The title doesn't match the paper though. People had already decoded the bird calls. What the paper was giving evidence to was that the birds themselves are cognitively decoding the calls.
I’m glad we’re doing this research. It makes me wonder how much time and potential we’ve wasted over the years actively assuming non-human animals were just rote automatons.
It seems like a meaningful amount of science has been spent on systematically dismantling pre-existing prejudice over the last hundreds of years (and thousands in some cases and cultures).
All humans are human.
Babies can feel pain.
Plants feel.
Animals think.
Just …
So much wasted time on what should have always been seen as true.
I get that some cultures already thought some of these things, but many of these were sadly not prevailing.
Yeah I think there's a lot of science news about how plants are capable of more than the average person thinks, but people tend to conflate that with some kind of conscious experience.
fortunately, there is a lot of evidence behind plant's feeling and thinking; enough so that if you were to expose yourself to it, and if you were willing to update your beliefs based on strong scientific evidence, I believe you'd change your view.
11 distinct calls is something a rote automaton could easily cope with. So I don't think this study proves much of anything about birds' cognitive abilities.
I work in the field. The main takeaway is zebra finches (maybe other songbirds) can discriminate vocalizations based on function, even if they sound similar.
Generally, birds can tell apart categories of sounds e.g. vocalizations from different individual birds, male vs female, call vs song, conspecific vs heterospecific etc. The question is if birds can do it for specific function e.g. agonistic calls vs non-agonistic calls. Simple question but way harder to test because of associated contextual info. with vocalizations.
The paper is culmination of last decade of work (includes many of the past works) but this is the new result.
> the birds mistook long-distance contact calls and short-distance contact calls, which are acoustically very different. But, they never mistook a short contact call with a short alarm call, which have very similar acoustic patterns but entirely distinct meanings. As such, the study reveals that call perception elicits a mental imagery of the meaning of call-types, rather than triggering a reflexive response.
Generally, you test birds in a series of discrimination experiments. So for this example, the discrimination task would be distance calls vs contact calls. Let's say, birds learn to discriminate between 20 distance calls vs 20 contact calls. They can learn this quickly (reward and punishment). After birds learned this rule (say 75% accuracy), we ask to generalize this by adding more calls. Now, birds have to discriminate 30 distance calls vs 30 contact calls (10 new for each). We can check now, for which new calls they are more likely to correct and incorrect response.
In this research field, we often perform this types of experiments (not this exact one). So, this is not that surprising to some of us. Birds also prioritize duration a lot when telling apart calls.
Interesting! Could you break this down further? Maybe specific examples of what you're mentioning might help - for instance, what "similar-sounding calls with different functions" are zebra finches discriminating between? What exactly are different situations of these functions? How exactly (and through what experiments) did she determine this?
And I read the article (but not her research paper), and have a vague idea, but it's tough to get a full grasp - and if this is just too difficult to fully explain, no worries!
Yeah, the paper is indeed difficult to read (even for me). I read it a while back. I'll try to explain.
So, there are few things to know before and see what we're trying to prove. main thing: Categorical perception: (in short) brain perceive similar sounding sounds (say A and B) in a continuous manner, and in the continuum of two sound, there would be a point where one sound (A) will switch and sound like the other sound (B).
In zebra finches, let's take an example: distance call and tet call. Both these calls are contact calls, birds use them to keep in contact with other birds.
Now, we need to extract the acoustic similarity between these two calls, and test birds in a experiment where we ask them to discriminate between these two call types (and get a learning curve; say trials vs probability of correct choice). Then, we can fit a theoretical model of categorical perception to see how well they fit both in acoustic and perceptual dimensions.
This is for one function (contact call), we can do this within other call types and between other call types. At the end, we can see how much of birds' performance is explained by acoustic dissimilarity, function of acoustic calls etc.
This is what the authors have done. They first performed LDA based classification on call type to obtain distance between call types, misclassification etc. (acoustic dimension). Birds went through a series of discrimination experiments based on call types (similar to what wrote above). Then, they compared/matched acoustic and perceptual dimension.
Thanks for the explanation on this. Think I partially understand. Birds can distinguish calls on at least two characteristics, by the sound of it and by its function. And the authors have developed experiments to show that birds can do both. Is this correct or did I get on the wrong track?
Yes. Kind of. They showed that birds can do function/meaning of calls (e.g., contact call group) using the meaning not other cues (e.g. duration, acoustic similarity of calls etc.).
A lot of interesting information here, but this one paragraph blew my mind:
> Although the birds occasionally made mistakes, they more often confused calls with similar meanings rather than similar sounds. “Their responses indicated they have a mental imagery of the meaning of their vocalisations,” Elie said. “In other words, that they understand the meaning of their call types.”
I remember hearing about an interesting paper; it argued that Zebra finch songs were as complex as recursively enumerable languages on the Chomsky hierarchy. I wanted to see if I could find it but came across another paper arguing that their embedded context sensitivity can be explained by simpler rules.
https://www.pnas.org/doi/10.1073/pnas.0908113106
Just the same, these little fellows are some of the cutest on our planet.
Left this comment as another computer science connection.
I started feeding a local murder of crows earlier this year.
They seem to have distinctive two-caw sounds for “human sighted, food is about to be thrown”, a “food is here, no sign of the human” and finally, a “human, we’re here, you coming out to throw us some scraps?”
They make plenty of other calls too, but I haven’t been able to associate those with anything I’ve observed them doing.
I may just be over anthropomorphizing, but I’ve recorded them and those three dual-caw calls sound subtly different (to my untrained ears). I’m certain actual ornithologists have looked into this. Chances are, though, I may be suffering from “I want to believe” syndrome.
Coller foundation press release: https://www.jeremycollerfoundation.org/news-and-insights/pre...
The actual publication in Science: https://www.science.org/doi/10.1126/science.ads8482