Fruit flies show mark of intelligence in thinking before they act

May 22, 2014
Drosophila sp fly. Credit: Muhammad Mahdi Karim/Wikipedia

Fruit flies 'think' before they act, a study by researchers from the University of Oxford's Centre for Neural Circuits and Behaviour suggests. The neuroscientists showed that fruit flies take longer to make more difficult decisions.

In experiments asking to distinguish between ever closer concentrations of an odour, the researchers found that the flies don't act instinctively or impulsively. Instead they appear to accumulate information before committing to a choice.

Gathering information before making a decision has been considered a sign of higher intelligence, like that shown by primates and humans.

'Freedom of action from automatic impulses is considered a hallmark of cognition or intelligence,' says Professor Gero Miesenböck, in whose laboratory the new research was performed. 'What our findings show is that fruit flies have a surprising mental capacity that has previously been unrecognised.'

The researchers also showed that the gene FoxP, active in a small set of around 200 neurons, is involved in the decision-making process in the fruit fly brain.

The team reports its findings in the journal Science. The group was funded by the Wellcome Trust, the Gatsby Charitable Foundation, the US National Institutes of Health and the Oxford Martin School.

The video will load shortly.
In this video the two lead authors, Shamik DasGupta and Clara Howcroft Ferreira, explain the work and its significance. Credit: Centre for Neural Circuits and Behavior, University of Oxford

The researchers observed Drosophila fruit flies make a choice between two concentrations of an odour presented to them from opposite ends of a narrow chamber, having been trained to avoid one concentration.

When the odour concentrations were very different and easy to tell apart, the flies made quick decisions and almost always moved to the correct end of the chamber.

When the odour concentrations were very close and difficult to distinguish, the flies took much longer to make a decision, and they made more mistakes.

The researchers found that mathematical models developed to describe the mechanisms of decision making in humans and primates also matched the behaviour of the fruit flies.

The scientists discovered that fruit flies with mutations in a gene called FoxP took longer than normal flies to make decisions when odours were difficult to distinguish – they became indecisive.

The researchers tracked down the activity of the FoxP gene to a small cluster of around 200 neurons out of the 200,000 neurons in the brain of a fruit fly. This implicates these neurons in the evidence-accumulation process the flies use before committing to a decision.

Dr Shamik DasGupta, the lead author of the study, explains: 'Before a decision is made, collect information like a bucket collects water. Once the accumulated information has risen to a certain level, the decision is triggered. When FoxP is defective, either the flow of information into the bucket is reduced to a trickle, or the bucket has sprung a leak.'

Fruit flies have one FoxP gene, while humans have four related FoxP . Human FoxP1 and FoxP2 have previously been associated with language and cognitive development. The genes have also been linked to the ability to learn fine movement sequences, such as playing the piano.

'We don't know why this gene pops up in such diverse mental processes as language, decision-making and motor learning,' says Professor Miesenböck. However, he speculates: 'One feature common to all of these processes is that they unfold over time. FoxP may be important for wiring the capacity to produce and process temporal sequences in the brain.'

Professor Miesenböck adds: 'FoxP is not a "language gene", a "decision-making gene", even a "temporal-processing" or "intelligence gene". Any such description would in all likelihood be wrong. What FoxP does give us is a tool to understand the brain circuits involved in these processes. It has already led us to a site in the brain that is important in decision-making.'

Explore further: Scientists identify the switch that says it's time to sleep

More information: "FoxP influences the speed and accuracy of a perceptual decision in Drosophila," by S. DasGupta et al. … 1126/science.1252114

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2.3 / 5 (3) May 22, 2014
The title is misleading, flies don't "think". The article states it much better, they have subroutines in their bio-mechanical computers that collect data and are triggered if the software conditions are satisfied.
May 22, 2014
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4.2 / 5 (5) May 22, 2014
The title is misleading, flies don't "think". The article states it much better, they have subroutines in their bio-mechanical computers that collect data and are triggered if the software conditions are satisfied.

I sometimes wonder if this type of thinking is something that evolved from religious dogmas about only humans having a soul...
Of course flies have consciousness and primitive form of "thoughts" and decision making.
Obviously our brains are enormously more complex than those of flies, but I think the basics: consciousness, thinking, memory, and mental projection of sensory information is there. Just in a much, much more primitive form.
It is something that has evolved from very primitive lifeforms to the minds we posess today as human beings.
The brain of a fly is certainly not a computer. No more than the brain of human. The greatest difference between a computer and a living being is consciousness.
May 22, 2014
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not rated yet May 23, 2014
If they're like me they think "what the hell did I come in here for?"
not rated yet May 23, 2014
Pure reflexes cannot explain their behavioral strategy.

Why not?

Mere appeals to apparent complexity aren't very strong arguments because it's simple to create a system that procedurally generates incredibly complex behaviours out of a simple dumb system. Such as:


A fruit fly might find it a competetive advantage to generate some sort of hard-to-predict pseudo-random behaviour that on the outside looks purposeful and intelligent because you haven't watched it for long enough to see a pattern unfold. In fact, you may need to spend the entire time of the universe to see it repeat itself, but it's still just a perfectly dumb circuit that will, when seeded with the same starting value, repeat the same motions without fail.

Reflexes combined with a bit of random noise can so create behaviour that seems purposeful even in very simple systems, and this is employed a lot in game AI that are very very simple indeed.
1 / 5 (1) May 23, 2014
No, zscientist, I completely reject that any animal that is not self aware has a "consciousness", and that includes higher animals. It appears that a minimal amount of the self-aware behavior appears in only one bird, but below that there is no recognition. If an animal doesn't even know "itself" exists, then it is just a bundle of software, some behaviors built in, some reacting to their environment.
not rated yet May 23, 2014
Our brains are more complex than any computer. Build a computer more complex than our brain and you may have a Skynet ala Terminator.
not rated yet May 24, 2014
If an animal doesn't even know "itself" exists, then it is just a bundle of software, some behaviors built in, some reacting to their environment.

A computer program can be encoded with the information about its own existence just as well.

The question is, is the program intelligent, because if it's not then it doesn't actually understand anything of what it's doing or what it knows, therefore it cannot have a self because the information it has is just meaningless symbols to a dumb machine.

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