our next move will be.”

Funding of €15 million promised for mental health says Minister Lynch 


Mental Health Minister Kathleen Lynch has said she has been assured that €15 million that was due in 2014 for mental health would be restored in 2015 and that she was not disappointed with the €20 million provided in last week’s budget.

She also said she hoped that mental health would secure the full €35 million in 2015 in line with the Programme for Government. Therefore, she hoped that €50 million would be given to mental health in 2015, €35 million as per the Programme for Government and €15 million due from 2014.

Speaking to IMN, Minister Lynch said it was now time to take a step back and review the value that has been provided and service delivered for mental health.

She also said one of her priorities was to ensure that all the promised community mental health posts are in place where they are needed, with a particular emphasis on child and adolescent, old age and intellectual disability mental health teams.

The Programme for Government commits to ringfencing “€35 million annually from within the health budget to develop community mental health teams and services as outlined in A Vision for Change”.

According to the Minister, it is now a good time to consolidate what has been achieved to ensure that resources received to date are utilised to the best possible extent for mental health.

In a statement to IMN, the Department of Health said “mental health has again succeeded in obtaining a substantial ringfenced allocation, within the overall budgetary context. The current economic environment presents a significant challenge for the health system generally in delivering services.  However, mental health is being treated as a priority in so far as we can”.

“This €20 million means that, despite serious resource pressures overall, funding of €90 million has been made available since 2012, up to the end of 2014, that has been specifically earmarked for mental health and suicide prevention,” the Department stated.

The actual amount of funding to be provided to run the mental health service will not be available until the HSE publishes its Service Plan for 2014 in the coming weeks.

The national coalition Mental Health Reform has given a guarded welcome to last week’s Budget announcement.

According to Dr Shari McDaid, Director of Mental Health Reform: “While we welcome the commitment to invest €20 million in 2014 in community mental health services, we had hoped to see the Government fully honour their Programme for Government commitment of €35 million for community mental health services. We are concerned that the €20 million investment will not translate into the needed staff on the ground.”

Sleep cleans the human brain of toxins


The brain uses sleep to wash away the waste toxins built up during a hard day’s thinking, researchers have shown.

The US team believe the “waste removal system” is one of the fundamental reasons for sleep.

Their study, in the journal Science, showed brain cells shrink during sleep to open up the gaps between neurons and allow fluid to wash the brain clean.

They also suggest that failing to clear away some toxic proteins may play a role in brain disorders.

One big question for sleep researchers is why do animals sleep at all when it leaves them vulnerable to predators?

It has been shown to have a big role in the fixing of memories in the brain and learning, but a team at the University of Rochester Medical Centre believe that “housework” may be one of the primary reasons for sleep.

“The brain only has limited energy at its disposal and it appears that it must choose between two different functional states – awake and aware or asleep and cleaning up,” said researcher Dr Maiken Nedergaard.

“You can think of it like having a house party. You can either entertain the guests or clean up the house, but you can’t really do both at the same time.”


Their findings build on last year’s discovery of the brain’s own network of plumbing pipes – known as the glymphatic system – which carry waste material out of the brain.

Scientists, who imaged the brains of mice, showed that the glymphatic system became 10-times more active when the mice were asleep.

Cells in the brain, probably the glial cells which keep nerve cells alive, shrink during sleep. This increases the size of the interstitial space, the gaps between brain tissue, allowing more fluid to be pumped in and wash the toxins away.

Dr Nedergaard said this was a “vital” function for staying alive, but did not appear to be possible while the mind was awake.

She told the BBC: “This is purely speculation, but it looks like the brain is losing a lot of energy when pumping water across the brain and that is probably incompatible with processing information.”

She added that the true significance of the findings would be known only after human studies, but doing similar experiments in an MRI machine would be relatively easy.

Commenting on the research Dr Neil Stanley, an independent sleep expert, said: “This is a very interesting study that shows sleep is essential downtime to do some housekeeping to flush out neurotoxins.

“There is good data on memory and learning, the psychological reason for sleep. But this is the actual physical and chemical reason for sleep, something is happening which is important.”

Dr Raphaelle Winsky-Sommerer, a lecturer in sleep at Surrey University, said: “It’s not surprising, our whole physiology is changing during sleep.

“The novelty is the role of the interstitial space, but I think it’s an added piece of the puzzle not the whole mechanism.

“The significance is that, yet again, it shows sleep may contribute to the restoration of brain cell function and may have protective effects.”

Many conditions which lead to the loss of brain cells such as Alzheimer’s or Parkinson’s disease are characterised by the build-up of damaged proteins in the brain.

The researchers suggest that problems with the brain’s cleaning mechanism may contribute to such diseases, but caution more research is needed.

The charity Alzheimer’s Research UK said more research would be needed to see whether damage to the brain’s waste clearance system could lead to diseases like dementia, but the findings offered a “potential new avenue for investigation”.

Screening significantly reduces death from prostate cancer


(Right picture) Prostate Cancer Picture

The long-running European Randomised Study of Screening for Prostate Cancer (ERSPC) last week published its 11-year follow-up results, which add weight to their original findings by confirming that screening does significantly reduce deaths from prostate cancer.

Published in the New England Journal of Medicine, the study finds that a man who undergoes prostate-specific antigen (PSA) testing will have his risk of dying from prostate cancer reduced by 29 per cent.

Screening for prostate cancer is controversial. Prostate cancer can develop so slowly that it will never cause problems during a man’s lifetime. A major consideration for any national screening protocol, regardless of disease type, is to weigh up the possibility someone will have needless treatment against saving lives.

“The difficulties around screening for prostate cancer occur because the PSA test is not a specific test for prostate cancer; it can only indicate that a man may have a problem with his prostate gland that needs further investigation. Up to two-thirds of men with a raised PSA do not have prostate cancer, therefore routine PSA testing of all men could lead to much anxiety and alarm,” concluded a 2010 analysis on the subject. The US Preventive Services Task Force continued: “The evidence is insufficient to recommend for or against routine screening for prostate cancer using PSA testing or digital rectal examination (DRE).”

Many doctors also argue against PSA testing for men who are in their 70s or older, because even if prostate cancer were detected, most men could be dead of something else before the cancer progressed. Others argue against PSA testing for men who are too young, because too many men would have to be screened to find one cancer, and too many men would therefore have treatment for cancer that would not progress.

The European Randomised Study of Screening for Prostate Cancer, initiated in the early 1990s, aimed to evaluate the effect of screening with PSA testing on death rates from prostate cancer. The trial involved 182,000 men between the ages of 50 and 74 years in seven European countries randomly assigned to a group that was offered PSA screening at an average of once every four years or to a control group that did not receive such screening.

During a median follow-up of almost nine years, the cumulative detected incidence of prostate cancer was 820 per 10,000 in the screening group and 480 per 10,000 in the control group. Deaths from these cancers in this time was much lower.

There were 214 prostate cancer deaths in the screening group and 326 in the control group, a difference of 7.1 men per 10,000 in the tested group compared to the control. The researchers concluded two years ago that PSA-based screening did reduce the rate of death from prostate cancer by 20 per cent, but that this was associated with a high risk of over-diagnosis: 1,410 men would need to be screened and 48 additional cases of prostate cancer would need to be treated to prevent just one death from prostate cancer.

Now, the 11-year follow-up results have confirmed that a man who undergoes PSA testing will have his risk of dying from prostate cancer reduced by 29 per cent. By extending the patient follow-up to an average of 11 years, the study shows that 31 per cent fewer men than previously indicated would need to be diagnosed with cancer to save one life.

As Professor Fritz Schroeder, the international coordinator of the ERSPC study and Professor of Urology, Erasmus Medical Centre, The Netherlands, explains: “Extending the follow-up period strengthens the argument for screening. But it does not decide it. Even so, the risk reduction trend in our study is promising and it is imperative that we continue the follow-up. So far, only about 30 per cent of all men in the study have died. If a larger reduction of prostate cancer mortality is seen by further extending the study beyond the current median of 11 years, we can determine with greater certainty whether the benefit of screening outweighs the disadvantages.

“Screening programmes for prostate cancer will not be feasible until the medical communities can confidently balance the risk of reducing death from prostate cancer with these unacceptably high levels over diagnosis and overtreatment,” adds Prof Schroeder.

Compared with the US, individual PSA testing started late in most European countries and meant that only a relatively small number of men taking part in the control arm of the ERSPC study had previously taken a PSA test.

“This makes the ERSPC study fundamentally different from the US-based Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer screening trial where there was a high contamination rate in the control arm, with at least 44 per cent of participants already PSA-tested prior to being randomised into the study,” says Prof Schroeder.

The PLCO study has been unable to demonstrate any difference in prostate cancer mortality between the two arms of the study.

The ERSPC study and the PLCO study are the scientific world’s main chances to determine the benefits of screening for prostate cancer.

If a relevant difference of 20 per cent or more is shown in these trials at an acceptable cost in terms of quality of life and money, it can be expected that governments worldwide will introduce screening programmes for prostate cancer, which will then be included into paid healthcare policy packages.

“The great hope of all investigators is that this in fact will happen and that early diagnosis can be offered to all men at risk to decrease the burden of suffering and potential death from prostate cancer,” says Pror Schroeder.

Asteroid could collide with Earth in 2032, says Ukrainian astronomers


Scientists say there is a chance an asteroid could hit our planet in 2032, creating an explosion 50 times greater than the most powerful nuclear bomb.

Astronomers say the 1,345-foot (410m) rock could pass by or hit the Earth on 26 August 2032.

The asteroid was discovered moving through the Camelopardalis – or Giraffe – constellation by scientists at the Crimean Astrophysical Observatory in southern Ukraine last week.

“I was watching the Giraffe constellation, monitoring it as part of our comet search programme,” astronomer Gennady Borisov said.

“The first observations show that it moves quickly and is relatively close.”

Astronomers in Italy, Spain, the UK and Russia have now confirmed the presence of the rock, and it has been added to the Minor Planet Center’s list of potentially hazardous asteroids.

If it hit the Earth, the asteroid would create an explosion equivalent to 2,500 megatons of TNT, or 50 times greater than the most powerful nuclear bomb ever used.

However, in reality the threat is minor, with astronomers putting the chance of direct impact at one in 63,000 – the likelihood being that its orbit will miss our planet by some 1.7 million kilometres.

But this did not stop Russian Deputy Prime Minister Dmitry Rogozin announcing that the asteroid would pose a “great challenge for our national space industry” on Twitter.

Mr Rogozin has previously pushed for the development of anti-asteroid defence systems, like former MP Lembit Opik in the UK.

Nasa played down the possibility of impact, with Don Yeoman, manager of the administration’s Near-Earth Object Profram Office, saying: “The current probability of no impact in 2032 [is] about 99.998 per cent.

“This is a relatively new discovery. With more observations, I fully expect we will be able to significantly reduce, or rule out entirely, any impact probability for the foreseeable future.”


News Ireland daily news BLOG by Donie

Thursday 17th October 2013

Budget farce as James Reilly doubts medical card €113m HSE savings


Plans for massive cuts to the medical card scheme have descended into farce after the health minister cast doubt over the target figure outlined in the budget and the HSE said it will have to be independently verified.

The target of €113m through medical card “probity” was foisted on Health Minister James Reilly on Sunday, without any verification or assessment of how it could be achieved.

The embattled minister told the Oireachtas health committee yesterday the figure was “allocated” by Public Expenditure Minister Brendan Howlin.

  “I am speaking frankly and I am concerned about what can be achieved here,” said Dr Reilly. 

He said the figure was based on Mr Howlin’s “deliberations” of a consultancy report by Price Waterhouse Cooper that said €60m to €200m could be achieved through identifying waste from ineligible cards.

“That report is from 18 months ago and obviously a lot of action has been taken since then,” said Dr Reilly.

He has asked the departments of the Taoiseach and public expenditure to carry out a validation of the figure and the impact it would have on the health service.

Tony O’Brien, head of the HSE, said the executive is carrying out an “independent verification process” before the figures are included in its service plan for 2014.

He said if the savings could not be made through probity — or flushing out dud cases — then cuts will hit other health services.

Fianna Fáil has estimated that about 100,000 medical cards would have to be withdrawn in order to reach the €113m figure.

Mr. O’Brien insisted there would be no change to people’s entitlement or the way medical cards are assessed, as a result of the target.

“Therefore, if that €113m cannot reasonably be achieved through probity measures, then an alternative way of meeting that shortfall will have to be found.”

Sources close to Dr James Reilly said €113m was imposed “from the top down” rather than than from the “bottom up” approach of identifying the waste, and then determining what could be saved from its elimination.

They said that James Reilly was given the figure and told to find the savings within it.

The Irish Examiner can also reveal that the HSE raised concerns 18 months ago about the accuracy of the potential savings in the PWC report. A disclaimer by the report’s authors said the savings were “indicative only and cannot be relied on for any purpose other than providing a broad understanding” of the issue.

A further €25m in health savings will be reached by removing medical cards from 35,000 over-70s. The Irish Senior Citizens Parliament who are organising a protest march next Tuesday against the budget “attacks” on Irish elderly people.

Mr O’Brien also raised concerns about changes to tax reliefs for private health insurance in the budget.

The HSE depends on income provided by private patients in public hospital beds, he said. “If there were to be a significant impact on the number of insured patients, that would have a knock-on impact on the funding of the health servicesnext year,” he said.

HSE West group meets over HIQA report on death of Savita Halappanavar


A special board meeting of the HSE West/North West Hospital Group has ended after four hours of talks at Galway University Hospital.

The 12-member board considered the findings and recommendations from three reports following the death of Savita Halappanavar last October.

The findings from the inquest into her death and the recommendations that emerged from the Coroner’s Court were discussed, along with the HSE Clinical Review into the treatment she received and last week’s HIQA report into issues relating to her care at GUH.

The board is not releasing details about decisions made at the meeting until it has communicated with the staff involved tomorrow morning.

It is expected the measures to be taken will then be made public.

Mrs Halappanavar died from an infection caused by sepsis almost a week after she was admitted to hospital on 21 October 2012.

The special board meeting was called following the publication of third report into her care last week.

The master storyteller that was the great cyclist Lance Armstrong


To his millions of fans, American cyclist and cancer survivor Lance Armstrong was more than just a great sportsman, he was an inspiration. To the film-maker who documented his spectacular fall from grace, he was a master storyteller. But were his supporters too ready to believe the fairytale?

The story of the charismatic Texan cyclist who recovered from life-threatening cancer and went on to win the Tour de France a record seven successive times was one of the greatest tales in sporting history.

In 2009, Lance Armstrong attempted to write another chapter into the legend by coming out of professional retirement to compete in the Tour again at the age of 37. He granted Oscar-winning filmmaker Alex Gibney rare access to his inner circle to chronicle the comeback.

For Gibney, the experience was akin to being embedded with the military in a warzone.

“When you’re with a group of soldiers in Iraq or Afghanistan you’re going to end up feeling part of their unit,” he told me.

“I don’t think that’s necessarily wrong. The trick is how to come out of that with some broader perspective – but it’s intoxicating while you’re in the middle of it.”

Gibney admits the “them and us” mentality inside Lance Armstrong’s Astana cycling team encouraged a kind of Stockholm syndrome. Anyone who questioned his repeated denials that he had used performance-enhancing drugs came to be viewed as the enemy.

“I did begin to feel that some people on the outside were a bit fanatical about the subject of whether Lance had doped,” he says. “You can’thelp but take on the vibe of the team.”

Through the media and in the courts, Armstrong aggressively pursued critics who continued to question whether he was riding clean. Alex Gibney watched as his subject attempted to maintain control over the powerful and lucrative myth he had constructed.

“I think the truth in the mind of someone who is a master storyteller does become elastic,” he suggests.

“There’s a moment in the film when Lance loses in Verbier to Alberto Contador (on stage 15 of the 2009 Tour de France) and he says to me ‘I’m sorry I screwed up your documentary.’

“I don’t think that was just banter. I think that was Lance’s way of saying ‘you came to me to deliver the fairytale that everyone’s come to believe that I can deliver and I failed. I’m not going to win. I’m not going to be first and I’m sorry.'”

Armstrong behind eventual 2009 Tour winner Alberto Contador

After Armstrong’s 2009 comeback, in which he finished third, the myth began to disintegrate.

  • Tour de France victories: 1999, 2000, 2001, 2002, 2003, 2004, 2005 (22 individual stage wins)
  • Battle with cancer: Diagnosed with testicular cancer in 1996. The disease spreads through his body. Launches Lance Armstrong Foundation for Cancer. Declared cancer-free in 1997 after brain surgery and chemotherapy
  • Retirement: Announces he will retire after the 2005 Tour de France. Angered by drug allegations against him, he returns to professional cycling in 2009. He finishes third. His accident-filled 2010 Tour is his last

Former teammates went public with allegations of drug use. The US Anti-Doping Agency accused Armstrong of running the most sophisticated and extensive doping scheme in professional sports history.

He finally came clean in an interview with talk show host Oprah Winfrey last January, in which he admitted taking banned substances and undergoing prohibited blood transfusions during all of his victorious Tour de France campaigns.

In earlier films such as Enron: The Smartest Guys in the Room, Taxi to the Dark Side and Mea Maxima Culpa, Alex Gibney has explored the abuse of power by big businesses, the military and the Catholic Church.

In his latest film, it’s Armstrong’s rewriting of his own personal life story, a story that inspired and gave hope to cancer patients around the world, that Gibney finds particularly difficult to accept.

“It’s an abuse of storytelling power,” he says. “He told a story that everyone wanted to believe in too much. He knew how much everybody wanted to believe in it.

“He made the lie so enormous, so all-encompassing, that he couldn’t dial it back. His only choice was to go forward and make it even bigger.” So he carried on cheating, winning Tour after Tour.

Armstrong was engaged to musician Sheryl Crow and travelled by private jet

Stripped of those seven titles, pursued by lawyers seeking to reclaim prize and sponsorship money, Lance Armstrong’s reputation as a sportsman is now in ruins. He has been banned from competitive cycling for life.

Alex Gibney, director of The Armstrong Lie

For Alex Gibney, Lance Armstrong’s epic downfall should serve as a cautionary tale. Even heroes, he argues, need to accept their flaws. “There can be inspirational stories that are messy,” he says.

“Spiderman to me is a more intriguing tale than Superman because you reckon with Peter Parker’s dark past and to some extent his deep-seated anger rather than the pure hero that Superman is.

“When we’re told stories that seem too good to be true we should say to ourselves, ‘Hey, maybe this is too good to be true.'”

Life style changes for humans can save millions from diabetes


MILLIONS of people at risk of developing diabetes could avoid the disease with simple lifestyle changes, say researchers diabetes is preventable with simple lifestyle changes.

A major review of scientific evidence concluded that diet and exercise are vital for staving off the illness, which affects 3.8 million people in Britain.

  Combined with stopping smoking and regular checks on blood pressure and glucose levels, Type 2 diabetes can be prevented altogether, the team from the University of Alberta, Canada, said.

Last month, Diabetes UK said losing weight, eating more fruit and vegetables and taking regular exercise is all people need to do to significantly slash their chance of developing Type 2.

It’s particularly important for people who are already at high risk to talk to their GP to make the diet and lifestyle changes that can help

Dr Matthew Hobbs, Diabetes UK’s head of research

But chief executive Barbara Young said people were not taking the risks seriously and that the country was “sleepwalking towards a public health disaster”.

Dr Matthew Hobbs, the charity’s head of research, said of the findings: “This shows again that it’s particularly important for people who are already at high risk to talk to their GP to make the diet and lifestyle changes that can help.”

Children are drawn to our colourful cigarette packets, A study shows


Children find colourful cigarette packets appealing but are repelled by products that have plain packaging.

The Irish Cancer Society studied pupils from third class in Scoil Aonghusa primary school in Tallaght, Dublin, who were shown branded cigarette packs and asked what they thought of them.

“The children found the packs appealing and were particularly positive about the bright colours and rainbow-coloured effects used on some packs,” it found.

“They felt that the pink slimline packs would appeal to young girls. They also liked the ‘fancy writing’ used on the packs.”

The findings are featured on a new video on YouTube from the Irish Cancer Society.

“Young people are a key target market for the tobacco industry, which needs to recruit 50 new smokers a day to replace those who have either died or quit, in order to keep making profits. Most of these new smokers are children.

“Around 80pc of smokers start before the age of 18 and children in Ireland began smoking at an earlier age than in any other country in Europe,” said a spokeswoman.

The children who were shown examples of what plain packaging may look like responded negatively and called them “disgusting and gross”.

“One of the boys remarked that he did not know how people could buy the cigarettes in plain packs. They felt that plain packs show what it (smoking) does to you and were shocked by the images of the health effects of smoking used on the plain packs.”

Health Minister James Reilly has secured the agreement of the Cabinet to introduce standardised packaging for tobacco products in Ireland, and he welcomed the video.

Drought in East Africa dictated how the brain changed the evolution of human intelligence


Scientists show shifts from dry to wet and back in East Africa’s Rift Valley caused the development of the human brain

Humans evolved their very large brains in response to the dramatic shifts in the climate of East Africa, the cradle of humanity where man’s ancestors are thought to have originated about two million years ago, a study has suggested.

Scientists have matched exceptionally wet periods and very dry periods in the East African Rift Valley to sudden spurts in the evolution of the hominid ancestors of Homo sapiens, which resulted in the evolution of the modern human brain.

Academics have long argued about what led to the unusually large brain of humans with its capacity for language, abstract thought and consciousness. The latest theory suggests it was triggered by the need to adapt to dramatic changes in the local environment of early man.

“It seems modern humans were born from climate change, as they had to deal with rapid switching from famine to feast – and back again – which drove the appearance of new species with bigger brains and also pushed them out of East Africa into Eurasia and South Africa,” said Professor Mark Maslin of University College London, the co-author of the study published in the on-line journal Plos-One.

The Rift Valley is an extensive geological fault marked by mountains, lakes and fertile valleys. Many of the most important fossil remains of early humans have been unearthed in the region, leading to suggestions that it was the most important place for the early origins of man.

The study looked at climate change over the past 5 million years, where there have been large fluctuations between wet periods where lakes were far higher than they are today and dry periods where sand dunes formed in former lake beds.

The scientists found that there were relatively short periods lasting about 200,000 years when East Africa became very sensitive to the cyclical changes in the Earth’s orbit around the Sun – known as Milankovitch cycles – which lead to global-scale changes to the climate, such as ice ages.

In East Africa, these orbital changes to the Earth led to rapid shifts between very dry and very wet periods of about 20,000 years, when typically the lake valleys repeatedly filled up with freshwater and then dried out several times, forcing the human inhabitants to move north or south.

“Due to these changes in orbit, the climate of East Africa seems to go through extreme oscillations from having huge deep freshwater lakes surrounded by rich, lush vegetation to extremely arid conditions, like today, with sand dunes in the floor of the Rift Valley,” Professor Maslin said.

“These changes resulted in the evolution of a new species with bigger brains, and also forced early humans to disperse out of East Africa,” he said.

The study found that there were three time periods in particular when this kind of climate change corresponded to important stages in human evolution.

The first occurred about 2.6 million years ago when the Rift Valley dwellers were pushed into southern Africa and a new species called Homo habilis emerged. The second happened about 1.9 million years ago when an important species called Homo erectus emerged from Africa to colonise much of Asia, while the third occurred about 1 million years ago when Homo heidelbergensis emerged.

Professor Maslin said that the technique is not accurate enough to deal with the past 150,000 years, when Homo sapiens first evolved, but that it nevertheless could explain the earlier evolutionary transition leading to Homo erectus, which is the first large-brained hominid with truly human-like skeleton showing a distinctive adolescent growth-spurt.

Susanne Shultz of Manchester University, the co-author of the study, said that climate change can be linked directly to the evolution of this important human species at a time when there were several species occupying the same geographic region at about the same time.

“We found that around 1.9 million years ago a number of new species appeared, which we believe is directly related to new ecological conditions in the East African Rift Valley, in particular the appearance of deep freshwater lakes,” Professor Shultz said.

“Among these species was early Homo erectus with a brain 80 per cent bigger than its predecessor,” she added.

The present-day lakes of the Rift Valley are much smaller than they would have been at the height of a wet period. Lake Logipi at the northern end of the Kenyan rift valley, for instance, once occupied the entire Suguta Valley, which is presently littered in sand dunes, and was about 300 metres deeper than it is today.