Fruit flies with free will
Matt sez, "A researcher at my University is working on modeling the behaviour of fruit flies. Turns out they have something like a Free Will, or at least they are not completely random in their flying patterns. Check out the video of drosophila in the flight simulator."
Their results caught computer scientist and lead author Alexander Maye from the University of Hamburg by surprise: “I would have never guessed that simple flies who keep bouncing off the same window otherwise have the capacity for nonrandom spontaneity if given the chance.” Previous studies have shown that in nature, flies do not buzz about aimlessly but forage according to a sophisticated search strategy (this is how they find our wine glasses). The new research now suggests that such strategies arise spontaneously rather than being induced by spatial cues.Link (Thanks, Matt!)
the latest
latest episodes
I've often wondered how a fly, after being shooed away, can zig-zag around the room only to return to the exact same spot time after time. There must be some pretty nifty navigational hardware and software encapsulated inside that tiny head!
C'mon, behaviour that appears to be purposeful is not the same thing as free will. Ants follow a sugar trail. Human males buy more of products advertised with images of attractive women. There's no need for any magical para-physical ego or soul sitting inside the flies' heads pulling levers and telling them what to do. I recommend a dose of Daniel Dennett - not exactly light reading, but on my shelf next to Dawkins and Skinner.
This makes me think of those programmable toy cars where you'd press buttons to add commands that made if go forward, turn, or reverse for a short time. You could make them navigate through a room, but if their starting position was off they'd bounce off walls and act completely random. You know, like a fly bouncing off the same window repeatedly.
This seems like the exact opposite of free will. The flies have a program in their noggins, optimized by randomization and selection for largest set of environments they tend to deal with, with some small amount of sensor input.
I'd go so far as to hypothesize that a farm house that's been mostly unchanged for many many years probably has flies that navigate it better than non-local flies.
Yeah, I actually read the article now. I suppose couching research on fly behavior in a discussion of free will is a great way to publicize what is, on its own, a fairly interesting discovery.
I'm still failing to see how this contradicts the idea of a program. It happens to not have arbitrary constraints that a human programmer would use for simplicity and sanity. Maybe I'm just confused by how surprised some react when we're reminded (once again) that analogies aren't perfect.
It also seems like we're looking for the pot of free will at the end of the rainbow, but I suppose I support it as long as we get to enjoy the scenery on the way. Guess it's harder to get funding when you tell people you're trying to figure out how to reduce them to an algorithm. :)
I think at least metaphorically you could call this free will, I mean what is free will anyway? People are pretty predictable, and people that arent' are considered unstable. Free will comes up very seldom in people's lives, imagine if you had to think through and decide about everything that you did, you'd never get anything done. We all run on algorithms and you could characterize free will as the ability to recognize, alter, and create new ones.
I don't want this to sound mean, Slida, but at that point aren't you just slapping the "Free Will!" label on some bit of machinery in your head and patting yourself on the back?
I guess the real impetus behind the question of free will is people want to feel special, and the idea that someone could build a computer that could predict them makes them feel less so. But either the answer is 'no' due to quantum randomness, or 'yes' with enough computational power. It's an interesting topic worthy of investigation on its own, but asking about free will is just shoving your head between a rock and a hard place.
Why make yourself feel bad just because you are *merely* a fantastically complicated being in profoundly varied and rational universe?
Hmm.. I'm highly sceptical.
In their paper they say when they analyze the flight patterns that they find a fractal order, resembling Levy flights, which are a type of a random walk (http://en.wikipedia.org/wiki/L%C3%A9vy_flight).
Other examples include earthquakes... so, earthquakes have free will too???
As someone said above, it seems more likely they've evolved the most efficient system for getting where they're going without getting swatted - ie a directed random walk.
Now as to how they work out where they want to go, THAT's another question.
I agree with gtmoogle in that the blog seems to misrepresent an interesting study of fly behavior as some sort of statement on free will.
I am much more surprised when we find out the opposite: that we can accurately model ant 2-D navigation using four or five variables. I guess insect 3-D navigation is a tougher nut to crack.
Certainly a good spin to take when you get negative results, probably not a refutation of Calvin.
I don't know about the patting my self on the back part, but other than that, yeah that's exactly what I'm doing. Slapping 'free will' onto a mechanism. I'd never actually thought of it like that until I read this article. I don't actually believe that people have 'free will' in any idealogical sense of the term, so instead of just saying "I think 'free will' is bullshit, anyway.", I said what's thought of as 'free will' is just this mechanism, and that the capabilities and complexities of utilizing this mechanism, the things we can do with it are so much greater that mapping 'fruit fly free will' onto 'human free will' can really only be done metaphorically to make sense of the connection. Doesn't mean I'm right, of course.
Only goes to prove...
Time flies like an arrow, fruit flies like an orange.
JG
###
good Republican flies, corrupted by that Suzuki fellow no doubt. These things take generations to show.
@6 GTMOOGLE who said "Why make yourself feel bad just because you are *merely* a fantastically complicated being in profoundly varied and rational universe?"
Ahh, that's fine meta-narrative. A rose with mallic acid ferment sparkle, complex character and a fine oaky finish. Determinism and and fun, mixed all up akimbo.
I'm the senior author of the study and Matt was one of my students in a course on neuroinformatics this past term.
There are some very good points raised in the comments so far, especially the ones by gtmoogle and slida.
We were very careful not to raise the issue of free will in the original research article. There are currently three different levels at which "free will" is discussed.
(1) One is the dualistic free will in which our will exists independently of our brains. This, of course is an outdated view. Our choices are made by us, i.e. our brains and hardly any neurobiologist still holds a dualistic view any more. So that's not what we're talking about.
(2) The second is our own subjective experience of free will. Why do we have this strong feeling of authorship and how does the brain generate this feeling? For obvious reasons, that's not the level we are talking at, either.
(3) The reason for our subjective feeling of free will and authorship: is the brain just a complicated robot that works according to fixed rules and any variability is simply just noise as in a radio tuned between stations? Or is the variability that we see actively generated by the brain and not just some random by-product of inevitable noise? This is the level we address with our study. What we find is that already fruit flies have evolved brains which actually appear to generate more variability than they would if their brains had evolved to be as precise as possible. In other words, already flies are less precise and more fuzzy than they would technically need to be, from a technical point of view. Biological organisms are not engineered. There are many reasons why this has evolutionary advantages. Probably one of the easiest ones to cite would be, that it is more difficult for predators to catch the fly, if it makes unpredictable turns and at the same time, the fly can still head for a safe place and is not just flying randomly anywhere. There's a third way between deterministic and random and that's the one the flies are taking.
The most straightforward implication of our mathematical results is that individual fly behavior will never, in principle, be fully predictable, only probabilistically. Similar to quantum mechanics, individual behavior is fundamentally indeterminate and the reason is not chance, but the inherent property of brains to always do the same thing slightly differently.
IMHO, this is as close as biologists can come to scientifically address the old question of free will: how can the brain produce different behavior under identical circumstances? Our data show that even the simple brains of flies can have several behavioral options in the same situation - so I think it is likely that humans also always have a choice (as long as they have intact brains).
The distinction between "random" and "probabilistic" is a very fine one, but it decides how research into the biological workings of choice will progress. As such, our study showed us in what direction we need to focus our attention when we now start to investigate the brain areas generating variable behavior.
Just last Friday a camera team from JoVE was in my and Alexander Maye's (one of the collaborators) lab to shoot the technical details of our study. With the JoVE publication, we will release our entire set of raw data as well as the source code for the mathematical evaluation free for anybody to reproduce our results. So keep your eyes on JoVE for the full and open scoop of this research.
Brembs -
Thank you, that was fascinating reading.
I'm still stuck on the phrase "nonrandom spontaneity." Is it just me or is that an oxymoron? If something is spontaneous then it is difficult or impossible to predict and that's random. If something is predictable, you could say that it was nonrandom, but then it wouldn't be spontaneous.
Thanks for the post Brembs! It sounds like great research. I'm curious about precision vs flexibility. Any thoughts on analyzing the spontaneity of flies that live in different environments, and of one verses many generations in them?
For my own part, I'll try to rein in my cynicism a bit. It was probably a bit uncouth of me to project motives onto others.
ruzel, the behavior of nonlinear systems is very difficult to predict, but it's not random. There is a gradient in predictability where "random" and "determined" are just the endpoints.
So nonrandom spontaneity is not an oxymoron.
gtmoogle, in our research article, we have analyzed the spontaneous behavior of flies in three different environments and have found that despite the behavior being very different to the human eye, the same nonlinear signature could be detected. So quantitatively, the behavior is different in different environments, but qualitatively it remains very similar. This is reminiscent of what people see when they image the human brain using fMRI: spontaneous activity during idle time, which changes (but is still there) when we engage in a task.
I'm sure our evaluation algorithms will be used on other animals in the future as well, not only on different generations of flies (which we will have to do anyway, when we look for the brain areas which generate spontaneous behavior).
After a bit of pondering this morning, I'll reel out a little more cynicism.
Why is it that spontaneity is considered such a huge factor in the "feeling of free will and authorship"? I'm not well versed in the related philosophy, but I am honestly curious.
It seems to me that any definition of free will should include how people feel a sense of control over things that really are random or uncontrollable.
For examples familiar to those around here, putting up a bag of water on what happens to be a windy day will still let people feel in control ( http://www.boingboing.net/2008/04/15/water-filled-plastic.html#comment-165781 ). The article linked by http://www.boingboing.net/2008/04/15/timelapse-video-of-m.html also mentions that the close-door buttons in elevators haven't done anything in over 10 years, yet people persist in pushing them.
(I really wish I could find a reliable reference for the cut corpus callosum experiment where the subject was told to stand, and when asked why he stood explained he was thirsty)
It seems from this aspect that free will is an illusion of control despite randomness. Humans should be expected to have a sense of authorship despite spontaneity of decisions. Cognitive dissonance has certainly never been a barrier.
GTMOOGLE - you open up a whole new can of worms here! Right on the spot. Control is also one of my major research interests as it is the effect of learning to use the consequences of spontaneous behavior (i.e., operant learning).
Once operant learning ha evolved, feeling in control evolved to be rewarding by itself, even in flies: if flies are allowed to chose between a situation of full control or reduced control, they choose the full control version.
Obviously, there's a lot of research going on in this respect and "free will" in my opinion is a much too narrow term to fit all that in, even though some of that factors into what we commonly call or experience as free will.