Day: 11/23/2012

Giant Eocene bird was ‘gentle herbivore’, study finds.

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Footprints believed to have been made by the giant bird Diatryma indicate that it was a “gentle herbivore” and not a fierce carnivore, scientists say.

A team of researchers from Washington, US, examined tracks uncovered in a landslide in 2009.

Previous investigations have suggested the giant bird was a carnivorous predator or scavenger.

But the absence of raptor-like claws in the footprints supports the theory that Diatryma was not a meat-eater.

Measuring 7ft (2.13m) tall and with a huge head and beak, the giant flightless bird Diatryma(believed by some experts to belong to the genus Gastornis) is commonly portrayed as a fierce predator in both scientific works and popular media.

The animal is frequently thought as “the bird that replaced dinosaurs as the top predator”, said geologist and team member George Mustoe, from Western Washington University in Bellingham, US.

“Let’s be honest: scary, fierce meat-eaters attract a lot more attention than gentle herbivores.”

The study, published in the journalPaleontology, analysed a set of footprints made 55.8 to 48.6 million years ago in the Lower Eocene. Preserved in sandstone, the prints formed part of the Chuckanut Formation in northwest Washington, US.

The team concluded that the multiple, well-preserved tracks were most likely to have been made by Diatryma.

That would make them the only known footprints left behind by this giant bird, and they provide new evidence about what it ate.

“[The tracks] clearly show that the animals did not have long talons, but rather short toenails,” said David Tucker, from Western Washington University, who also worked on the study.

“This argues against an animal that catches prey and uses claws to hold it down. Carnivorous birds all have sharp, long talons.”

Early palaeontologists studying Diatryma fossils concluded that the giant bird was a predator because of its size, huge head and large beak.

The first Diatryma skeleton found in the US was preserved alongside bones of tiny horses and other small mammals. Some scientists posited that these must have been the bird’s prey, explained Mr Mustoe.

However, Diatryma also had relatively short legs, leading others to suggest it could not have run fast enough to capture prey, and was therefore a herbivore.

Further analysis has shown that the bird did not have a hook on the end of its beak – a feature found in all raptors which helps them to hold prey and tear into carcasses.

The research team’s conclusion that the animal did not have talons “[adds] ammunition to the herbivory diet hypothesis”, Mr Tucker told BBC Nature.

“A more likely scenario [than being a carnivore] would be a gentle Diatryma that used its beak to harvest foliage, fruits, and seeds from the subtropical forests that it inhabited,” Mr Mustoe added.

The team believe that the similarities ofDiatryma to those of the carnivorous South American Phorusracids or “terror birds” led early palaeontologists to assume that the two were ecologically similar.

According to the study: “The common belief that Diatryma… was likewise a carnivore is more a result of guilt by association than actual anatomical evidence”.

Source:BBC

 

 

Review highlights role of citizen science projects.

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A review of more than 230 “citizen science” projects says the involvement of volunteers offers “high value to research, policy and practice”.

It added that such schemes had the potential to help meet the demands of monitoring the UK’s environment.

The review’s authors also produced a guide offering advice on how to get the most out of citizen science projects.

The review and guide was commissioned by the UK Environmental Observation Framework (UK-EOF).

The authors, from Nerc Centre for Ecology and Hydrology (CEH) and the Natural History Museum, London, reviewed 234 projects – ranging from small one-off local surveys to large-scale long-term programmes.

‘Cost effective’

“Participation with environmental science and natural history has a long history, especially in Britain, long before it was termed ‘citizen science’,” project leader Dr Helen Roy, an ecologist from the CEH, told BBC News.

“However, the development of communication technologies through the internet offers many new options which will help even more people to get involved in contributing information for monitoring our environment, which is under increasing pressure.”

The review reached a number of conclusions about the value of data collected by volunteers:

  • The development of technologies was “revolutionising citizen science”, for example through online recording and smartphone apps;
  • Data quality could be excellent, but was not fully recognised by all researchers or policymakers;
  • It is a cost-effective way of collecting environmental data
  • There was potential to make considerably more use of citizen science that currently was the case.

The guide, published alongside the review, offers the scientific communityadvice on how to develop, implement and evaluate citizen science projects.

The guide’s lead author, Dr John Tweddle from the Natural History Museum, said participating in the monitoring and observation was a “fun and rewarding pastime” for volunteers.

“Our guide aims to support anyone with an interest in developing their own citizen science project – and new communication technologies, like mobile phone apps and environmental sensors, mean that it has never been easier to get involved.”

Source:BBC

 

ADHD treatment ‘may reduce risk of criminal behaviour’.

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People with attention-deficit hyperactivity disorder who are involved in crime are less likely to reoffend when on treatment than not, a Swedish study shows.

Earlier studies suggest people with ADHD are more likely to commit offences than the general population.

Providing better access to medication may reduce crime and save money, experts and support groups say.

Researchers say the benefits of the drugs must be weighed against harms.

In the UK 3% of children have a diagnosis of ADHD, with half of them continuing to have the condition in adult life.

People with the disorder have to deal with problems with concentration, hyperactivity and impulsiveness.

Estimates suggest between 7-40% of people in the criminal justice system may have ADHD and other similar disorders, though in many cases the condition is not formally recognised.

We want people to have personal choice…no one is trying to force people to take drugs”

Researchers from the Karolinska Institute looked at data from over 25,000 people with ADHD in Sweden.

Less impulsiveness

They found people with ADHD were more likely to commit crime (37% of men and 15% of women) than adults without the condition (9% of men and 2% women).

The study published in the New England Journal of Medicine found when people took their medication they were 32-41% less likely to be convicted of a crime than when they were off medication for a period of six months or more.

Dr Seena Fazel, an author of the study and from Oxford University, says medication may reduce impulsive choices and may enable people to better organise their lives – allowing them to stay in employment and maintain relationships.

Co-author Prof Paul Lichtenstein says: “It is said that roughly 30 to 40% of long-serving criminals have ADHD. If their chances of recidivism can be reduced by 30%, it would clearly effect the total crime numbers in many societies.”

‘Personal responsibility’

Prof Philip Asherson, a psychiatrist and president of the UK Adult ADHD network, who was not involved in the study says: “We want people to have personal choice and personal responsibility – no-one is trying to force people to take drugs.”

He points out it costs £100-£300 a month to provide medication for someone with ADHD, and taking into account the costs of unemployment and the criminal justice system, these would “vastly outweigh” the costs of medication, he says.

The authors caution that the side effects of the drugs used, such as Ritalin, must be taken into account.

“There are of course a lot of people with ADHD in the population who are not involved in crime.

“But for some people with the condition – if you don’t treat them, they will try to treat themselves with street drugs,” says Andrea Bilbow, founder of the National Attention Deficit Disorder Information and Support Service, Addis.

“A referral to specialist adult services can cost £1,500 – compare this with the amount of money you can save if you keep people out of prison – it’s a no brainer.”

‘Better support’

The researchers looked at a variety of crimes – from petty crime to violent crime, finding a reduction in all of these when people took medication.

They acknowledge when offered medication, individuals may also get more attention from other support services – this could contribute to the reduction in criminal behaviour.

Prof Sue Bailey, president of the Royal College of Psychiatry, welcomes the study saying it “reminds us in an era of psychological therapies that medication can have a positive impact too”.

The authors of the study point out ADHD can exist alongside other conditions such as conduct disorders, calling for further work to untangle the contribution these may make to criminal behaviour.

They feel the Swedish findings are applicable to the UK and much of Western Europe where rates of ADHD in children and the medication prescribed are broadly similar.

Source:BBC