In science, no work is completed until it has been picked to pieces

Dangerous dithering.

What does a scientist have to do to convince you? The answer used to be “wait until his critics die” – hence the physicist Max Planck’s assertion that science advances one funeral at a time.

But sometimes even that is not enough. Late last month, the smell researcher Luca Turin published striking new evidence supporting an idea first put forward by Sir Malcolm Dyson in 1938. Dyson presented his “vibrational” theory of how our sense of smell works to universal apathy. Three generations later, scientists are still saying “meh”.

That year, 1938, was also when it was first argued that pumping carbon dioxide into the atmosphere would raise global temperatures. The idea came from the steam engineer Guy Stewart Callendar; the broad response was “implausible”. Today, in 2013, scientists have shifted: they generally agree that Callendar was right. Yet there remains a dangerous level of disagreement about the detail.

At least Turin’s scientific peers have presented him with a clear path to follow. Dyson’s idea was that when a molecule gets up our nose, its characteristic smell is created by the way the bonds within that molecule vibrate. In a clever piece of experimental work, Turin has shown that human beings can distinguish between two molecules that differ only in the way they vibrate. The two molecules tested were both cyclopentadecanone, but while one contained normal hydrogen atoms the other contained “deuterated” hydrogen, which has an added neutron in its atomic nucleus. The additional particle creates a difference in the way the molecules vibrate. And that is why, according to Turin, they smell different to us.

The experiment punches a hole in the accepted theory of smell, which says that smell experiences are triggered by differently shaped molecules fitting different receptors in the nose. This “lock and key” idea can’t explain why two identically shaped molecules smell different. But Turin’s critics said last month that before they will even consider accepting his theory, they want him to show exactly what goes on in human smell receptors.

They are right to make such demands. This is science, where no work is finished until it has been picked to pieces. But that is exactly why it has been so easy to do so little about climate change since 1938. Later this year, the Intergovernmental Panel on Climate Change will make some highly equivocal, backtracking announcements. In a report due for release in December, the IPCC will concede that we can’t be sure tropical cyclones will become more frequent, or that droughts will get worse. Worries that the Gulf Stream will collapse, tentatively raised in the 2007 IPCC report, are allayed: such an event is “unlikely” to occur in the foreseeable future.

Concern over details can have an unhelpful effect, masking the big picture on climate change – the one that Nicholas Stern, who wrote the UK government’s 2006 review on the science, said at Davos last month is “far, far worse” than we were led to believe originally. Until that, rather than the detail, becomes the focus, we can continue to dither over whether to do anything, let alone deciding what course we might take.

It does not matter a great deal that no one is willing to risk his career by backing Luca Turin – but to wait for absolute certainty over the details of climate change before we do anything about it will spell life or death for many. If science continues to advance one funeral at a time, its acceleration is assured; and there will be no shortage of funerals in a world that’s 4° warmer.

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 11 February 2013 issue of the New Statesman, Assange Alone

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Not just a one-quack mind: ducks are capable of abstract thought

Newborn ducklings can differentiate between objects that are the same and objects that are different, causing scientists to rethink the place of abstract thinking.

There’s a particular loftiness to abstract thought. British philosopher and leading Enlightenment thinker John Locke asserted that “brutes abstract not” – by which he meant anything which doesn’t fall under the supreme-all-mighty-greater-than-everything category of Homo sapiens was most probably unequipped to deal with the headiness and complexities of abstract thinking.

Intelligence parameters tail-ended by “bird-brained” or “Einstein” tend to place the ability to think in abstract ways at the Einstein end of the spectrum. However, in light of some recent research coming out of the University of Oxford, it seems that the cognitive abilities of our feathery counterparts have been underestimated.

In a study published in Science, led by Alex Kacelnik – a professor of behavioural psychology – a group of ducklings demonstrated the ability to think abstractly within hours of being hatched, distinguishing the concepts of “same” and “different” with success.

Young ducklings generally become accustomed to their mother’s features via a process called imprinting – a learning mechanism that helps them identify the individual traits of their mothers. Kacelnik said: “Adult female ducks look very similar to each other, so recognising one’s mother is very difficult. Ducklings see their mothers from different angles, distances, light conditions, etc, so their brains use every possible source of information to avoid errors, and abstracting some properties helps in this job.”

It’s this hypothesised abstracting of some properties that led Kacelnik to believe that there must be more going on with the ducklings beyond their imprinting of sensory inputs such as shapes, colours or sounds.

The ability to differentiate the same from the different has previously been used as means to reveal the brain’s capacity to deal with abstract properties, and has been shown in other birds and mammals, such as parrots, pigeons, bees and monkeys. For the most part, these animals were trained, given guidance on how to determine sameness and differences between objects.

What makes Kacelnik’s ducklings special then, as the research showed, was that they were given no training at all in learning the relations between objects which are the same and object which are different.

“Other animals can be trained to respond to abstract relations such as same or different, but not after a single exposure and without reinforcement,” said Kacelnik.

Along with his fellow researcher Antone Martinho III, Kacelnik hatched and domesticated mallard ducklings and then threw them straight into an experiment. The ducklings were presented pairs of objects – either identical or different in shape or colour – to see whether they could find links and relations between the pairs.

The initial pairs they were presented served as the imprinting ones; it would be the characteristics of these pairs which the ducklings would first learn. The initial pairs involved red cones and red cylinders which the ducklings were left to observe and assimilate into their minds for 25 minutes. They were then exposed to a range of different pairs of objects: red pyramid and red pyramid, red cylinder and red cube.

What Kacelnik and his research partner found was that the ducklings weren’t imprinting the individual features of the objects but the relations between them; it’s why of the 76 ducklings that were experimented with, 68 per cent tended to move towards the new pairs which were identical to the very first pairs they were exposed to.

Put simply, if they initially imprinted an identical pair of objects, they were more likely to favour a second pair of identical objects, but if they initially imprinted a pair of objects that were different, they would favour a second pair of differing objects similar to the first.

The results from the experiment seem to highlight a misunderstanding of the advanced nature of this type of conceptual thought process. As science journalist Ed Yong suggests, there could be, “different levels of abstract concepts, from simple ones that young birds can quickly learn after limited experience, to complex ones that adult birds can cope with”.

Though the research doesn’t in any way assume or point towards intelligence in ducklings to rival that of humans, it seems that the growth in scientific literature on the topic continues to refute the notions that human being as somehow superior. Kacelnik told me: “The last few decades of comparative cognition research have destroyed many claims about human uniqueness and this trend is likely to continue.”