Pause in Arctic's melting trend

By Richard Black Environment correspondent, BBC News website

Walrus have been seen on Alaska's north coast in unusual numbers

This summer's melt of Arctic sea ice has not been as profound as in the last two years, scientists said as the ice began its annual Autumn recovery.

At its smallest extent this summer, on 12 September, the ice covered 5.10 million sq km (1.97 million sq miles).

This was larger than the minima seen in the last two years, and leaves 2007's record low of 4.1 million sq km (1.6 million sq miles) intact.

But scientists note the long-term trend is still downwards.

They note that at this year's minimum, the ice covered 24% less ocean than for the 1979-2000 average.

The analysis is compiled from satellite readings at the US National Snow and Ice Data Center (NSIDC) in Boulder, Colorado.

Colder front

Among the reasons for the less drastic melt are that Arctic temperatures have been cooler this year than last, researchers said, and that winds have helped disperse sea ice across the region.

Arctic ice in retreat

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NSIDC scientist Walt Meier said the reasons for the somewhat cooler temperatures this year were not entirely clear yet.

"We had cloudier conditions and low pressure zones in late summer that probably helped keep temperatures down," he told BBC News.

"It's something we need to look at in more detail.

"But it certainly wasn't as warm as 2007, which was in the order of 2-3C warmer than the average in a lot of places."

The question now, he said, was whether 2007 turns out to be a "high-melt blip", or whether 2009 turns out to be a "low-melt blip" - which will not become evident until next summer at the earliest.

What continues to have scientists worried is that a significant proportion of the cover consists of young, thin ice formed in a single winter.

This is much more prone to melting than the older, thicker ice that dominated in years gone by.

"If we get another warm year, anything like 2007, then the ice is really going to go," said Dr Meier.

"And the chances are that at some point in the next few years we are going to get a warm one."

White heat

In recent decades, the Arctic region has been warming about twice as fast as the average for the Earth's surface.

Recently, scientists specialising in reconstructing past temperatures released data showing that the current decade is the warmest in the Arctic for at least 2,000 years.

Melting ice is a "positive feedback" mechanism driving temperature rise faster. Whereas white ice reflects sunlight back into space, dark water absorbs it, leading to faster warming.

The NSIDC team cautions that this is a preliminary analysis and that further melt is possible, though unlikely, this year.

Next month they will publish a full analysis including more details of how temperatures, currents and winds affected the sea ice this summer.

Kenya: Government destroys the Ogiek's forest

Alert Bulletin from Survival International

Kenya: Serikali yaharibu Msitu wa Wa-Ogiek

'Kutoa makazi kwa watu wengine katikati yetu ina maana kuwa mila ua Wa-Ogiek itakufa na sis tutapotea kabisa.' Joseph Towett, Mwenyekiti wa Halmashauri ya Wa-Ogiek

Jamii ya Wa-Ogiek wa Kenya wanapinga serikali inayokusudia kuharibu msitu ambao ni mahali pao pa kuishi.

Jamii hii yenye karibu watu 14,000 wameishi hapo tangu zama za kale katika mlima wa msitu wa Mau unaoelekea bonde la ufa kwa upande wa Kenya. Jamii hii huishi kwa kutegemea ukusanyaji wa matunda mwitu na uwindaji, ingawa wanafahamika pia kwa umaarufu wao wa kukusanya asali kutoka mizinga iliyotundikwa katika matawi makubwa ya miti ya msitu huo. Pamoja na kuwa wala asali maarufu, Wa-Ogiek pia hufanya biashara na majirani zao waishio nje ya msitu. Baadhi ya Wa-Ogiek waishio ndani ya msitu huishi kwa kutegemea ukusanyaji na uwindaji tu, wengine hukamilisha mahitaji yao ya chakula kwa kulima mboga kidogo na ufugaji. Kwa Wa-Ogiek wote, ufugaji nyuki na okusanyaji wa asali ni sehemu muhimu ya aina ya maisha yao. Kama wakusanyaji/wawindaji hawapewi heshima inayostahili na majirani zao ambao ni wafugaji.

Mau ni makazi ya asili ya Wa-Ogiek, ni sehemu iliyotengwa maalum na serikali ya Kenya chini ya sheria ya Misitu. Tangu nyakati za Wakoloni, serikali imejaribu kuwatoa kutoka msituni chini ya kigezo cha 'kulinda mazingira' kutoka shughuli za Wa-Ogiek; lakini mwaka huu mamlaka inayohusika imejaribu kuwatoa nje ya makazi yao ya asili. Lakini siku zote watu hawa wamejaribu kurudi kwao ingawa sasa wamepata vitisho vikali zaidi.

Kwa madai kuwa msitu unahitaji kulindwa kutoka jamii hizi ambazo kwa namna nyingine wametunza mazingira yake vema, serikali ya Kenya imefungua karibu heckta 60,000 kwa matumizi ya sekta binafsi. Watakaofaidika na hatua hii, wengi si Wa-Ogiek, ila ni wafanyabiashara kama vile wa mashamba ya chai, wakata mbao na wakulima kutoka sehemu zingine za Kenya. Kampuni kubwa tatu za mbao kwa mfano, Pan-African paper Mills, Raiply Timber na Timsales Ltd – tayari zinaendesha shughuli zao katika msitu huu.

Kuruhusu wageni ndani ya msitu wa Mau ni sehemu ya kampeni ya kufungua moja ya kati ya sehemu kumi za misitu ya Kenya kwa makazi ya watu wasio na ardhi – msitu wa Mau ukiwa ni mmoja wao. Tatizo kubwa ni kuwa hatua hii ya serikali ikitekelezwa, Wa-Ogiek wataingia katika idadi ya Wakenya wasio na ardhi na wasio na hadhi na watapotea kama watu. Licha ya hivyo, mpango huu pia unatishia usalama wa mazingira ya Kenya kwa sababu msitu huu ni eneo muhimu kwa ukusanyaji wa vianzo vya maji. Tayari ukame umeikumba Kenya na wataalamu wanakubali kuwa kupotea kwa msitu huu kutaongeza tatizo hili na itaathiri eneo kubwa zaidi hadi eneo la jirani yao Tanzania.

Mpango wa kufungua misitu ya taifa ulitangazwa kwa mara ya kwanza januari mwaka huu 2001, na ulifungua mlango wa upinzani mkali kutoka pande zote za dunia. Upinzani ulitokea pia toka bunge la Kenya na makundi ya wanamazingira. Chama cha Maendeleo ya Wa-Ogiek kilipata amri ya mahakama kuu ya Kenya ikiamuru kusimamisha ufunguaji wa hekari 35,000 za upande wa mashariki ya Msitu wa Mau hadi usuluhishi wa kesi waliyopeleka mahakamani kupinga hatua hiyo mnamo mwaka 1997. Mamlaka ya halmashauri yalitoa vitisho kwa jamii hii ili ifute kesi hii lakini wao walisimama imara na hawakufuta, mzee mmoja aliiambia mamlaka hii kuwa 'hakuna kiasi cha vitisho kitakachowafanya waache kudai haki yao ya asili waliyopewa na Mungu na ya kikatiba.' Katika mazingira ya kawaida ya kukataa kujibu madai ya Wa-Ogiek, kesi hii imeahirishwa. Hata hivyo uchoraji ramani wa eneo hilo umeendelea licha ya amri ya mahakama. Mara eneo la mashariki la mlima huu litakapofunguliwa, maeneo mengine ya mlima huu yatafuata.

Mnamo mwezi wa kumi wa mwaka huu, Waziri wa Mazingira alitoa amri ya kuruhusu kufungua maeneo haya ya mlima huu na kuna taarifa kuwa wakata mbao wameshaanza kusafisha maeneo yaliyotolewa. Kwa kuchukua hatua hii, serikali inapingana na maoni ya kimataifa, utaratibu wake wa kisheria, na haki za Wa-Ogiek chini ya sheria za kimataifa na inahatarisha usalama wa Wa-Ogiek kama watu.

Tafadhali andika kwa kifupi na kwa lugha nzuri barua au fax kwa Kiswahili au Kiingereza au kwa lugha yako mwenyewe na ingiza mambo yafuatayo:

• Haki ya Wa-Ogiek kumiliki ardhi yao ya asili inatambulika katika sheria za kimataifa na ni lazima itambulike.

• Kufunguliwa kwa msitu wa Mau kutakiuka amri ya Mahama Kuu ya Kenya na itaongeza kiwango cha kudharau mahakama.

• Kupima na kuweka mipaka katika maeneo yenye mgogoro ndani ya msitu huu ni lazima kusimamishwe.

Tafadhali andika kwa

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ENGLISH :

Kenya: Government destroys the Ogiek's forest

"Settlement of other people in our midst would mean that the Ogiek culture would cease. We will be wiped out." Joseph Towett, Chairman, Ogiek Welfare Council.

The Ogiek people of Kenya are resisting a government that seems determined to destroy their forest home.

The Ogiek, who number about 20,000, have lived since time immemorial in the Mau mountain forest overlooking Kenya's Rift Valley. They live by gathering wild plants and hunting, but most of all they are famous as collectors of honey from beehives in the high branches of the forest trees. As well as eating this honey themselves, they also trade with neighbouring peoples living outside the forest. Some Ogiek in the deep forest live purely by hunting and gathering; others supplement their hunting with small vegetable plots and some livestock. For all Ogiek, bee-keeping and collecting honey remain central to their way of life. As a hunter-gatherer people they are looked down on by their cattle-herding neighbours.

Mau, the Ogiek's ancestral home, is a protected area under Kenya's Forest Act. Ever since colonial times, governments have tried to evict them from the forest, under the fiction of 'protecting the environment' from the Ogiek's activities; even this year the authorities have tried to throw the Ogiek out of their homeland. Up until now, the Ogiek have always made their way back. But now they are facing the worst threat yet.

While still claiming that the forest needs protection from these hunter gatherers who have always managed it sustainably, the Kenyan government has opened up nearly 60,000 hectares of it for private use. Those who will benefit are mostly not the Ogiek, but developers such as tea planters and loggers, along with settlers from elsewhere in the country. Three powerful logging companies – Pan African Paper Mills, Raiply Timber, and Timsales Ltd – are already active in the forest.

Allowing outsiders into the Mau forest is in fact part of a larger vote-winning scheme to open up around one tenth of Kenya's forests for settlement by some of the country's many landless people – the Mau forest makes up a large proportion of the total area being opened up. The tragedy is that if the government's scheme goes ahead, the Ogiek will simply join the numbers of Kenya's dispossessed and die out as a people. The plan also threatens Kenya's environment, as the Mau forest is a vital water catchment area. Drought is already endemic in Kenya, and experts agree that the loss of forest cover will worsen the problem, affecting neighbouring Tanzania also.

The plan to open up the nation's forests was first announced in January 2001, sparking a wave of international protest. There was opposition in the Kenyan parliament, and protests and petitions from environmentalists. The Ogiek Welfare Association obtained an order from the Kenya High Court halting the opening up of 35,000 hectares in East Mau until after the resolution of a case which they had filed in defence of their land as long ago as 1997. Local authorities tried, through threats and intimidation, to make the Ogiek withdraw the case, but they remained firm; one elder told the local head of government, 'No amount of intimidation will deter us from demanding our God-given right within the constitution.' In an obvious attempt to avoid answering the Ogiek's claims, the case has been postponed. Yet surveying of the disputed land has gone on, in clear contempt of court. Once the East Mau has been opened up, the same is likely to happen to other Ogiek areas.

In October 2001, the environment minister gave the order to go ahead with the opening up of these forest areas, and there are reports that loggers have already started systematic clearing of the newly-opened forest tracts. By going ahead, the Kenyan government is defying international opinion, its own legal system and the Ogiek's rights under international law, and is endangering the survival of the Ogiek as a people.

Please write a brief and polite letter or fax (in Kiswahili, English or your own language) including these points:

• The right of the Ogiek people to the ownership of their ancestral land is enshrined in international law and must be recognised.
• The opening up of East Mau Forest would be a blatant violation of High Court orders, and by extension a contempt of court.
• Surveying and logging in all the disputed areas of the Mau forest must be stopped.

Please send your letter to

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world's primates says 48% of species face extinction,

Primates 'face extinction crisis'

By Mark Kinver Science and nature reporter, BBC News

Under pressure: The Critically Endangered grey-shanked douc langur is one of the primates in peril

A global review of the world's primates says 48% of species face extinction, an outlook described as "depressing" by conservationists.

The IUCN Red List of Threatened Species says the main threat is habitat loss, primarily through the burning and clearing of tropical forests.

More than 70% of primates in Asia are now listed as Endangered, it adds.

The findings form part of the most detailed survey of the Earth's mammals, which will be published in October.

PRIMATES IN PERIL Nations with the highest percentage of threatened species: Cambodia - 90% Vietnam - 86% Indonesia - 84% Laos - 83% China - 79% (Source: IUCN Red List)

Other threats include hunting of primates for food and the illegal wildlife trade, explained Russell Mittermeier, chairman of global conservation group IUCN's Primate Specialist Group and president of Conservation International.

"In many places, primates are quite literally being eaten to extinction," he warned.

"Tropical forest destruction has always been the main cause, but now it appears that hunting is just as serious a threat in some areas, even where the habitat is still quite intact."

The survey, involving hundreds of experts, showed that out of 634 recognised species and subspecies, 11% were Critically Endangered, 22% were Endangered, while a further 15% were listed as Vulnerable.

Asia had the greatest proportion of threatened primates, with 71% considered at risk of extinction. The five nations with the highest percentage of endangered species were all within Asia.

'Depressing' picture

"It is quite spectacular; we are just wiping out primates," said Jean-Christophe Vie, deputy head of the IUCN Species Programme.

RED LIST DEFINITIONS The Tonkin snub-nosed monkey is listed as Critically Endangered Extinct - Surveys suggest last known individual has died Critically Endangered - Extreme high risk of extinction - this means some Critically Endangered species are also tagged Possibly Extinct Endangered - Species at very high risk of extinction Vulnerable - Species at high risk of extinction Near Threatened - May soon move into above categories Least Concern - Species is widespread and abundant Data Deficient - not enough data to assess

He added that the data was probably the worst assessment for any group of species on record.

"The problem with these species is that they have long lives, so it takes time to reverse the decline. It is quite depressing."

Although habitat loss and deforestation were deemed to be the main threats globally, Dr Vie explained how human encroachment into forests was also creating favourable conditions for hunters.

"This creates access, allowing people to go to places that they could not go in the past," he told BBC News.

"Primates are relatively easy to hunt because they are diurnal, live in groups and are noisy - they are really easy targets.

"Many of the Asian primates, like langurs, are 5-10kg, so they are a good target. Generally, you find that what is big and easy to get disappears very quickly."

In Africa, 11 of the 13 kinds of red colobus monkeys assessed were listed as Critically Endangered or Endangered.

Conservationists fear that two may already be extinct. The Bouvier's red colobus has not been seen for 25 years, and no living Miss Waldron red colobus has been recorded since 1978.

The authors of the primate Red List did consider downlisting mountain gorillas to Endangered from Critically Endangered because the great apes had recorded a population increase.

But they decided to delay reclassification as a result of five of the gorillas being killed in July 2007 by gunmen in the DR Congo's Virunga National Park, which is still at the centre of a conflict between rebel forces and government troops.

During 2007, wildlife rangers in the park recorded a total of 10 gorilla killings. The rangers have been documenting their struggles in a regular diary on the BBC News website over the past year.

Mountain gorillas have been caught in the crossfire of a land dispute Diary: Protecting mountain gorillas

"If you kill seven, 10 or 20 mountain gorillas, it has a devastating impact on the entire population," Dr Vie explained.

"Within the Red List criteria, you are allowed to anticipate what will happen in the future as well as look at what has happened in the past.

"So it was decided not to change the mountain gorillas' listing because of the sudden deaths, and we do not know when it is going to stop."

Dr Emmanuel de Merode, chief executive of Gorilla.cd - an EU-funded programme working in Virunga National Park - said the gorillas' long-term survival was still far from assured.

"Militias have been in control of the Gorilla Sector since September last year, which means the Congolese wildlife authority has been unable to manage the area and protect the gorillas," he told BBC News.

"Until the war ends and the rangers are able to get back in and patrol the area, we have no idea as to the fate of almost a third of the mountain gorillas left in the world."

Golden glimmer of hope

Despite the gloomy outlook, the Red List did record a number of conservation successes.

The re-introduction of golden lion tamarins is one of the few successes

Brazil's populations of golden lion tamarins and black lion tamarins were downlisted from Critically Endangered to Endangered.

"It is the result of decades of effort," said Dr Vie. "The lion tamarins were almost extinct in the wild, but they were very popular in zoos so there was a large captive population.

"So zoos around the world decided to join forces to introduce a captive breeding programme to reintroduce the tamarins in Brazil."

However the first attempts were not successful and the released population quickly crashed because the animals were ill-prepared for life in the wild, he recalled.

"They were not exposed to eagles or snakes and they did not know how to find food, so a lot of them died. But some did survive and, slowly, the numbers began to increase."

Ultimately, the success was a combination of ex-situ conservation in zoos and in-situ conservation by protecting and reforesting small areas around Rio de Janeiro and Sao Paulo.

"It took time, money and effort at all levels, from the politicians to scientists and volunteers on the ground, for just two species."

The findings, issued at the International Primatological Society Congress in Edinburgh, Scotland, will be included in a survey described as an "unprecedented examination of the state of the world's mammals", which will be presented at the IUCN World Conservation Congress in October.

Climate focus 'good news for species' ?population ?

Climate focus 'good news for species'

VIEWPOINT Russell Mittermeier

Climate change could actually benefit some of the world's most endangered species, says Conservation International president Russell Mittermeier. In this week's Green Room, he explains that conservationists should capitalise on the worldwide attention being given to global warming.

The good news is that the unprecedented spotlight on climate change is also shedding light on how tropical forests balance our Earth's climate

Climate change could be the best thing that ever happened to the amazing array of animal and plant species that make up the Earth's biodiversity.

Don't get me wrong; climate change is the most serious environmental threat we have ever encountered, and it is already taking a terrible toll on species, as well as people, all over the world.

The silver lining is that climate change has triggered a universal wake-up call that we all hear, and are beginning to heed.

Never before have so many sectors of society been equally concerned and motivated to combat an environmental threat.

Of course, some die-hard pessimists say it's too late, that the climate change train has left the station and there is nothing we can do but get ready for catastrophic consequences.

Nothing could be more wrong. Just ask the thousands of participants at the World Conservation Congress (WCC) now taking place in Barcelona, Spain.

MAMMALS IN PERIL Hunting and habitat loss has left the Caspian seal struggling to survive Mammals facing extinction threat

Representatives from governments, indigenous peoples, industry and environmental groups are meeting to present innovations and create partnerships.

Climate change and protecting species are focal points, and pessimism is not on the agenda. Instead, smart constructive ideas for solutions are being shared.

We estimate the Earth harbours a minimum of six million living species, from microscopic bacteria to magnificent great apes.

The major news announced at the WCC on Monday was that the latest assessment of the world's mammals shows more than 20% to be threatened with extinction.

That includes 188 mammals, such as the Iberian Lynx, in the highest threat category of Critically Endangered.

This assessment is part of the IUCN Red List of Threatened Species, which now includes 44,838 species, of which 16,928 (38%) are threatened with extinction.

Self preservation society

Why should people care about the fate of these plants and animals?

In the most simple terms, we should care because the quality of our lives ultimately depends on them.

Without species diversity, we wouldn't have the healthy ecosystems that supply our food, cleanse our air and water, provide sources of life-saving medicines and help stabilise our climate.

Demise of the devils and other mammals under threat In pictures

We would also miss out on a free and ubiquitous source of miraculous beauty and endless possibilities.

We continue to discover new species every day. Just since 1994, we've discovered 54 new lemur species on the Indian Ocean island nation of Madagascar.

The thrill of documenting a new primate is tempered, however, with the knowledge that many species will become extinct before they are even discovered.

On a global scale, we're losing species 1,000 times faster than what scientists consider normal.

It is an insidious, silent epidemic that could wreck our planet's ability to heal itself.

While the Red List does make headlines, somehow the irreplaceable loss of species does not stay in the minds of the general public, and it has certainly never prompted major financial investments.

This has always puzzled me. As a colleague of mine puts it: "Imagine what would happen to us if rainfall was a thousand times more than normal? What if snowfall were a thousand times more than normal? What if rates of disease transmission for malaria or HIV/AIDS were a thousand times higher than they are now? That is what is happening to plant and animal biodiversity today."

Just as climate change threatens us with rising sea levels, droughts, floods and more category five hurricanes, it is also one of the greatest threats to species.

We could lose more than 30% of the Earth's plants and animals this century due to shifts in the Earth's climate.

Conservationists describe the outlook for primates as "depressing" Primates 'face extinction crisis'

So where is the silver lining?

The good news is that the unprecedented spotlight on climate change is also shedding light on how tropical forests balance our Earth's climate.

At least and possibly much more than 20% of the greenhouse gases that contribute to climate change come from forest destruction - that's more than from all the world's cars, trucks, airplanes and trains combined.

At the same time, forests are effectively our life support system, absorbing carbon dioxide and emitting oxygen.

Those same tropical forests are also home to the world's greatest preponderance of species diversity.

Remove the forests and you will also exterminate countless species. By the same token, the species are essential to healthy forests for many reasons, including pollination and seed dispersal.

There is still time to protect these forests while also providing economic opportunities to developing countries and local people.

One of the key issues at the WCC in Barcelona is how conserving standing tropical forests to fight climate change must be included in a new United Nations agreement to replace the Kyoto Protocol, the current climate change treaty that expires in 2012.

If we ensure that nations will be compensated for forest conservation that reduces emissions, we will also contribute to redressing some of the huge economic imbalances that exist in the world, since many tropical forest countries are among the more economically stressed.

A message Barcelona can send to the rest of the world is that it is not too late to protect species as well as combat climate change.

On both counts, the welfare of humanity is at stake.

the hoofed group including goats, bison and cattle.

Horse genome unlocked by science

The horse genome could yield clues to human disease

The genome of a domestic horse has been successfully sequenced by an international team of researchers.

The work, published in the journal Science, may shed light on how horses were domesticated.

It also reveals similarities between the horse and other placental mammals, such as bovids - the hoofed group including goats, bison and cattle.

The authors also found horses share much of their DNA with humans, which could have implications for medicine.

Horses suffer from more than 90 hereditary diseases that show similarities to those in humans.

"Horses and humans suffer from similar illnesses, so identifying the genetic culprits in horses promises to deepen our knowledge of disease in both organisms," said co-author Kerstin Lindblad-Toh, from the Broad Institute at the Massachusetts Institute of Technology (MIT) in Cambridge, US.

"The horse genome sequence is a key enabling resource toward this goal."

To generate a high-quality genome sequence, the researchers analysed DNA from an adult female thoroughbred named Twilight.

The horse's DNA was sequenced using capillary DNA sequencing technology (known as Sanger sequencing) to reveal a genome that is roughly 2.7 billion "letters", or nucleotides, in size.

In addition to sequencing the genome of a thoroughbred horse, the researchers also examined DNA from a variety of other horse breeds.

These included the American quarter horse, Andalusian, Arabian, Belgian draft horse, Hanoverian, Hokkaido, Icelandic horse, Norwegian fjord horse, and Standardbred breeds.

The team surveyed the extent of genetic variation both within and across breeds to create a catalogue of more than one million single-letter genetic differences in these breeds.

This is slightly larger than the genome of the domestic dog, and smaller than both the human and cow genomes.

So far, scientists have also sequenced the genomes of the platypus, mouse, rat, chimpanzee, rhesus macaque and, of course, human.

Horses were first domesticated 4,000 to 6,000 years ago. Over time, as machines have become the chief sources of agricultural and industrial muscle, those roles have shifted to sport and recreational activities.

'The myth of the chemical cure'

VIEWPOINT Dr Joanna Moncrieff Mental health expert

Taking a pill to treat depression is widely believed to work by reversing a chemical imbalance.

Medication is a mainstay of mental health therapy

But in this week's Scrubbing Up health column, Dr Joanna Moncrieff, of the department of mental health sciences at University College London, says they actually put people into "drug-induced states".

If you've seen a doctor about emotional problems some time over the past 20 years, you may have been told that you had a chemical imbalance, and that you needed tablets to correct it.

It's not just doctors that think this way, either.

Magazines, newspapers, patients' organisations and internet sites have all publicised the idea that conditions like depression, anxiety, schizophrenia and bipolar disorder can be treated by drugs that help to rectify an underlying brain problem.

People with schizophrenia and other conditions are frequently told that they need to take psychiatric medication for the rest of their lives to stabilise their brain chemicals, just like a diabetic needs to take insulin.

The trouble is there is little justification for this view of psychiatric drugs.

Altered states

First, although ideas like the serotonin theory of depression have been widely publicised, scientific research has not detected any reliable abnormalities of the serotonin system in people who are depressed.

Second, it is often said the fact that drug treatment "works" proves there's an underlying biological deficiency.

Psychoactive drugs make people feel different Read your comments

But there is another explanation for how psychiatric drugs affect people with emotional problems.

It is frequently overlooked that drugs used in psychiatry are psychoactive drugs, like alcohol and cannabis.

Psychoactive drugs make people feel different; they put people into an altered mental and physical state.

They affect everyone, regardless of whether they have a mental disorder or not.

Therefore, an alternative way of understanding how psychiatric drugs affect people is to look at the psychoactive effects they produce.

Drugs referred to as antipsychotics, for example, dampen down thoughts and emotions, which may be helpful in someone with psychosis.

Drugs like Valium produce a state of relaxation and a pleasant drowsiness, which may reduce anxiety and agitation.

Drugs labelled as "anti-depressants" come from many different chemical classes and produce a variety of effects.

Prior to the 1950s, the drugs that were used for mental health problems were thought of as psychoactive drugs, which produced mainly sedative effects.

'Informed choice'

Views about psychiatric drugs changed over the course of the 1950s and 1960s.

FROM THE TODAY PROGRAMME More from Today programme

They gradually came to be seen as being specific treatments for specific diseases, or "magic bullets", and their psychoactive effects were forgotten.

However, this transformation was not based on any compelling evidence.

In my view it remains more plausible that they "work" by producing drug-induced states which suppress or mask emotional problems.

If we gave people a clearer picture drug treatment might not always be so appealing

This doesn't mean psychiatric drugs can't be useful, sometimes.

But, people need to be aware of what they do and the sorts of effects they produce.

At the moment people are being encouraged to believe that taking a pill will make them feel better by reversing some defective brain process.

That sounds good. If your brain is not functioning properly, and a drug can make it work better, then it makes sense to take the pill.

If, on the other hand, we gave people a clearer picture, drug treatment might not always be so appealing.

If you told people that we have no idea what is going on in their brain, but that they could take a drug that would make them feel different and might help to suppress their thoughts and feelings, then many people might choose to avoid taking drugs if they could.

On the other hand, people who are severely disturbed or distressed might welcome these effects, at least for a time.

People need to make up their own minds about whether taking psychoactive drugs is a useful way to manage emotional problems.

To do this responsibly, however, doctors and patients need much more information about the nature of psychiatric drugs and the effects they produce.

Dr Moncrieff's book "The Myth of the Chemical Cure", published by Palgrave Macmillan, will be available in paperback from September