6 ms·

Puts on critic hat The article is making a claim that can be summarized as... the cognitive capacity to share with conspecifics something learned more than 12

Puts on critic hat The article is making a claim that can be summarized as... the cognitive capacity to share with conspecifics something learned more than 120 seconds ago, is unique to humans and orangutans They also inform you that bees have this capacity. That should be enough to make anyone skeptical. It seems like they identified a particular behavior unique among apes to Orangutans - suppressing vocalization in response to threat - ran an experiment to confirm their bias, and are spinning it as a story about the ability to talk about the past (rather than simply that Orangutans have evolved to deal with perceived threat by keeping quiet while the threat is present, and then going bananas after it's gone). Conveying info about the past is something bees can do; yet it escapes Chimps and Bonobos. Yeah, ok.

twimbley 8y ago
So you're idea is that lots of living things innately perform this sort of skill, and that choosing to look at from a certain perspective lends the impression that it's a hallmark of intellectual distinction, simply because they're choosing to look at things the wrong way? I think the idea is that it takes a bit more abstract symbolic thought to look at rival predators, then look at peers of the same species, and make eye contact and include a gesture that expresses a suggestion to stay hidden and keep quiet. If I hop a fence, hide from the cops, and then unexpectedly find you in the same place, also hiding, then for me to hold up my finger over my lips would represent my recognition of you as a fellow peer on the run also threatened with arrest and jail. That's a certain sort of interesting cognitive leap that I would not expect to see in most apes. If orangutans can do it, it's notable. I suspect you might see something like this in squid or octopoda. In bees, signaling dances aren't precisely the same kind of symbolic thought, because they don't have capacity to select what they dance about. It's a somewhat inflexible, robotic gambit of flowers, nectar, hive, honey, and nothing that deviates from the program, as complex as the program may be in its own right.
- mannykannot 8y ago
  This is the problem with regarding intelligence as just a collection of externally-observable behaviors. We simply don't know, at this point, the extent to which the orangutans are choosing this pattern of behavior as a result of considering the possible outcomes of the alternatives. As someone who spends a fair amount of time hiking in woodlands, I am familiar with the squeak of a chipmunk dashing for its burrow after spotting me, and I get the impression that they are silent if I have come close to them before they notice me. It is not difficult to posit how this pattern of behavior could arise from the interplay of a couple of related instinctive responses, and the same can be said for this orangutan behavior (though it does require the ability to remember a recent threat.) Whether there is more to it than that cannot be deduced from these observations.
  - nicoburns 8y ago
    True, but note that this is also true of observations about other humans. How do I know that the behaviour of other humans isn't just instinctive? I'd argue only assuming that mt experience is similar to theirs. I think it is far more reasonable to extend this line of thinking to orangutans, than it is to jave different standards for humans and other apes...
    - mannykannot 8y ago
      > How do I know that the behaviour of other humans isn't just instinctive? Ultimately, you don't. If you contemplate this sort of issue long enough, you will likely go through the three stages of solipsism: 1) What a ridiculous idea! 2) There must be a way to prove that this is wrong... 3) Occam, can I borrow your razor?
      - AstralStorm 8y ago
        By our definition, instinct is something automatic and available without training. Humans and at least some apes are known to exhibit an empathy instinct, potentially tied to presence of specialized mirror neuron networks and surrounding neural architecture. Even small children down to potentially neonates have it. Contrast to something that is higher level, like the ability to recognize a reflection in the mirror as yourself, which requires inference most likely, but part of it might operate as an instinct while another may be learned. (So it makes sense that it is appearing quite late in primate life.) Forming language might be an instinct, recognizing patterns, many kinds of learning.
Cybiote 8y ago
I agree with the general call for skepticism against the idea that displaced reference is so unique in the animal kingdom. Where I do not agree, is the implicit argument of "if a bee can do it then it's trivial". Within the animal kingdom, the sophistication of the honey bee's waggle dance, with predicates and combinable to a large number of phrases, is rare. The only other major example I can think of are primate calls. Bees are also highly intelligent; on a watt for watt, pound for bound basis, their only other rival might be the portia spider. Bees can communicate angles, distance and adjust for the movement of the sun when relaying these. They can learn abstract patterns and generalize. If you asked me which was more intelligent, the honey bee or the chicken, I'd be hard pressed to give an answer. https://en.wikipedia.org/wiki/Bee_learning_and_communication https://en.wikipedia.org/wiki/Bee_learning_and_communication
- subroutine 8y ago
  Ok, I'll ask - is a bird or a honey bee more intelligent? Before you answer, let me just say a few things... Pound-for-pound honey bees are indeed impressive. I actually didn't know all of those things, so thank you for sharing. Since I am no bee expert, I can only offer general principles. But yeah, that's a lot of fancy behaviors crammed into just ~1 million neurons; great optimization. However, with so few neurons, and so many programmed tasks, it leaves very little room for flexibility in their behavioral responses, which are likely to be exceptionally dependent on environment stability (see #1). I assume most people would include behavioral flexibility in their working-definition of intelligence. So it would make sense to consider not just the total number of behaviors an animal can perform, but also the degree of cognitive plasticity baked-in to the system overall. Birds also display an exceptional repertoire of behavior, despite their bird-brain (#2). Youtube has endless examples of birds doing incredible and hilarious things beyond flying and singing. For example I remember watching a few vids on Bowerbirds not too long ago, which build incredibly elaborate domiciles in an attempt to impress their lady friends; the ones making nests near urban areas were incorporating a lot of colorful man-made trinkets they scavenged from the big city to woo the ladies (which I think suggests some level of flexibility). Crows are even more impressive. These birds are so smart they get bored; and when they do, sometimes they like to fuck with other animals for entertainment (or so it seems). Also this: #3. I think chickens could potentially display similar highly adaptable behaviors; but they are written-off as nitwits because you often find them as the product of being stuffed into a cage for 18 hours a day, and all basic needs taken care of by humans. I hold the same prejudice to the rats in my lab (good for nothing idiot rats, can't learn jack, so lazy); until I see a rat in the wild and it's all athletic and reading books and stuff. All that said, I actually agree with your sentiment - that you cannot assume certain species are more or less intelligent than others, simply based on the relative sizes of their brain. However, if you take humans as the gold-standard for a highly intelligent species on Earth, and someone starts talking smack about our cousin being dumber than a honey bee, I'm going to take some liberties to make some sweeping generalizations of my own... but yeah, thanks for reeling me in on this. Apologies to the honey bee. #1. This is highly speculative, but behavioral inflexibility might be a contributing reason to the unprecedented rate of Colony Collapse Disorder we are seeing in western honey bees https://en.wikipedia.org/wiki/Colony_collapse_disorder https://en.wikipedia.org/wiki/Colony_collapse_disorder. #2."Birds are remarkably intelligent, although their brains are small. Corvids and some parrots are capable of cognitive feats comparable to those of great apes. Olkowicz, et al. (2016) "Birds have primate-like numbers of neurons in the forebrain". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4932926/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4932926/ #3. Parrot singing Drowning Pool song https://m.youtube.com/watch?v=uguXNL93fWg https://m.youtube.com/watch?v=uguXNL93fWg
vbuwivbiu 8y ago
why not ? What's to say that mental computations can't come in discrete units ? Maybe communication about the past is a self-contained computation that can evolve independently in brain networks as diverse as those of bees, orangutans and humans
- subroutine 8y ago
  It's not impossible, just highly improbable given everything we know about population genetics and behavioral neuroscience. It seems their claim is based on a single behavior that was selected because they observed it during field study and found it interesting. They confirmed the behavior in their experiment; this itself would have been an interesting report. To make a Science paper out of it though, it needed to be framed as a study about some uniquely human capacity (since we can't get over ourselves, and love being reminded of our big brains). However, as far as uniquely human cognitive capacities go, I've not heard of this one yet. And seemed like a pretty outlandish claim given my Australian Shepard will paw at a basket containing her leash while looking at me - which seems very much like she is trying to convey to me some info she learned in the past.
  - vbuwivbiu 8y ago
    and I guess delayed signalling implies mental time travel and consciousness, which being special and mysterious to us implies an expensive process - but maybe consciousness isn't expensive, and maybe it can be of only certain discrete things (like whatever bees might be conscious of). Dogs like yours are undoubtedly conscious.
    - subroutine 8y ago
      Yea, I agree. It's plausible. To clarify, I'm not at all saying bees aren't capable of conveying learned information. My position is that you, me, my dog, birds, bees, orangutans... we all seem to have this capacity. In fact, it seems more like a ubiquitous capacity, than a uniquely human capacity. The authors of this paper don't agree though; instead they are promulgating the idea that "Orangutans are the only great apes besides humans to ‘talk’ about the past". Which directly implies that Chimps and Bonobos never refer to learned information in their conspecific communications. Maybe they don't engage in delayed warning calls after exposure to a predator, for whatever adaptive reason. Nevertheless, I'd bet the farm Chimps refer to episodic or declarative memories is some way/shape/form in some instances of communication (and I'll double down, given the criteria is only 2-minutes elapsed time since the referenced event took place).
netcan 8y ago
Social insects have a way of spoiling intelligence tests. The mirror test is a good example. To recognize yourself in mirror, you need to understand that you are a person. Not many animals recognize themselves: apes, some ravens, elephants dolphins... all usual suspects known to be intellegnt. Give them a mirror and once they figure it out they spend the next hour making faces and checking out their own ass. Mark their face and they'll try to clean it in the mirror. Then ants. Ants seem to get mirrors too. So either ants are self conscious or the test is no good.
- AstralStorm 8y ago
  Getting how the mirror works is different from recognizing the object in the mirror as the image of yourself. The test has come trouble differentiating between the two. E.g. the ant might perceive the mirrored marked ant as another ant which would reasonably well fool this test.
  - sjeohp 8y ago
    They controlled for that using transparent glass with real ants on the other side. https://www.udocz.com/read/are-ants-capable-of-self-recognition-pdf https://www.udocz.com/read/are-ants-capable-of-self-recognit...
- clarry 8y ago
  > Give them a mirror and once they figure it out they spend the next hour making faces and checking out their own ass. If you've good links, I'd be curious to see this.
WhompingWindows 8y ago
Bees aren't great apes, though. Doesn't the article make the claim that amongst the great apes, this is their finding?
progressiveweb 8y ago
Your argument that because bees display a similar behavior, that it's grounds to invalidate the credibility the people conducting this study of Orangutan's cognitive abilities is based on conjecture. You are conflating a reference to another intelligent species as evidence to support a counter view to a commonly agreed upon advanced cognitive capabilities of the Orangutan. A previous study shows Orangutans do indeed have excellent memories and are able to communicate with humans using commonly agreed upon visual symbols. Long past the 120 seconds. https://www.youtube.com/watch?v=kwslHICR7K4 https://www.youtube.com/watch?v=kwslHICR7K4 side-note: I feel that often, parent's comment gets a lot of likes, not for the validity of the argument but rather being contrarian for the sake of it. It's troubling because often it appears that they are providing commentary on an area totally unfamiliar and outside the usual field of expertise like engineering. Instead what I see is erroneously inferring logic based on the specific pieces mentioned without taking account in to the larger picture. These scientific studies are conducted not one off but to support previous widely held beliefs by the scientific community with vastly more focused experience on their topic of research, just wish that HN folks would give them a more credit and practice modesty. Some people on HN don't even bother reading journals or studies being posted here, instead they just blindly hop on the bandwagon with serious holes in the argument.
- subroutine 8y ago
  You've clearly mistaken my primary qualm. I'm not saying that Orangutans are not fully capable of the things these authors claim. Moreover, I'm not even saying bees aren't capable of conveying learned information. On the contrary, my position is that everything from bees to orangutans to humans have this capacity. In fact, I see this type of communication happening between lots of animals. It seems more like a ubiquitous capacity, than a uniquely human capacity. The authors of this paper don't agree though; instead they are promulgating the idea that "Orangutans are the only great apes besides humans to 'talk' about the past". This is FALSE In this article... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4350813/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4350813/ *Chimps used intentional gestures to coordinate with an experimentally-naïve human to retrieve hidden food. In each trial, Experimenter #1 hid a food item anywhere from 3 m to 26 m from the outdoor enclosure under natural cover (e.g. log, soil, leaves, branches) in a trial-unique location in the surrounding woodland, whilst the chimpanzee was watching. The experimenter hid the food and concealed any signs of the hiding place (e.g. breaking up of soil). The chimpanzee could not enter the woodland itself. In order to retrieve the food, the chimpanzee had to recruit the assistance of an uninformed person (Experimenter #2) and direct him to the food item. The chimpanzees dynamically and flexibly modified their intentional gestures in relation to the naïve experimenter's search efforts towards the hidden food, and successfully guided experimenter #2 to the food item. You can see in the supplementary videos that experimenter #1 finishes hiding the food at time 4:19... Screenshot of timestamps: http://bit.ly/ChimpsCanToo http://bit.ly/ChimpsCanToo The chimp doesn't greet experimenter #2 until after 4:30 (see same screenshot above). If Orangutans are the only great apes besides humans to ‘talk’ about the past, how the hell is this Chimp communicating with a human to retrieve food it saw buried at some time in the past?

twimbley 8y ago

So you're idea is that lots of living things innately perform this sort of skill, and that choosing to look at from a certain perspective lends the impression that it's a hallmark of intellectual distinction, simply because they're choosing to look at things the wrong way? I think the idea is that it takes a bit more abstract symbolic thought to look at rival predators, then look at peers of the same species, and make eye contact and include a gesture that expresses a suggestion to stay hidden and keep quiet. If I hop a fence, hide from the cops, and then unexpectedly find you in the same place, also hiding, then for me to hold up my finger over my lips would represent my recognition of you as a fellow peer on the run also threatened with arrest and jail. That's a certain sort of interesting cognitive leap that I would not expect to see in most apes. If orangutans can do it, it's notable. I suspect you might see something like this in squid or octopoda. In bees, signaling dances aren't precisely the same kind of symbolic thought, because they don't have capacity to select what they dance about. It's a somewhat inflexible, robotic gambit of flowers, nectar, hive, honey, and nothing that deviates from the program, as complex as the program may be in its own right.

mannykannot 8y ago
This is the problem with regarding intelligence as just a collection of externally-observable behaviors. We simply don't know, at this point, the extent to which the orangutans are choosing this pattern of behavior as a result of considering the possible outcomes of the alternatives. As someone who spends a fair amount of time hiking in woodlands, I am familiar with the squeak of a chipmunk dashing for its burrow after spotting me, and I get the impression that they are silent if I have come close to them before they notice me. It is not difficult to posit how this pattern of behavior could arise from the interplay of a couple of related instinctive responses, and the same can be said for this orangutan behavior (though it does require the ability to remember a recent threat.) Whether there is more to it than that cannot be deduced from these observations.
- nicoburns 8y ago
  True, but note that this is also true of observations about other humans. How do I know that the behaviour of other humans isn't just instinctive? I'd argue only assuming that mt experience is similar to theirs. I think it is far more reasonable to extend this line of thinking to orangutans, than it is to jave different standards for humans and other apes...
  - mannykannot 8y ago
    > How do I know that the behaviour of other humans isn't just instinctive? Ultimately, you don't. If you contemplate this sort of issue long enough, you will likely go through the three stages of solipsism: 1) What a ridiculous idea! 2) There must be a way to prove that this is wrong... 3) Occam, can I borrow your razor?
    - AstralStorm 8y ago
      By our definition, instinct is something automatic and available without training. Humans and at least some apes are known to exhibit an empathy instinct, potentially tied to presence of specialized mirror neuron networks and surrounding neural architecture. Even small children down to potentially neonates have it. Contrast to something that is higher level, like the ability to recognize a reflection in the mirror as yourself, which requires inference most likely, but part of it might operate as an instinct while another may be learned. (So it makes sense that it is appearing quite late in primate life.) Forming language might be an instinct, recognizing patterns, many kinds of learning.

Cybiote 8y ago

I agree with the general call for skepticism against the idea that displaced reference is so unique in the animal kingdom. Where I do not agree, is the implicit argument of "if a bee can do it then it's trivial". Within the animal kingdom, the sophistication of the honey bee's waggle dance, with predicates and combinable to a large number of phrases, is rare. The only other major example I can think of are primate calls. Bees are also highly intelligent; on a watt for watt, pound for bound basis, their only other rival might be the portia spider. Bees can communicate angles, distance and adjust for the movement of the sun when relaying these. They can learn abstract patterns and generalize. If you asked me which was more intelligent, the honey bee or the chicken, I'd be hard pressed to give an answer. https://en.wikipedia.org/wiki/Bee_learning_and_communication https://en.wikipedia.org/wiki/Bee_learning_and_communication

subroutine 8y ago
Ok, I'll ask - is a bird or a honey bee more intelligent? Before you answer, let me just say a few things... Pound-for-pound honey bees are indeed impressive. I actually didn't know all of those things, so thank you for sharing. Since I am no bee expert, I can only offer general principles. But yeah, that's a lot of fancy behaviors crammed into just ~1 million neurons; great optimization. However, with so few neurons, and so many programmed tasks, it leaves very little room for flexibility in their behavioral responses, which are likely to be exceptionally dependent on environment stability (see #1). I assume most people would include behavioral flexibility in their working-definition of intelligence. So it would make sense to consider not just the total number of behaviors an animal can perform, but also the degree of cognitive plasticity baked-in to the system overall. Birds also display an exceptional repertoire of behavior, despite their bird-brain (#2). Youtube has endless examples of birds doing incredible and hilarious things beyond flying and singing. For example I remember watching a few vids on Bowerbirds not too long ago, which build incredibly elaborate domiciles in an attempt to impress their lady friends; the ones making nests near urban areas were incorporating a lot of colorful man-made trinkets they scavenged from the big city to woo the ladies (which I think suggests some level of flexibility). Crows are even more impressive. These birds are so smart they get bored; and when they do, sometimes they like to fuck with other animals for entertainment (or so it seems). Also this: #3. I think chickens could potentially display similar highly adaptable behaviors; but they are written-off as nitwits because you often find them as the product of being stuffed into a cage for 18 hours a day, and all basic needs taken care of by humans. I hold the same prejudice to the rats in my lab (good for nothing idiot rats, can't learn jack, so lazy); until I see a rat in the wild and it's all athletic and reading books and stuff. All that said, I actually agree with your sentiment - that you cannot assume certain species are more or less intelligent than others, simply based on the relative sizes of their brain. However, if you take humans as the gold-standard for a highly intelligent species on Earth, and someone starts talking smack about our cousin being dumber than a honey bee, I'm going to take some liberties to make some sweeping generalizations of my own... but yeah, thanks for reeling me in on this. Apologies to the honey bee. #1. This is highly speculative, but behavioral inflexibility might be a contributing reason to the unprecedented rate of Colony Collapse Disorder we are seeing in western honey bees https://en.wikipedia.org/wiki/Colony_collapse_disorder https://en.wikipedia.org/wiki/Colony_collapse_disorder. #2."Birds are remarkably intelligent, although their brains are small. Corvids and some parrots are capable of cognitive feats comparable to those of great apes. Olkowicz, et al. (2016) "Birds have primate-like numbers of neurons in the forebrain". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4932926/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4932926/ #3. Parrot singing Drowning Pool song https://m.youtube.com/watch?v=uguXNL93fWg https://m.youtube.com/watch?v=uguXNL93fWg

vbuwivbiu 8y ago

why not ? What's to say that mental computations can't come in discrete units ? Maybe communication about the past is a self-contained computation that can evolve independently in brain networks as diverse as those of bees, orangutans and humans

subroutine 8y ago
It's not impossible, just highly improbable given everything we know about population genetics and behavioral neuroscience. It seems their claim is based on a single behavior that was selected because they observed it during field study and found it interesting. They confirmed the behavior in their experiment; this itself would have been an interesting report. To make a Science paper out of it though, it needed to be framed as a study about some uniquely human capacity (since we can't get over ourselves, and love being reminded of our big brains). However, as far as uniquely human cognitive capacities go, I've not heard of this one yet. And seemed like a pretty outlandish claim given my Australian Shepard will paw at a basket containing her leash while looking at me - which seems very much like she is trying to convey to me some info she learned in the past.
- vbuwivbiu 8y ago
  and I guess delayed signalling implies mental time travel and consciousness, which being special and mysterious to us implies an expensive process - but maybe consciousness isn't expensive, and maybe it can be of only certain discrete things (like whatever bees might be conscious of). Dogs like yours are undoubtedly conscious.
  - subroutine 8y ago
    Yea, I agree. It's plausible. To clarify, I'm not at all saying bees aren't capable of conveying learned information. My position is that you, me, my dog, birds, bees, orangutans... we all seem to have this capacity. In fact, it seems more like a ubiquitous capacity, than a uniquely human capacity. The authors of this paper don't agree though; instead they are promulgating the idea that "Orangutans are the only great apes besides humans to ‘talk’ about the past". Which directly implies that Chimps and Bonobos never refer to learned information in their conspecific communications. Maybe they don't engage in delayed warning calls after exposure to a predator, for whatever adaptive reason. Nevertheless, I'd bet the farm Chimps refer to episodic or declarative memories is some way/shape/form in some instances of communication (and I'll double down, given the criteria is only 2-minutes elapsed time since the referenced event took place).

netcan 8y ago

Social insects have a way of spoiling intelligence tests. The mirror test is a good example. To recognize yourself in mirror, you need to understand that you are a person. Not many animals recognize themselves: apes, some ravens, elephants dolphins... all usual suspects known to be intellegnt. Give them a mirror and once they figure it out they spend the next hour making faces and checking out their own ass. Mark their face and they'll try to clean it in the mirror. Then ants. Ants seem to get mirrors too. So either ants are self conscious or the test is no good.

AstralStorm 8y ago
Getting how the mirror works is different from recognizing the object in the mirror as the image of yourself. The test has come trouble differentiating between the two. E.g. the ant might perceive the mirrored marked ant as another ant which would reasonably well fool this test.
- sjeohp 8y ago
  They controlled for that using transparent glass with real ants on the other side. https://www.udocz.com/read/are-ants-capable-of-self-recognition-pdf https://www.udocz.com/read/are-ants-capable-of-self-recognit...
clarry 8y ago
> Give them a mirror and once they figure it out they spend the next hour making faces and checking out their own ass. If you've good links, I'd be curious to see this.

WhompingWindows 8y ago

Bees aren't great apes, though. Doesn't the article make the claim that amongst the great apes, this is their finding?

progressiveweb 8y ago

Your argument that because bees display a similar behavior, that it's grounds to invalidate the credibility the people conducting this study of Orangutan's cognitive abilities is based on conjecture. You are conflating a reference to another intelligent species as evidence to support a counter view to a commonly agreed upon advanced cognitive capabilities of the Orangutan. A previous study shows Orangutans do indeed have excellent memories and are able to communicate with humans using commonly agreed upon visual symbols. Long past the 120 seconds. https://www.youtube.com/watch?v=kwslHICR7K4 https://www.youtube.com/watch?v=kwslHICR7K4 side-note: I feel that often, parent's comment gets a lot of likes, not for the validity of the argument but rather being contrarian for the sake of it. It's troubling because often it appears that they are providing commentary on an area totally unfamiliar and outside the usual field of expertise like engineering. Instead what I see is erroneously inferring logic based on the specific pieces mentioned without taking account in to the larger picture. These scientific studies are conducted not one off but to support previous widely held beliefs by the scientific community with vastly more focused experience on their topic of research, just wish that HN folks would give them a more credit and practice modesty. Some people on HN don't even bother reading journals or studies being posted here, instead they just blindly hop on the bandwagon with serious holes in the argument.

subroutine 8y ago
You've clearly mistaken my primary qualm. I'm not saying that Orangutans are not fully capable of the things these authors claim. Moreover, I'm not even saying bees aren't capable of conveying learned information. On the contrary, my position is that everything from bees to orangutans to humans have this capacity. In fact, I see this type of communication happening between lots of animals. It seems more like a ubiquitous capacity, than a uniquely human capacity. The authors of this paper don't agree though; instead they are promulgating the idea that "Orangutans are the only great apes besides humans to 'talk' about the past". This is FALSE In this article... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4350813/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4350813/ *Chimps used intentional gestures to coordinate with an experimentally-naïve human to retrieve hidden food. In each trial, Experimenter #1 hid a food item anywhere from 3 m to 26 m from the outdoor enclosure under natural cover (e.g. log, soil, leaves, branches) in a trial-unique location in the surrounding woodland, whilst the chimpanzee was watching. The experimenter hid the food and concealed any signs of the hiding place (e.g. breaking up of soil). The chimpanzee could not enter the woodland itself. In order to retrieve the food, the chimpanzee had to recruit the assistance of an uninformed person (Experimenter #2) and direct him to the food item. The chimpanzees dynamically and flexibly modified their intentional gestures in relation to the naïve experimenter's search efforts towards the hidden food, and successfully guided experimenter #2 to the food item. You can see in the supplementary videos that experimenter #1 finishes hiding the food at time 4:19... Screenshot of timestamps: http://bit.ly/ChimpsCanToo http://bit.ly/ChimpsCanToo The chimp doesn't greet experimenter #2 until after 4:30 (see same screenshot above). If Orangutans are the only great apes besides humans to ‘talk’ about the past, how the hell is this Chimp communicating with a human to retrieve food it saw buried at some time in the past?