Speaker 1: Welcome to Stuff to Blow Your Mind, the production of
Speaker 1: My Heart Radio. Hey, welcome to Stuff to Blow Your Mind.
Speaker 1: My name is Robert Lamb and I'm Joe McCormick. And
Speaker 1: today we're going to be starting on a series that
Speaker 1: has to do with animal feeding behaviors, but specifically what
Speaker 1: comes before the feeding itself. I got into this topic
Speaker 1: by wondering about a simple question, and it was are
Speaker 1: there any animals other than humans that cook their food?
Speaker 1: Because if if you look at the relationship that humans
Speaker 1: have with food versus the at least obvious relationships that
Speaker 1: we can see on the surface level between most wild
Speaker 1: animals and their food, there were some pretty stark differences.
Speaker 1: So you know, you watch like a grazing herbivore mammal
Speaker 1: that's eating grass or eating leaves, it doesn't seem like
Speaker 1: they're putting the vegetation through any kind of external processing.
Speaker 1: It's just there in the environment. They bite it, they
Speaker 1: chew it, and they swallow it. Though once they swallow it,
Speaker 1: of course, if you're talking about like you know, ruminant
Speaker 1: mammals or something, plenty of interesting things happened to the
Speaker 1: food after it has been processed, say by the teeth
Speaker 1: in the mouth, there might be multiple different interesting stages
Speaker 1: of digestion, but in that first stage, before the food
Speaker 1: reaches the mouth, there's not really anything complex going on
Speaker 1: that There's just some material in the environment that has
Speaker 1: nutritional value. The animal comes within reach of that food,
Speaker 1: they bite it, they chew it up, they swallow it,
Speaker 1: they just eat it. And if you compared that to
Speaker 1: all of the sometimes mind bogglingly complex stages of manipulation, combination,
Speaker 1: and alteration of raw plant and animal materials that go
Speaker 1: into making a standard human meal, even meals that we
Speaker 1: would perceive as kind of simple. Like if you think
Speaker 1: about all of the pre processing and alteration that goes
Speaker 1: into the foods that make a cheeseburger, the difference is overwhelming.
Speaker 1: Oh yeah, I mean even if you're I mean, you
Speaker 1: can go even simpler than that. I guess if even
Speaker 1: if you just you don't even take into accounts, say meat,
Speaker 1: because meat processing, especially something like a hamburger, Uh, there's
Speaker 1: a lot of there are a lot of grotesque details
Speaker 1: that go into that. But but just like thinking about yeah,
Speaker 1: like the bread, uh, the the you know, the vegetables,
Speaker 1: even you know, being prepared the various sauces. I mean
Speaker 1: all the things that go into it. Uh, it's it's
Speaker 1: it's quite a lot. And yeah, coming back to what
Speaker 1: you said earlier that we think about animals, we think
Speaker 1: about purely internal food processing and in human cuisine. Human
Speaker 1: cooking is the externalization of various processes um things that
Speaker 1: that that we we tend to imagine generally only take
Speaker 1: place within the bodies of animals. We found ways to
Speaker 1: do them externally to give our internal digestion of break
Speaker 1: as well as to make things that are otherwise inedible
Speaker 1: edible exactly right, and of course the central idea, the
Speaker 1: thing that most people think about when you say the
Speaker 1: word cooking is the narrow sense of cooking, meaning causing
Speaker 1: chemical and structural changes to food by the application of heat,
Speaker 1: specifically heating. Uh. This is one of the most common
Speaker 1: ways of processing food before we eat it. And this
Speaker 1: does exactly the things you're talking about. It takes foods
Speaker 1: that would not otherwise be edible to humans and makes
Speaker 1: them edible, or makes them safe to eat, or increases
Speaker 1: the availability of nutrition from the same starting quantities of food.
Speaker 1: So you take a mass of raw food, you cook it.
Speaker 1: You can usually increase its nutritional efficiency, you can get
Speaker 1: more nutrition out of it. And so to come back
Speaker 1: to the question of are there animals that cook, I
Speaker 1: would say, based on my research, if you're talking about
Speaker 1: on their own in the wild, it appears that the
Speaker 1: answer is no. In that narrow sense of cooking, meaning
Speaker 1: cooking by applying heat, it seems that humans are the
Speaker 1: only animals that do that in a consistent way. That
Speaker 1: we can talk about a few interesting wrinkles to that
Speaker 1: generalization in a minute. But when it comes to the
Speaker 1: broader sense of cooking, which is you could imagine anything
Speaker 1: that people would do in a restaurant kitchen or in
Speaker 1: a home kitchen, any way that people manipulate food or
Speaker 1: prepare meals other than by applying heat. It turns out
Speaker 1: non human animals do all kinds of fascinating things to
Speaker 1: their food before consuming it along these lines. And so
Speaker 1: that's what I wanted to talk about in this series.
Speaker 1: What do animals do that could be construed as cooking
Speaker 1: in one way or another, Even accepting that no animals
Speaker 1: in the wild cook their food with heat, well with
Speaker 1: the exception of the rat, to a phenomenon by which
Speaker 1: a rat uh once exposed to culinary traditions in an
Speaker 1: urban environment, will then begin to cook itself, um to
Speaker 1: to actually copy various recipes that are around it, improve
Speaker 1: upon those recipes, and sometimes crawl on top of a
Speaker 1: man's head and pull his hair to use said human
Speaker 1: as a puppet to move around the kitchen and prepare um,
Speaker 1: you know, fine works of French cuisine or yes I
Speaker 1: can't recall. Okay, yes, the ratitui itself. Yes, but it
Speaker 1: begs the question is this is this do we see
Speaker 1: this only with French cuisine or uh does the ratitui
Speaker 1: phenomenon um repeat itself in various other cultures? Animals can
Speaker 1: only be trained to make sauces that are heavy and dairy,
Speaker 1: So yeah, it is a French thing. Okay, But no,
Speaker 1: that's a good point because actually, by raising ratitui, you
Speaker 1: point out that I think you could quite clearly find
Speaker 1: plenty of examples of animals that have been trained in
Speaker 1: some sense to cook. Now, uh, they're probably never going
Speaker 1: to be as versatile as a human cook, but I'm
Speaker 1: sure you can find tons of examples of an animal
Speaker 1: that somebody trained to go turn on the micro wave
Speaker 1: or something like that, you know, to to boop at
Speaker 1: the oven knob with their nose until it comes on
Speaker 1: or something along those lines. And then of course it's
Speaker 1: the whole area of animals that are willing to benefit
Speaker 1: from cooking without having done it themselves. Like I once
Speaker 1: saw a seagull grab a hot dog half of off
Speaker 1: of a grill at the beach. Um. You know, the
Speaker 1: seagull was not itself barbecuing, but it was it was
Speaker 1: more than happy to benefit from the barbecuing. Well, that
Speaker 1: is a great point, and that actually feeds right into
Speaker 1: the next thing that I wanted to talk about. So
Speaker 1: before in this series we get into examples of animals
Speaker 1: doing some kind of cooking in the broader sense, meaning
Speaker 1: you know, preparing foods before they eat them in some
Speaker 1: way that doesn't involve the directed, uh application of heat.
Speaker 1: I do want to talk about cooked food in the
Speaker 1: narrower sense, food that has been heated. And one interesting
Speaker 1: place I thought to start there would be with the
Speaker 1: question in general, would non human animals actually prefer cooked
Speaker 1: food over the raw food stuffs that they would encounter
Speaker 1: in their natural environment. And it turns out there have
Speaker 1: been some studies that looked into this and in some
Speaker 1: cases there is a clear answer. So I wanted to
Speaker 1: start by looking at a paper published in the year
Speaker 1: two thousand and eight in the Journal of Human Evolution
Speaker 1: by Victoria Warber, Brian Hair, and Richard Wrangham called great
Speaker 1: Apes Prefer Cooked Food. Now, part of the background of
Speaker 1: this paper is based in the exploration of an idea
Speaker 1: that's come up in passing on the show a couple
Speaker 1: of times before. We've never actually devoted a full episode
Speaker 1: or series to it. Maybe someday we will. But it's
Speaker 1: what is known as the cooking hypothesis. And to summarize
Speaker 1: it briefly, the cooking hypothesis is the proposition that the
Speaker 1: advent of cooking was a major contributor to the physiological
Speaker 1: evolution of the ancestors of Homo sapiens. In other words,
Speaker 1: that a lot of things about the bodies of modern
Speaker 1: human beings are the way they are because our primate
Speaker 1: ancestors figured out how to control fire and how to
Speaker 1: cook their food by applying heat to it. Now you
Speaker 1: might wonder, well, how could our bodies be changed in
Speaker 1: an evolutionary sense by the invention of cooking. Well, essentially,
Speaker 1: it would happen by changing the pressures present in our
Speaker 1: nutritional regimes. So I think proponents of the cooking hypothesis
Speaker 1: usually argue that because cooked food is more nutritionally efficient,
Speaker 1: again meaning that if food is cooked, you take a
Speaker 1: food item you eat it raw versus you eat it cooked.
Speaker 1: In the cooked version, you can get more nutrition from
Speaker 1: it with less chewing, less energy spent on digestion, and
Speaker 1: so forth. Um, So, if suddenly eating and absorbing nutrition
Speaker 1: becomes easier and more efficient, we have to spend less
Speaker 1: time chewing, we have to spend less time gathering large
Speaker 1: quantities of food, The types of food we can eat
Speaker 1: safely is expanded, and we have to spend less energy
Speaker 1: developing large powerhouse, digestive tracts, and so forth. So perhaps
Speaker 1: other adaptive pressures fill the void, including bigger brains and
Speaker 1: so forth. And I think one proposed causal mechanism is
Speaker 1: that once cooking is invented, we can get more nutrition
Speaker 1: from the same amount of environmental material. Suddenly the carrying
Speaker 1: capacity of the local environment than is larger. There can
Speaker 1: be more humans per tribe, which requires bigger brains in
Speaker 1: order to maintain relationships with that larger number of humans.
Speaker 1: The main figure behind the cooking hypothesis is a British primatologist,
Speaker 1: and I think he either is now or it was
Speaker 1: at some recent point. Was it. Harvard Uh named Richard
Speaker 1: rang Um, and he wrote a book laying out this
Speaker 1: argument in two thousand nine called Catching Fire, How Cooking
Speaker 1: Made is Human. Rang Um is also one of the
Speaker 1: authors of this paper about whether apes prefer cooked food.
Speaker 1: And I'm not going to go into all of the
Speaker 1: pros and cons the arguments for and against the cooking
Speaker 1: hypothe sis. I would just say that my personal evaluation
Speaker 1: at a at a cursory reading of it is that
Speaker 1: it looks like it's kind of in the middle zone.
Speaker 1: It's one of those arguments that seems to have a
Speaker 1: lot of interesting things going for it, but it also
Speaker 1: doesn't line up all that well with the best existing
Speaker 1: evidence about the timeline for the control of fire by
Speaker 1: human ancestors. So I don't know. I'd say it's, uh,
Speaker 1: it's interesting but far from conclusive. But regardless of what
Speaker 1: we think about the the evolutionary effects of cooking on
Speaker 1: our direct ancestors, pointing out the theoretical background helps us
Speaker 1: see why the researchers performed the experiments described in this paper.
Speaker 1: So the authors of this paper begin raising a relevant question,
Speaker 1: which is that if you were to walk up to
Speaker 1: one of our ancestors roughly two million years ago, maybe
Speaker 1: to a member of the species Homo erectus, and you
Speaker 1: offered them cooked food, are we sure that they would
Speaker 1: like it or that they would prefer it to the
Speaker 1: same food in its uncooked state. You mean, like like
Speaker 1: a hot pocket. If you brought a hot pocket to
Speaker 1: one of our our ancestors, what would they make of it?
Speaker 1: And I feel quite certain that somebody who showed up
Speaker 1: with a hot pocket would be regarded as a worker
Speaker 1: of evil magic. But anyway, I mean, I think this
Speaker 1: is a worthwhile question to ask because we know that
Speaker 1: there are lots of types of food that we would
Speaker 1: probably rather eat cooked than raw. Maybe lots of you know,
Speaker 1: in this very person to person, but probably most people
Speaker 1: would rather eat grain, tough vegetables, most meats, and so
Speaker 1: forth in their cooked state. But it's possible that's just
Speaker 1: a cultural preference. So you know, we like cooked food
Speaker 1: maybe because we're used to it. Is there any way
Speaker 1: to test this out? And the authors here say, well,
Speaker 1: obviously not with archaic common ins, but an interesting analog
Speaker 1: would be to offer both cooked and raw versions of
Speaker 1: the same food to great apes, our closest living relatives,
Speaker 1: and see what their preferences are. So that's what this
Speaker 1: study looked into. So experiment number one, they were like, hey,
Speaker 1: let's try some tubers. Let's let's get together some care
Speaker 1: it's some sweet potatoes and some white potatoes and offer
Speaker 1: them to chimpanzees in a choice task that exposes them
Speaker 1: to both and then allows them to pick between the
Speaker 1: cooked and raw forms. And they found in the case
Speaker 1: of carrots and sweet potatoes, the chimpanzees definitely liked the
Speaker 1: cooked version better. On the other hand, it was interesting
Speaker 1: the white potato was more of a toss up. The
Speaker 1: authors noted that many chimps seemed kind of hesitant to
Speaker 1: take the initial samples of both cooked and raw white potatoes,
Speaker 1: and it was it was basically there was no difference
Speaker 1: in their preference between the two, which seems surprising to
Speaker 1: me because like, I love raw carrots. The cooked carrots
Speaker 1: are good too, but I cannot imagine wanting to eat
Speaker 1: a raw potato now. But the author said, well, maybe
Speaker 1: the chimpanzees are just kind of iffy on on potatoes
Speaker 1: in general. Okay, well that would make sense. Now. A
Speaker 1: second experiment they did had trouble really getting much of
Speaker 1: an answer. But what they looked into was to the
Speaker 1: extent that apes prefer cooked food overaw food. Why do
Speaker 1: they like it better? Is it the taste? Is it
Speaker 1: something about the texture. And so they experimented with a
Speaker 1: number of different grade apes they use chimp, spinobos, gorillas,
Speaker 1: and orangutans, and they offered them choices between carrots in
Speaker 1: the following format. So you could have whole pieces of
Speaker 1: carrot raw or cooked, grated carrot raw or cooked, and
Speaker 1: mashed carrot raw or cooked. And they found that when
Speaker 1: carrots were whole, apes definitely preferred the cooked pieces to
Speaker 1: the raw pieces. Again that they like cooked better, But
Speaker 1: after that things got more complicated. Apes generally did not
Speaker 1: seem to like the grated carrot in any format, and
Speaker 1: they preferred cooked whole carrots to raw, grated or cooked grated.
Speaker 1: Preferences were less clear in the mashed condition, though. They
Speaker 1: explained that some difference in results between the animal test
Speaker 1: groups for this experiment could have been influenced by neophobia,
Speaker 1: meaning fear of food in unfamiliar forms of course. You
Speaker 1: know that's common among humans also, is that we typically
Speaker 1: we like food. It's that we're familiar with and we're
Speaker 1: a little uh sometimes we're a little hesitant about foods
Speaker 1: that are unfamiliar. Yeah, like, for instance, the mashed carrot.
Speaker 1: How did it get mashed? But you know, if you
Speaker 1: were to encounter a mashed carrot in the wild, um,
Speaker 1: you know, they're the possibilities are not all that appetizing. Yeah, Okay.
Speaker 1: Experiment three or four, uh, and this one the author
Speaker 1: is right quote. This experiment provided great apes with choices
Speaker 1: between raw and cooked meat and raw and cooked apple
Speaker 1: malice domestica. We controlled for neophobia in this experiment because
Speaker 1: one of these items was familiar in its raw form
Speaker 1: apple and the other was familiar in its cooked form meat. Thus,
Speaker 1: this juxtaposed preference is determined by taste, slash, texture, and
Speaker 1: those which would be determined by familiarity with the test items.
Speaker 1: And in this test, the apes definitely preferred cooked beef
Speaker 1: over raw beef, but they did not show a significant
Speaker 1: preference one way or the other about the apple. Um. Again,
Speaker 1: it's funny thinking about how much this does or does
Speaker 1: not overlap with with our own preferences, though again, you
Speaker 1: know human preferences you always have to wonder about being
Speaker 1: a product of cultural familiarity. But they say the shows
Speaker 1: that neophobia is not the only factor affecting preferences because
Speaker 1: the apes were previously familiar only with raw apple, not cooked,
Speaker 1: and in this experiment, while they did not prefer the
Speaker 1: cooked apple, they basically showed no difference in preference between
Speaker 1: the two. Now, I mean, in all of this, we
Speaker 1: have the saying about comparing apples and oranges, in here
Speaker 1: we're comparing apples and meat. Uh So, I don't know,
Speaker 1: it feels I mean not that there's really a way
Speaker 1: to improve on this. I'm not. I don't mean to
Speaker 1: criticize the study, but it's like they're there are certain
Speaker 1: limitations in place with some of these comparisons. I feel,
Speaker 1: what do you mean that in that they're they're documenting
Speaker 1: different preferences by types of food like well, like, for
Speaker 1: for instance, to say, well we control for neophobia because
Speaker 1: the raw form apple will still looks like an apple,
Speaker 1: and the and the cooked meat still looks like the meat. Um,
Speaker 1: I don't know. I find that kind of a confusing rationale.
Speaker 1: Oh no, no, I think you're misunderstanding what they were doing.
Speaker 1: That they the neophobia thing was that they were familiar
Speaker 1: with cooked meat and with raw apple, but not with
Speaker 1: cooked apple or raw meat. And so they were trying
Speaker 1: to see, um, does this make any like does it
Speaker 1: just conform to in both cases? Do they prefer whatever
Speaker 1: they're previously familiar with. In the case of meat, they did.
Speaker 1: In the case of apple not so much. But they
Speaker 1: did another test. Uh. The fourth experiment was a test
Speaker 1: for novelty. Uh. They said, quote, we tested chimpanzees that
Speaker 1: were not given meat as a regular part of their
Speaker 1: diet and as far as was known, had never eaten
Speaker 1: cooked meat. And so they're offered raw and cooked beef,
Speaker 1: and again they definitely preferred the cooked beef better than
Speaker 1: the raw. So in the final discussion they say, yeah,
Speaker 1: on average, and the foods they tested here apes liked
Speaker 1: cooked food better than raw food. With some exceptions, they
Speaker 1: definitely prefer cooked beef, carrots, and sweet potatoes. They don't
Speaker 1: seem to have much of a preference on average between
Speaker 1: the cooked and raw forms of apple and white potato.
Speaker 1: And it seems like in general just didn't really love
Speaker 1: white potato. Uh. And then so they said neophobia might
Speaker 1: be a contributing factor to some of these results, but
Speaker 1: in experiments that tried to control for it, the ape
Speaker 1: still on average thought we're pretty cool with the cooked
Speaker 1: versions of food. But finally that this experiment had difficulty
Speaker 1: determining which characteristics of cooked foods the apes were responding to,
Speaker 1: you know, was it taste, was a texture, and so forth.
Speaker 1: And I do think that's an interesting question, like if
Speaker 1: if animals other than humans also prefer cooked food in
Speaker 1: most cases, why is it, like does it taste better
Speaker 1: to them? Is it like because it's softer to chew?
Speaker 1: I don't know. Maybe maybe we can come back to that.
Speaker 1: But anyway, the authors, you know, I mean it's difficult
Speaker 1: too because we have to stop and realize, like when
Speaker 1: they're talking about the difference between a cooked and a
Speaker 1: raw white potato, the cooked white potato in this experiment
Speaker 1: is also not buttered and salted and you know, and
Speaker 1: and prepared in these other ways. Like we're just stripping
Speaker 1: it down to um, to the basics of what cooking
Speaker 1: does to uh, this particular substance. Um. So, yeah, like
Speaker 1: if I were, you know, trying to set aside as
Speaker 1: much a you know human complexity as possible. If I
Speaker 1: were presented with just a plain white potato and a
Speaker 1: raw potato, I mean, I'd like to think I would
Speaker 1: still prefer the piked potato to the to the raw potato,
Speaker 1: but without anything added to it, it's still not a
Speaker 1: very attractive offer. Like the potato is is something that
Speaker 1: is best um consumed when there are other things done
Speaker 1: to it, other seasonings, other styles of preparation, etcetera. The
Speaker 1: human mind cannot comprehend the depths of blindness of a
Speaker 1: of an unseasoned potato. Yeah, the carrot is really the
Speaker 1: one that that throws me the most, you know, like
Speaker 1: because it part of me would guess that there's nothing
Speaker 1: quite like the raw crispness of the right like the
Speaker 1: carrot is crisp, we identify that with with freshness. The
Speaker 1: carrot is sweet. Um, Like what is changed in cooking
Speaker 1: the carrot that that that would that would make it
Speaker 1: more preferable, Like is it just it's just softer? Is
Speaker 1: it therefore seem riper in that sense? And then how
Speaker 1: does that affect the sweetness of it? With the sweetness
Speaker 1: be in any way enhanced by the cooking, I think
Speaker 1: in general, I can't speak to carrots in particular, but
Speaker 1: the authors actually address this. They say, um so, they
Speaker 1: talk about hypothesizing reasons that non human animals would prefer
Speaker 1: cooked food overall food, and uh so, one of the
Speaker 1: avenues they talk about is that cooking tends to cause
Speaker 1: chemical changes that increase the availability of flavor compounds that
Speaker 1: animals of all kinds seem to like. And so that
Speaker 1: the two main examples they offer are available sugars and
Speaker 1: available glutamates. Now sugars, that's I'm pretty clear to understand,
Speaker 1: and we can know that from experience. I don't know
Speaker 1: about carrots. It probab conforms to this and carrots, But
Speaker 1: I think about like onions, like eating a raw onion
Speaker 1: versus eating a cooked onion. The cooked onion is so
Speaker 1: much sweeter, like the you know, the amount of sugar
Speaker 1: you can taste in it is, I don't know, it
Speaker 1: feels like it's exponential above a raw onion. And yeah,
Speaker 1: and that's that's the case to where by cooking the
Speaker 1: onion you're kind of blunting it's um it's effects like
Speaker 1: the chemical weaponry if the onion is diluted. Yeah, the
Speaker 1: sulfur compounds and stuff, so so that's sugars. Apparently lots
Speaker 1: of foods have more available sugars when you cook them,
Speaker 1: so they taste sweeter. Tons of different animals can differentiate
Speaker 1: the levels of sugar and a food they're eating, and
Speaker 1: obviously prefer the thing that tastes like it's got more
Speaker 1: sugar in it because it is probably going to be
Speaker 1: more nutritionally dense, it has more calories per amount of
Speaker 1: the same amount of food. Uh. The other thing is
Speaker 1: the available glutamates. Glutamates are uh you know, does that
Speaker 1: ring a bell? Maybe it's in the phrase monose sodium
Speaker 1: glutamate MSG flavor, the umami flavor. Glutamates are are largely
Speaker 1: responsible for savory flavors that we associate with meat and
Speaker 1: and uh and also things like tomatoes and hard cheeses
Speaker 1: like parmesan and soy sauce and those those glutamates or
Speaker 1: that delicious savory umami feeling. And that's not just for
Speaker 1: humans either. It turns out tons of animals, I think
Speaker 1: even some invertebrates can detect umami flavor through the presence
Speaker 1: of free glutamates, which are increased by cooking. And while
Speaker 1: I was reading about this, I did get really amused
Speaker 1: by the idea of like inverted. I don't know which
Speaker 1: invertebrates exactly, but like do with lobsters really love soy sauce,
Speaker 1: would like there'll be centipedes who are going nuts for
Speaker 1: parmesan cheese. Thank anyway, Okay, So cooking often increases the
Speaker 1: availability of sugars and glutamates. So that's a flavor increasing
Speaker 1: flavors that broadly lots of an almost seem to like.
Speaker 1: And cooking tends to change the texture of food, usually
Speaker 1: by making it softer and easier to chew, and of
Speaker 1: course that appeals to the natural laziness present in all
Speaker 1: kinds of animals, not just us. So I think you
Speaker 1: could possibly argue that in a way, cooking, by massively
Speaker 1: increasing the presence of taste and texture qualities that our
Speaker 1: bodies and brains are already naturally on the look for,
Speaker 1: cooking could be viewed as a sort of ancient form
Speaker 1: of supernormal stimuli, like evolution shaped animal appetites to seek
Speaker 1: out nutritionally dense things like sugar and glutamates, which we
Speaker 1: detect by taste. Cooking causes chemical reactions that make more
Speaker 1: of those molecules available. Cooking softens food, appealing to our
Speaker 1: natural laziness. We don't like to spend an hour chewing
Speaker 1: on some tough bit of something to get it down.
Speaker 1: Tender food is better than tough food. So it's kind
Speaker 1: of like it's it's taking all these things we naturally
Speaker 1: seek out in foods we would find find in our environment,
Speaker 1: but making them way were dependably present in all kinds
Speaker 1: of foods. But anyway, the the authors of this study
Speaker 1: I was talking about, they say that their their findings
Speaker 1: conformed other bits of pre existing evidence that many other
Speaker 1: non human animals on average prefer cooked food overaw food.
Speaker 1: For instance, they cite a book by Brewer in nineteen
Speaker 1: seventy eight alleging observations that chimpanzees in the wild would
Speaker 1: prefer to eat seeds that have been naturally cooked or
Speaker 1: at least heated by wildfires. This was in a book
Speaker 1: by Brewer called The Chimpanzees of Mount Assyrik And uh, well,
Speaker 1: I thought that was interesting. Yeah, yeah, like that it's
Speaker 1: kind of primordial cooking right there. And they cite findings
Speaker 1: of of preferences in other mammals for example, Bradshaw at
Speaker 1: All in two thousand found that once cats have been
Speaker 1: exposed to both raw and cooked meat, they tend to
Speaker 1: prefer the cooked version. And they point to Ramirez in
Speaker 1: which found that rats ford cooked starch overaw starch. But
Speaker 1: I was looking at another study that actually asked a
Speaker 1: complementary question. So if the first question is do great
Speaker 1: apes such as chimpanzees prefer cooked food overaw food, it
Speaker 1: seems in in the majority of cases they do. Um
Speaker 1: the second question is do they in fact possess the
Speaker 1: ability to understand the cooking process? Would they, in theory
Speaker 1: at least be able to cook for themselves? And the
Speaker 1: study that looked into this was by Felix Varnicin and
Speaker 1: Alexandra g Rosati published in Proceedings of the Royal Society
Speaker 1: b Biological Sciences, called cognitive capacities for cooking in chimpanzees
Speaker 1: and this was and so the author's right here quote.
Speaker 1: The transition to a cook to diet represents an important
Speaker 1: shift in human ecology and evolution. Cooking requires a set
Speaker 1: of sophisticated cognitive abilities, including causal reasoning, self control, and
Speaker 1: anticipatory planning. Do humans uniquely possessed the cognitive capacity is
Speaker 1: needed to cook food. And oh man, when I when
Speaker 1: I was reading that line about about cooking requiring self
Speaker 1: control and anticipatory planning, I I felt a little bit
Speaker 1: cheapish because it immediately made me think about the problem
Speaker 1: of Uh Rob, I don't know if you do you
Speaker 1: do this too, but you're like cooking something and you
Speaker 1: just kind of keep snacking on it. Yeah, I mean
Speaker 1: you encountered that definitely with your more complicated recipes where um,
Speaker 1: I don't know, say you've h like a shepherd's pie
Speaker 1: comes to mind. I've recently made a vegetarian shepherd's pie
Speaker 1: for the weekend St. Patty's Day, And uh, yeah, once
Speaker 1: you've made like one part of it, like maybe you've
Speaker 1: made the um, the mashed potatoes, or you've made the
Speaker 1: you know, the the the meat and vegetable filling, Uh,
Speaker 1: you might be tempted, especially if you're a little bit hungry,
Speaker 1: you might be tempted to do taste and keep tasting
Speaker 1: those portions before everything comes together. Is one. Uh However,
Speaker 1: we tend if we're making shepherd's pie, were usually not
Speaker 1: tempted to eat the raw potatoes or right or or
Speaker 1: something like that before we begin cooking. But yeah, you know,
Speaker 1: like you've you've gone past the point where you're testing
Speaker 1: it for seasoning or whatever. Is just like okay, yeah,
Speaker 1: maybe have a little another bite of this, right, We
Speaker 1: were like, we're not gonna go hog wild eating a
Speaker 1: munch of just raw flour right out of the bag.
Speaker 1: But of course once the cookie dough is prepared, that
Speaker 1: is where the temptation may set it. Well, it turns
Speaker 1: out some chimpanzees have the same problem, but they do
Speaker 1: better at these kinds of anticipation and delay of gratification
Speaker 1: tasks then you might expect. So this study addressed these
Speaker 1: questions by performing some experiments with our closest living relatives,
Speaker 1: chimpanzees uh. The author has conducted a total of nine
Speaker 1: studies on chimpanzees living in a nature sanctuary in the
Speaker 1: Democratic Republic of Congo with the following results. They found.
Speaker 1: First of all, they replicated the finding that chimpanzees in
Speaker 1: general prefer cooked foods over the same foods in their
Speaker 1: raw form. Second finding is that chimpanzees in some way
Speaker 1: do under stand that food is changed by the cooking process.
Speaker 1: They can tell the difference and Uh, they understand something
Speaker 1: is happening when a raw food is exchanged for a
Speaker 1: cooked food. Third, they will delay gratification in order to
Speaker 1: upgrade a raw piece of food to a cooked version
Speaker 1: of that same food. Fourth, they will give up possession
Speaker 1: of a raw piece of food already in hand in
Speaker 1: order to transform it into a cooked food. And then fifth,
Speaker 1: they will transport or store raw food in anticipation of
Speaker 1: later opportunities to exchange it for its cooked form. And
Speaker 1: an interesting note on the method. I was like, wait
Speaker 1: a minute, are they going to be giving apes like
Speaker 1: an oven or something. They did not do that, actually, uh,
Speaker 1: because of course they didn't want to run the risk
Speaker 1: of the animals burning or otherwise injuring themselves. Instead, they
Speaker 1: used a plastic box with a false bottom that would
Speaker 1: exchange a piece of raw food for a piece of
Speaker 1: cooked food when shaken. Okay, I mean there are some
Speaker 1: limitations there obviously, but that that's essentially what an oven does.
Speaker 1: I guess, right, Well, obviously this is not the exact
Speaker 1: same thing as the cooking process, but they're trying to
Speaker 1: figure out, well, the chimpanzees at least figure out that
Speaker 1: there is a process they can put raw food through
Speaker 1: and get cooked food out, and will they delay gratification
Speaker 1: to go through that process? And the answer is broadly yes.
Speaker 1: The authors of the study right quote Together, our results
Speaker 1: indicate that several of the fundamental psychological abilities necessary to
Speaker 1: engage in cooking may have been shared with the last
Speaker 1: common ancestor of apes and humans, predating the control of fire.
Speaker 1: Uh and uh. I was reading a write up of
Speaker 1: this article in The Guardian by Hannah Devlin that had
Speaker 1: some good supplemental details. Uh. One thing I wanted to
Speaker 1: read this paragraph definitely made me say all buddy out loud.
Speaker 1: It was quote the chimps continue to opt for the
Speaker 1: cooked option sixt of the time when they had to
Speaker 1: carry the food some distance in order to place it
Speaker 1: in the quote oven, although since they often carried it
Speaker 1: in their mouth, this was a challenge and they sometimes
Speaker 1: appeared to eat the food on the way quote almost
Speaker 1: by accident. I sympathize with that, you know, the best
Speaker 1: of intentions. You know sometimes that that sweet tapos in
Speaker 1: your mouth and you're just going to start you in. Uh.
Speaker 1: The other thing was that, in terms of hoarding raw
Speaker 1: ingredients in the hopes that they could later be exchanged
Speaker 1: for cooked foods. Chimps in some cases hoarded up to
Speaker 1: twenty eight slices of sweet potato. Uh and Varnakin said
Speaker 1: to The Guardian, quote delayed ratification is a problem for
Speaker 1: us as well. We also have a tendency to nibble
Speaker 1: at food before we finished cooking. So that's exactly what
Speaker 1: we were talking about. And they don't even have excuses
Speaker 1: for it, like, you know, they can't rationally use the
Speaker 1: rationale well, i'm I'm I need to taste it to
Speaker 1: make sure that the flavor profiles appropriate, the need to
Speaker 1: make sure I don't need to add more salt or pepper, right.
Speaker 1: But while I think this is interesting and it's informative
Speaker 1: to the question of when humans first started cooking their
Speaker 1: food and what effects that may have had on on
Speaker 1: our ancestors one to two million years ago. Of course,
Speaker 1: the fact remains that there are no widely observed natural
Speaker 1: instances of animals in their natural habitat cooking foods by
Speaker 1: applying heat. But as we said earlier, heating is not
Speaker 1: the only form of cooking. Humans do all kinds of
Speaker 1: things to food that fall under the umbrella of cooking
Speaker 1: or cuisine that are unrelated to heat. So we take
Speaker 1: raw or cooked food items and we wash them, or
Speaker 1: we age them, or we ferment them, and we season them,
Speaker 1: we butcher them in certain ways, we skewer them or
Speaker 1: cut them up in special ways, we combine them together
Speaker 1: in interesting ways. And it's frankly surprising how many of
Speaker 1: these culinary manipulations and modifications that humans do are mirrored
Speaker 1: at some level throughout the animal world. And so I
Speaker 1: thought that's what we could explore for the remainder of
Speaker 1: this series, all the different ways that animals cook. And
Speaker 1: you had some really interesting examples. I think that had
Speaker 1: to do with maybe what could broadly be called some
Speaker 1: form of butchering or skewering of food as a preparation method. Yeah. Yeah,
Speaker 1: I have a couple of good examples here, um and uh.
Speaker 1: And one of them I think is a pretty pretty
Speaker 1: obvious one. Let's start with an amusing one, but perhaps
Speaker 1: the less involved one, and that is the case of
Speaker 1: the lamber guy or or bearded fulture. So these birds
Speaker 1: are found in parts of Africa and Eurasia, and these
Speaker 1: birds are known for their amazing ability to eat and
Speaker 1: digest bones, and I think that's that's one of the reasons.
Speaker 1: This is a great example bird to start with, because
Speaker 1: it already has robust um anatomical features and internal abilities
Speaker 1: when it comes to the processing of of what is
Speaker 1: you know, arguably a very difficult food. They're they're eating bones,
Speaker 1: but they have you know, they have these wonderful bites.
Speaker 1: They can bite through brittle bones, they can swallow large
Speaker 1: chunks of bones, and their digestive system can handle it. Um.
Speaker 1: And yet there are still going to be challenges that
Speaker 1: are too great for them to handle without a little
Speaker 1: ingenuity um and uh. And so basically they have a
Speaker 1: butchering challenge ahead of them. You know. Butchering is what
Speaker 1: we do when we we have a carcass and we
Speaker 1: don't just want to eat from the carcass. We can't
Speaker 1: cook the whole carcass. We have to take things apart,
Speaker 1: remove things that are inedible or are not desired or
Speaker 1: used for at another time or for another purpose, you know,
Speaker 1: all the various reasons you have to take a part
Speaker 1: of a carcass. Um. Yeah. And in fact, external processing
Speaker 1: of animal carcasses is hypoth It's not known for sure,
Speaker 1: but it is hypothesized to be one of the earliest
Speaker 1: drivers of tool use in humans. That why would a
Speaker 1: humans start using a flat rock as a cutting surface,
Speaker 1: maybe to get meat and tough hide parts and stuff
Speaker 1: off of an animal kill. Yeah. Yeah, that we've talked
Speaker 1: about that on the show in the past when when
Speaker 1: talking about early tool use and evidence of how those
Speaker 1: tools are being used. You know, we can look for
Speaker 1: those signs um on the bones of them having been scraped.
Speaker 1: In some cases, it's also evidence of cannibalism taking place
Speaker 1: um in a given people versus uh, you know, I'm
Speaker 1: just merror um you know, murder or warfare because of
Speaker 1: the signs of tool use on the brains. Yeah. So
Speaker 1: uh yeah, this is a case where the lamber guy
Speaker 1: are is gonna occasionally find some chunks of bone that
Speaker 1: are too big to handle. They need to butcher it,
Speaker 1: they need to take it apart. Uh but what what
Speaker 1: tools are available to them? Well, luckily they can. They
Speaker 1: can pick up a pretty big bone. I think, I
Speaker 1: think they can basically take off with something equal to
Speaker 1: their own weight. Um. So they've developed the practice of
Speaker 1: taking larger bones up high into the air and then
Speaker 1: dropping them onto rocks in order to break them open
Speaker 1: or shatter them. Sometimes it takes more than one try,
Speaker 1: and it's a it's also a learned tactic, so generally
Speaker 1: it takes around seven years for one of these birds
Speaker 1: to to master it. And you'll find examples of immature birds, uh,
Speaker 1: just dropping bones incorrectly, like they haven't really figured out
Speaker 1: exactly where you're supposed to drop them or or when
Speaker 1: you release them. But they'll get there. They'll eventually learn it,
Speaker 1: and it will open up new possibilities to them in
Speaker 1: terms of what they can eat. Oh that's my second
Speaker 1: al buddy of the episodes, imagining the vultures dropping the
Speaker 1: bones wrong, Like, yeah, nice job, Ted. Now they sometimes
Speaker 1: um prey on I'm live creatures as well. It's not
Speaker 1: just bones. And probably one of the more um alarming
Speaker 1: and interesting examples is that of the tortoise. They may
Speaker 1: fly up with a tortoise that again has to be
Speaker 1: a tortoise they can physically carry up, but then they
Speaker 1: can drop that as well, treat it like an oversized bone,
Speaker 1: an attempt to bust through those bony defenses. And uh,
Speaker 1: this may ring a bell for for some of you
Speaker 1: out there, because this is of course how the Greek
Speaker 1: father of tragedy, Escalus, was said to have died in
Speaker 1: four see uh this according to the two accounts by M.
Speaker 1: Valerius Maximus and our old friend Plenty of the Elder. Now,
Speaker 1: this may well just be a story. We have to
Speaker 1: drive him, but it basically goes like this. Yeah, Escalus
Speaker 1: goes to an oracle. He receives a prophecy that he
Speaker 1: will he will one day be killed by a falling object.
Speaker 1: So he's a smart guy. He says, well, nothing can
Speaker 1: fall on me if I'm outdoors. So he spends more
Speaker 1: and more time outdoors because, yeah, there's nothing's going to
Speaker 1: fall from the roof. There, no shelves. Sounds like a
Speaker 1: pretty safe that. Yeah, that makes sense. It's like, if
Speaker 1: there's an earthquake, where do you want to be get
Speaker 1: away from Buildings're gonna be out in the middle of
Speaker 1: a field, right. Unfortunately he is in the territory of
Speaker 1: the lamber guy or it's thought that this may may
Speaker 1: be referring to Lamber guyers Um. Suddenly a great bird
Speaker 1: flies over head. That great bird has a tortoise in
Speaker 1: its clutches, and it mistakes escalus head for a hard
Speaker 1: rock um. A lot of times he's depicted as being,
Speaker 1: you know, bald on top, and so the bird drops
Speaker 1: the tortoise on him, killing him instantly. Um. Again, possibly
Speaker 1: just a misunderstanding or an entertaining tale. Um. But you'll
Speaker 1: find various accounts of deaths like this from the ancient
Speaker 1: world where you have to stop and ask, did they
Speaker 1: really die like this or is this just a nice story?
Speaker 1: This is the story that developed about their death. If true,
Speaker 1: he died by accidentally running a foul of an avian
Speaker 1: butchery processes. Some I'm seeing vague connections to the Texas
Speaker 1: chainsaw masker. But now when it comes to a van butchery.
Speaker 1: The best example, of course is the shrike. Now, if
Speaker 1: you've never seen a shrike, let's look up pictures of them.
Speaker 1: But they're they're generally, I mean, for me, they're an
Speaker 1: unimpressive looking bird. Uh. This is gonna be different for you,
Speaker 1: depending on how into birds you are and if you're
Speaker 1: or a birdwatcher, etcetera. But you know, they when you
Speaker 1: when you compare what they look like with what they do, Uh,
Speaker 1: they don't look quite as impressive in my opinion, because
Speaker 1: what they do is very impressive. Uh. They're thirty four
Speaker 1: species of shrike in four genera in the family lanta day.
Speaker 1: And if you're yeah, if you're not a bird enthusiast
Speaker 1: or a bird watcher, uh, you might just look at
Speaker 1: a shrike and say, well, that looks like a bird,
Speaker 1: But it's not what they look like. It's what they do.
Speaker 1: And basically what they do is they engage in kind
Speaker 1: of a complex butchery situation. That's why we call them
Speaker 1: butcher birds. Lanta day is derived from the Latin uh lantus,
Speaker 1: which means butcher. So they don't wear little aprons or
Speaker 1: you know, wrap morsels of meat and white butcher's paper.
Speaker 1: But what they do is they take insects and even
Speaker 1: small vertebrates that they kill and they impale them onto
Speaker 1: thorns like little lad draculas. Wow. And by the way,
Speaker 1: their methods, you know, it's one thing to get the is,
Speaker 1: you know, various bugs and insects, but their method of
Speaker 1: killing small rodents is actually quite brutal. Is pointed out
Speaker 1: by Hannah Waters in a two eighteen article for the
Speaker 1: Audubon Society. Quote, they grasp mice by the neck with
Speaker 1: their pointed beak pinched the spinal cord to induce paralysis,
Speaker 1: and then vigorously shake their prey with enough force to
Speaker 1: break its neck. Oh, that's interesting because it's like a
Speaker 1: bird version of a common predatory tactic I think used
Speaker 1: about like some big cats. Right. We talked about this
Speaker 1: with Mary Roach in her book, talking about various kinds
Speaker 1: of big predatory cats that will attend to bite along
Speaker 1: the back of the neck, which is how their characteristic
Speaker 1: attacks are identified in humans. Yeah. I have noticed this
Speaker 1: when I watched all the Jurassic Park movies with my
Speaker 1: son a year or so ago. Well, I forget which
Speaker 1: one it was in, but there's one in particular where
Speaker 1: you see the dinosaurs, the raptors in particular, UM, killing
Speaker 1: by by clamping onto the back of the neck, which
Speaker 1: I thought was a nice touch. So anyway, but no
Speaker 1: it was. No. I but I've got a question. Okay,
Speaker 1: so this seems gratuitous. The bird just takes its prey,
Speaker 1: which normal bird would would just capture and then kill
Speaker 1: and then eat. But this bird impales it on a
Speaker 1: thorn on a plant. Why do we have any idea
Speaker 1: like what the purpose of this is? Uh? Yeah, and
Speaker 1: there seemed to be three different reasons, um, and I
Speaker 1: do have to acknowledge that, yes, this is exactly what
Speaker 1: you mentioned Texas chainsal Masca earlier. This is exactly what
Speaker 1: happens in one of the kills in tcm Uh. He
Speaker 1: cracks a victim on the head, uh, you know, and
Speaker 1: take takes her out, but then he sticks her onto
Speaker 1: a meat hook. Uh. And that's that's basically what the
Speaker 1: shrike is doing. So there are three different reasons to
Speaker 1: do this that that researchers have identified. One and this
Speaker 1: is pretty neat and this is this is is that
Speaker 1: it's about tearing the meat once and let's say an
Speaker 1: insect is impaled on that thorn. You can then pull
Speaker 1: on the creature's body and you can rip it, cut
Speaker 1: it into smaller pieces. So it's leverage. It allows you
Speaker 1: to get better leverage on the for butchering the insect body. Right.
Speaker 1: It's it's not something we really do because we you know,
Speaker 1: we can use farm you know, all these other tools.
Speaker 1: But imagine if you didn't have tools, if the thorn
Speaker 1: was the only tool. Um, because that's particularly i mean,
Speaker 1: that's exactly the situation that the bird is in. The
Speaker 1: next reasons for the shrike to put something on the
Speaker 1: on the on the thorn is just as a means
Speaker 1: of storing the meat. Uneaten portions of the meat can
Speaker 1: be left on the thorns and the bird can return
Speaker 1: later to eat some more m okay, as opposed to
Speaker 1: like storing it on the ground where something else is
Speaker 1: more likely to come along and take it. Right. And
Speaker 1: then finally, this is I think probably the most interesting
Speaker 1: of the three and one that um I wasn't really
Speaker 1: familiar with that I was. I knew about shrikes and
Speaker 1: about the category one and two here. But the third
Speaker 1: reason is to potentially detoxify the meat um. And this
Speaker 1: is where we get more specific with this with some
Speaker 1: of the prey species that are targeted. Uh. It's a
Speaker 1: way of processing the meat of a toxic prey animal
Speaker 1: UM so that the bird can then eat it. So
Speaker 1: the bird will leave a body on the spike for
Speaker 1: like a period of one to two days, allowing the
Speaker 1: toxins in the body to degrade to the point where
Speaker 1: it can be safely eaten. Okay. So this might be
Speaker 1: the case in like an insect that has a poison
Speaker 1: within its body that has a fairly short chemical half life,
Speaker 1: and it's if it's not replenished by the live animals body,
Speaker 1: it's going to eventually degrade over time exactly. Yeah, and
Speaker 1: some for some specific examples. The loggerhead shrike does this
Speaker 1: with luber grasshoppers as well as with the species of
Speaker 1: beetle and moth, and great gray shrikes have been observed
Speaker 1: to do this with black cone headed grasshoppers. So so, yeah,
Speaker 1: the shrike is is fascinating, not only because there's something
Speaker 1: kind of grizzly and wonderful about what it does. Uh.
Speaker 1: But yeah, by doing these three things with its practice, Uh,
Speaker 1: it's engaging in a in in several different things that
Speaker 1: that we do with our with our cooking process, you know,
Speaker 1: the butchery of the meat, the butcher or they just
Speaker 1: the the taking a part of a given element, uh,
Speaker 1: the storing of that element and then detoxifying that element. Now,
Speaker 1: we tend to we do this in a number of
Speaker 1: different ways. It may be cooking something and the cooking process,
Speaker 1: the heating process itself destroys the toxins. It also maybe
Speaker 1: and we've touched on this before in our Dangerous Food series,
Speaker 1: it may also be about removing parts of the body
Speaker 1: or parts of the plant that would otherwise be toxic
Speaker 1: to us. Uh. But but we have just specific cases
Speaker 1: of the of the shrike carrying this out just by
Speaker 1: leaving it on the thorn long enough. Well, I'm impressed. Yes,
Speaker 1: they are impressive creatures. All right, Well, we need to
Speaker 1: wrap up part one here, but we're going to be
Speaker 1: back next time with more of the uh the quote
Speaker 1: cooking or otherwise, you know, meal prep cuisine behaviors of
Speaker 1: non human animals. Definitely want to talk about some interesting
Speaker 1: behaviors that have been called washing, but maybe more obscure
Speaker 1: in nature than that. Yeah, in some cases at least
Speaker 1: it's kind of mysterious. And we'll get into into all
Speaker 1: of that, plus plus other examples in the meantime. Certainly,
Speaker 1: right in, let us know what you think about what
Speaker 1: we discussed here today, especially if you have any direct
Speaker 1: experience with us. Have you observed the shrikes in the wild,
Speaker 1: have lambergeyers dropped tortoises at you? And you've you know,
Speaker 1: luckily been able to get a less rocky looking hat
Speaker 1: over your head just in time. Do you prefer raw
Speaker 1: potatoes to cook? Oh? Yeah, yeah, I mean he's going
Speaker 1: to have some insight on all of that, so yeah,
Speaker 1: right in, let us know, we'd love to hear from you.
Speaker 1: In the meantime, if you would like to check out
Speaker 1: other episodes of Stuff to Blow Your Mind. Core episodes
Speaker 1: published on two season Thursdays. On Monday we do a
Speaker 1: listener mail, on wind Day we do a short form
Speaker 1: monster fact or Artifact episode, and on Fridays we do
Speaker 1: Weird How Cinema. That's our time to satisfied most serious
Speaker 1: concerns and just talk about a strange film huge things.
Speaker 1: As always to our excellent audio producer Seth Nicholas Johnson.
Speaker 1: If you would like to get in touch with us
Speaker 1: with feedback on this episode or any other, to suggest
Speaker 1: topic for the future, or just to say hello, you
Speaker 1: can email us at contact at stuff to Blow your
Speaker 1: Mind dot com. Stuff to Blow Your Mind is production
Speaker 1: of I Heart Radio. For more podcasts for my heart Radio,
Speaker 1: visit the iHeart Radio app, Apple Podcasts, or wherever you're
Speaker 1: listening to your favorite shows.