2010 Paul D. Bartlett, Sr. Lecture - Catching Fire: How Cooking Made Us Human

[Applause] well thank you Lisa and thank you to the trustees of the Lindo Hall library and the Harvard Yale Princeton Radcliffe clubs for the tremendous privilege of being able to come here and share with you my passion um I find it slightly alarming giving a talk like this because uh it's very easy to get carried away with uh the interest that I've felt for the last 10 years in this question of what is it about cooking that is really important for understanding us uh both today and even more so in our evolutionary past for those of you who've been sitting here for the last five minutes looking at this picture I'm wondering what you're thinking about it uh what it purpose to show is chimpanzees making kebabs actually remarkably as I understand it only about three hours away from here there are great apes that do cook there are bonobos in the great ape trust at um in Iowa uh who have been brought up with humans and have done some um playing with barbecues and and cooking themselves but in the wild where this Photograph was taken I've got to disappoint you they do not cook this is a photoshopped photograph what they're actually doing is they are holding their wands those sticks into an ant nest and the ants are crawling up the sticks and then they hold up the sticks and wipe the ants off and you have a little golf ball size collection of ants and pop them into your mouth so they're very delicious and I've tried them a little bit um sour crunchy a hidden depths of flavor inside but not cooked you should be able to look at this picture I didn't test you maybe I should have done but you should have been able to look at it and say yep that was a fake because cooking is the signature feature of the human diet and what I want to do is to think about what it means because as the great gastronomist brilla savarang said in the 1820s you are what you eat and you'd think that that means you are what you cook you are something about cooking well it's odd about cooking it's odd about the control of fire because no other animal uses fire and we all need fire it's hidden from us very often right now we haven't probably seen fires most of us today but somewhere in a generator somewhere in a power station there is fire that is producing the energy that we are using right now we all know fire is important we all know cooking is important and Darwin knew that these things were important here's what he said man has discovered the art of making Fire by which hardened stringy Roots can be rendered digestible and poisonous roots or herbs innocuous this discovery of fire probably the greatest ever made by man accepting language dates from before the dawn of History the greatest ever made by man we can't know anything about language in the past because it's so difficult to get any information about it but you'd think we'd know something about fire by now and yet there's been almost nothing written about the impact of this greatest discovery why not here I think is one of the reasons he said a discovery made by man and this immediately sets you off thinking in a particular direction here's the conventional wisdom I missed a slide before I get to the conventional wisdom uh here is just a reminder in case you didn't know that uh the practice of cooking is indeed a human Universal there are constant little stories about people who survive entirely without cooking none of them are true they've never been true every time you investigate any of these cases it always turns out that the people do in fact cook their food everyone knows how to make fire everyone knows how to to cook and we all eat some food raw every society eats some food raw but hunters and gathers throughout the world they cook the signature feature of the human diet all right well with that in mind nevertheless fire has been regarded and the control of fire and cooking as relatively unimportant and here I think is the reason the conventional wisdom says that human evolution very well documented in the fossil record goes from here the president of Harvard back to the president of Yale and then to a species almost two million years ago that is so similar to us that they could walk into a store in Kansas City and buy clothes off the peg that is not true for the species that preceded them the australopithe scenes those still climbed about in trees and they had big tummies and they know basically much more like chimpanzees standing upright they were about the size of chimpanzees so something big happened here the conventional wisdom is they learned to eat raw meat and the eating of raw meat converted them into the human size and shape and from then on it was just a question of getting slightly bigger brained and since archeology suggested that fire did not come in until sometime like this then that meant that it didn't do much at all here's a closer look at the fire here is the pattern of human evolution as it's well known from the fossil record starting almost two million years ago from those chimpanzee-like australopitheses Homo erectus that thing that could walk into a store in Kansas City and get clothes off the peg living in Africa going off to Asia as well and then becoming another species the president of Yale and then neanderthals maybe that's Princeton and finally homo sapiens two hundred thousand years ago now the fire record is very good for the last two hundred thousand years including the Neanderthals and it's pretty darn good so you've got to be an enormous skeptic to reject evidence of the control of fire from half a million years ago and even this one that almost everybody will go to the bank for with um this is in Israel and very well documented in all sorts of ways evidence the control of fire now there are people who say yeah I've dug up these sites at ubedir or jessawanja and I can absolutely convince you that fire was controlled then but there are other people who say no I refuse to be believe it so basically you've got a dying record and the Skeptics have said well we can only be certain here so maybe fire only emerged very late my attitude is much more likely the archaeological record is simply decayed because the record of fire does Decay very quickly we know it decays very quickly you can go out and make a fire in the woods and three weeks later you won't find any trace of it so you've got to be very lucky to find traces of fire from early on I think we need to move away from the archeology and towards the biology now I particularly thought this when I used to spend more time than I currently do and I still sometimes do this studying chimpanzees by following them from dawn until dusk from the time they got out of their nest until the time they went to bed and I was studying feeding behavior when I first first started doing this in the 1970s and I tried to eat all the things I ate and so on the occasions when my alarm clock went off and I was too rushed to organize myself to take some proper decent human food with me I would spend the day relying on my knowledge of chimpanzee foods and eat what they eat which after all makes a lot of sense because if we indeed are adapted to eating raw food as is the standard Theory then we should be able to eat the kinds of foods the chimpanzees at they're our closest relative and this is an ideal habitat for chimpanzees in Western Tanzania well the foods are frankly not that great um this uh this female is chewing the stem of uh of a thing a little bit like a canthus that you've probably seen in your in the in the yards it's worked widely grown in the United States and it's very prickly and it tastes a bit like um oh I don't know jelly deals on a bad day here's a representative sample of the 15 20 foods that they eat in any one day and frankly they're not very nice and so I would get hungrier and hungrier as I tried sampling these things and you can't fill your belly with any of these foods and I would long for the cooked food in the evening now it took me being a Harvard Professor only about 25 years to figure out the significance of that and um I was put off by this it seemed to me that I was getting more energy out of a bowl of pasta than I was out of several pounds worth of raw fruits and leaves that the chimpanzees were eating cooking would have some impact on the energy I would get out of food so I went to the standard sources of information to find out from the nutritionists what happens when you cook food do you get more energy out of it well if you look at the food labeling system then all of the information there comes from the USDA National nutrient database and this supplies information to people around the world there's an equivalent thing in Britain where Labs submit their information that has been carefully tested and sometimes the labs have looked at both the same food raw and cooked and you can compare and I've done graphs showing the difference between raw and the cooked and you get the same astonishing result as you do with these sausages that is to say a raw sausage is said to be worth 690 calories per 100 grams of dried sausage and the cooked is worth slightly less so if we all want to get fat apparently we should go eat eat raw sausages now this is what is said in the official guide to a calorie value and it's wrong they get a c minus how do we know this it took me a long time to sort of slowly build up the data but the simple story is this Angela here spent through one phase of her life eating cooked food and another phase of her life eating raw food only and like many people who have done raw food diets raw foodists they post their photographs on the web to say look what a difference it makes because it's a great way to lose weight this suggests that if you eat cooked food you get more out of it somehow and the same can be said for many different animals here are some samples you will not see a dog that is living on wild food or a cat that's living on wild food looking like that normally you see a hedgehog that's looking on wild food you probably can't see everyone but that is a hedgehog here and and uh this actually was taken from the BBC uh News website a couple of weeks ago because what you've probably seen there's a bit of a fear in Britain that uh the Obesity crisis is spreading to hedgehogs too generally this has become the number four item on the BBC News website people are giving them cooked food and they're doing what we do they are getting too many calories now the amazing thing about this is that the raw foodists are not in Western Tanzania eating the wild Foods they have all sorts of advantages they are eating food that has been domesticated by our farmers and therefore converts something like I don't know the food in the wild I mean the fruits taste like a raw turnip or a crab apple on a bad day you know they don't taste like apples and oranges and bananas that have been domesticated um the food that the raw food is eating has been Blended it's been ground it's been dried up to 114 degrees Centigrade because many raw foodists are low heating up to a certain temperature they are including meat in their diet a lot of their food is is oil so that's very high calorie it's not seasonal because they're tapping into the global food resource this is food from all around the world so there's never a period of seasonal food shortage and they're not taking anything like as much activity as if you're a hunter and gatherer and you're going out schlepping kilograms of this food uh several kilometers back to Camp every day after you've been out digging in the hot sun and despite all those advantages they're losing weight so what's going on that was just a photograph I think it's worth showing some data on this point um here are data this is on the left body mass index the weight for height and you see the difference between people who eat their food cooked and the different dots refer to people who've been vegetarian for different lengths of time and people who eat their food Raw the blue are males and the red are females so what this shows is that those who eat cooked have a higher body mass index more weight for height than those who eat their food raw regardless of whether or not they are vegetarian even in some cases for 20 years or eat meat me eating meat contributes very little to the difference and we see the same among the raw foodists here you have a statistical analysis showing there's no effect of meat eating on the body mass index of raw foodists you see here the people eating 70 of their food raw down to 100 a lot of them are in this area because it's very difficult for people to have the strength of will to stick to a raw food diet you might say now how certain are we that it really is cooking as opposed to processing in other ways that is responsible for the difference in the quality of the food well we wanted to find out as I've been investigating this over the last decade I've been amazed at how difficult it is to get even the most basic information I found in the 1930 a reference in an editorial of the British medical journal called Lancet to studies of rats that had been done showing that rats got more energy out of cooked food than they did out of raw food but there was no reference to the studies I've combed the literature I can't find the studies we've had to do the studies again no one's ever done it this is cooking you know we all cook no one's ever investigated what cooking means well I'm developing a new Theory the theory that cooking gives you energy it hasn't been there before so in order to test this some students and I looked at what happens with mice and we developed a little uh a Renown which mice could be tested and we fed them all sweet potatoes sweet potatoes that have been prepared either raw whole sweet potatoes raw and pounded cooked and whole cooked and pounded and what we did was we gave adult mice six days of good nuggets nuggets the Kibbles that the lab child consists of and then four days on one of the sample diets and then six days back again and four days on a sample diet and so on and and mixed up the order in which these were given and then here's the results we find that when they are eating the raw whole sweet potato they lose weight rapidly and the same is true if they're eating it raw and pounded not quite as much so pounding helps a little bit but if it's cooked whether it's whole or pounded then they maintain their weight so mice apparently are not adapted to eating just sweet potatoes in the wild anyway now we're on the trace of what does cooking do now it's been known for years that if you um if you heat protein then it makes the protein more easily accessible to digestive enzymes but against that it's been assumed for years that however much you cook protein it doesn't matter because you will completely digest your RAW Protein why should you make this assumption well there are some reasons here why people would think that in the case of chicken egg protein it would be exceptionally high quality material it's been adapted to be well digested as it were by the chicks and uh and is known that it's very effective in terms of its ability to provide food for rats experimentally but that is when the when they're cooked but maybe the most important thing is that people like Arne Schwarzenegger they they swear by raw eggs they think it's really good for building muscle and in fact his his mentor Vince geronda he's the one who said you should eat 36 raw eggs a day that's the way to get muscle so you know experience apparently was telling okay well now there's another reason too which is that people did some studies in which they looked at the difference in the amount of whole protein that you eat and then the amount of whole protein that you excrete not very attractive studies but important from the point of view of digestibility and they found that you you digest it all but those studies are fundamentally flawed they're flawed because when you look at an organism like me you're actually looking at two kinds of things one is what you can see and then the other is what's going on in our bowels in our colons our large intestines where we have 500 or more species of bacteria that are competing with us in a sense for the food and any food that gets through the end of our small intestine and into our large intestine is available to be eaten by those bacteria and in the case of protein none of the protein that gets into the large intestine having escaped digestion through the small intestine none of it is only used to us it's only food for the bacteria so in order to be able to find out whether or not we can get much out of the protein what we've got to do is to look at people who have had an unfortunate operation in which they've lost their large intestine and their small intestine ends in a bag that is brought to the surface of the abdomen and every 15 minutes a researcher can come along and say oh can I please see what has passed through your small intestine without being digested and that is what people have done in one case for one protein cooked egg protein and it turns out that there is an enormous difference in the digestion of the protein according to whether it was cooked or raw so in these patients these ileostomy patients you find that if the protein is cooked 90 of it's digested by the time it ends the small intestine if it's raw only 50 percent an ingenious technique allowed them to compare with healthy patients so it's still early days but it looks as though it matters a lot whether or not you cook your protein and the reason is pretty easily guessed at it is because the protein is denatured by heat just as it is by acid meaning the strands open up and then the digestive enzymes can easily attack it let me give you one other example of how cooking might affect the amount of energy we get out of our food now this is a trick first of all because I'm not going to talk about cooking I'm going to talk about a consequence of cooking and that is that cooking makes everything softer and if you're digging your partner in the ribs because they made a piece of meat tougher then Okay cooking is meant to make every food softer that's what Mrs Beaton said it's the aim of the cook is to soften the food so here's an experiment Amazing Experiment that looks at softness and isolate softness as a variable it does so by taking the nuggets the Chow that laboratory rats are being fed and just changing them in one way making them softer it's like taking wheat and making puffed wheat they took the Nuggets they decomposed them and then they recomposed them at the original volume and then at twice the volume so the ones that are twice the volume the little nuggets have got exactly the same weight exactly the same number of calories because all they did was added air so they've got a puffed version and an unpuffed version and it was easier to crush the puffed version okay so did that make any difference well it didn't make any difference to how much they add this showed that they compared the rats on how much they ate and it was the same actually that slightly less of the puffed version what about body weight here's the body weight effect they grew them from weaning initially there's no difference and then by the time they're approaching adulthood there is a significant difference the ones who had been eating the soft diet were significantly heavier than the ones eating the hard diet even though they had eaten exactly the same amount they've taken in the same number of calories and by the way they'd expanded the same amount of energy in Locomotion because they were able to measure that so that's kind of mysterious except it's not mysterious because we know that there's a lot of energy that we expend when we digest a meal you digest a big meal you want to sit there in your chair sweating slightly rather than going for a swim every animal feels the same way and here you see it for these rats you see that after eating a meal then their metabolic rate shoots up and comes down again but look at this it shoots up more for the ones eating the hard diet than it one's eating the soft diet so this means that simply the physical state of the food affects the number of net calories you get out of it so that suggests that it's a contributor to the Obesity crisis because the number of calories that the nutrient database is measuring is exactly the same now for Wonder Bread as it would have been for a whole grain bread and it's exactly the same as it was a hundred years ago there's been no allowance made for the processing in the way that those measurements are taken the basic problem with the USDA is that the way they measure the number of calories in a raw sausage or any other kind of food is by blowing it up they put it in a thing called a bomb calorimeter where you put a spark through the food and then it explodes and then they measure the amount of heat given off so their assumption is that when we digest food we're blowing it up but guess what you know no spark goes off it's a different system and that's why it's important to look at the amount of work it takes to digest the food so this suggests that something more may be going on we had a look at this with meat we can't do it yet with humans but maybe we're going to find a way to do it we did it with Pythons we fed rats to pythons well we didn't feed rats we fed model rats we we rolled beef up into rat shapes and gave them to pythons and sometimes the beef was ground and sometimes it was cooked and sometimes it was ground and cooked and if it's ground then the pythons had an easier deal with the meal 12 reduction in the cost of digestion if it was cooked 12 reduction in the cost digestion and the effects were additive so if it's ground and cooked it was 23 this is why we like hamburgers we grind it and we cook it it's why hunters and gatherers around the world both cook it and not grind because they don't have Grinders but pounded when meat is so tender that the sinews will fall apart it's usually crushed in a mortar what we're seeing here is our lab and other people's efforts to try and find out what are the mechanisms by which cooking gives us energy it's perfectly clear from raw foodists that cooking gives us energy but we need to find out why and it'll surely help us guiding our own food choices so I didn't talk about gelatinization of starch I talked about denaturation of protein food softening gelatinization of collagen thinning of lipids reducing the water and reducing the pathogens all these things are going to contribute many of them additively to the calories we get out of food we don't know how much it affects us we're going to try and find out in the next five or ten years in our lab maybe other people will too would be great is it 25 my guess is it's going to be more than that 50 maybe 100 of the calories it's a lot so if you've got a relative that decides to go on a raw food diet and uses the caloric values produced by the USDA nutrient data website or any other site then after those people have starved to death it seems to me that you can justifiably sue the USDA so I think that the reason that a baboon is being cooked on this fire by hunters and gatherers Northern towns near is not what Levy Strauss said which was it's a psychological device to separate us conceptually from the animals I think it's because we get more calories out of it now calories really matter to wild animals here's an example for our chimpanzees but there are tons of examples like this from all sorts of wild animals this shows that a chimpanzee they get just a little bit more ripe fruit in its diet because it's dominant or because it lives in a better area or because it happens to be a better time of year does much better in terms of something that matters to Evolution the rate at which it reproduces five percent more ripe fruit in the diet four months quicker to conceive a baby so little bits of energy matter we're talking about big bits with the cooking think more about what's going on with humans here we have a chimpanzee like any other wild animal it lives on a raw food diet it makes new chimpanzees on a raw food diet what about humans there is only one set of data looking at the reproductive performance of women on a raw food diet and the answer is that by the time they're eating their diet 100 raw 50 of them are completely amenoriac this means they are not menstruating they are ovarian Cycles have closed down they cannot produce an egg they cannot have a baby and the same is true for another unknown percentage but maybe 25 percent because they are seriously sub fecund and remember this is despite the fact that they got all those advantages and they're the best possible conditions a human cannot live on raw food in the way that a chimpanzee can I think what this means is that there is no doubt that we are not like other animals people used to say animals eat their food raw humans are animals therefore humans can eat their food Raw well it's not true humans are different kind of animal we're an animal that's biologically adapted to eating cooked food and we know why we can see what's going on we have tiny little guts if we were good decent Apes we would all of us have guts that are sticking out a very long way like a gorilla after a long day but here we have the size of our guts the total volume of what goes into our our bellies um against body mass and we see it for primates as a whole and the point that falls furthest from the central curve for primates is humans we have the smallest guts of only primate we have the smallest teeth of any primate our guts are too small to carry the amount of food we would need to keep it in the belly for a long time to be able to process it well we cannot well process in our mouths the tough raw foods so I think that we have to recognize that humans are a different kind of species from Every Other Well biologically adapted to eating our Foods cooked whether we happen to be chewing a goanna like this mardu woman from Western Australia or eating boiled monkey heads well that's kind of a fascinating question but it doesn't I mean conclusion but it doesn't directly affect uh Darwin's idea it still could be that cooking was invented by humans so when was cooking invented and what's happened in our adaptation actually people have known the answer to this I think for years for people have long been aware that our guts got small at one particular point in time and that was almost two million years ago with the evolution of homo erectus because the bones tell us when you have a relatively narrow rib cage and narrow pelvis that signals small guts as opposed to the flared rib cage and the wide pelvis that are designed to help carry the large intestinal system so that goes back a long way and so do the teeth the largest drop in the size of the chewing teeth in the whole of human evolution as we go back from the present into the past here is with the evolution of homo erectus from its predecessor a thing called a habit line so we know when we got our small guts and our small teeth and we know they're associated with our failure to live on raw food so that suggests to me that we have to conclude we've been living despite the archaeological evidence on cooked food for almost two million years A different kind of species suddenly a species that is using external power in a way that no other species has been and then there's another point that people have not sort of noticed I think or thought about which is that the great apes they sleep in trees in place like this he has a nest in a tree okay so if you're a chimpanzee that's fine you can climb up this tree in the gloaming and then treat the branches together and make a nest but any of you who think that fire was not controlled until 200 000 years ago I'd like to challenge you to go and sleep in one of these nests go and climb a tree like this and make a nest in it you know maybe you could do it first two or three times and then you'd fall out and you'd be dead it's very difficult to imagine a species with our kind of body frame being able to do this so that suggests to me that they slept on the ground and if they slept on the ground how did they defend themselves against the natural Predators surely they must have used fire and We Know by the way that Apes like their food cooked and this is suggests that the species that gave rise to Homo erectus very soon after discovering the use of fire in some mysterious way would have been able to used it to cook their food we find that monkeys quite like to take food out of a fire like this one in Japan that has been cooked and and they spontaneously learn to like cooked food we've tested apes and we find that they never prefer their food raw sometimes they don't mind and sometimes they prefer it cooked suggesting that the moment that fire was first controlled then there'd be Apes will be sitting around the fire and food would drop in and because food is scarce they'd pick it out again and say oh this tastes nice let's start a new tradition so here's my idea that what we've got is a shift from conventional wisdom that it was some version of an australopithe scene that somehow learned not only to eat raw meat but also to cook it and then after that we stayed the same shape as we were small guts small teeth and we got bigger brains and became fully human and for those of you who are really interested in these or details of this I'd just like to point out that the way one we should think about it I think is that there was an intermediate phase the harbor lines where they were eating raw meat and processing it with stone tools such as making steak tartar pounding it and and then the cooked food came in a little later so a bit of a two-stage process okay well that is uh the story of human evolution in um far too short a Time there's the conclusion I that cooking first of all gives us energy I absolutely think you can take that to the bank secondly that we are biologically adapted to eating cooked Foods I've looked everywhere for cases of people who have been um isolated in the wild because they've been Cast Away or because they've lost their companions uh living off raw food it doesn't happen uh all of the great explorers who survive periods in the wild are people who have somehow had access to fire so I think that you number two is right we're biologically adapted to eating cooked foods and I can't escape the logic that says that it began with Homo erectus but I'll be fascinated if it turns out that anyone can challenge that in the future but I think that we need to think of ourselves as this species that has moved out of the realm of ordinary animalhood because we can capture external energy and use it to do so many things and I'd like to just quickly look at some of the things that we can do cooking's had huge effects um you might say a difference between Jane Goodall and Fifi is Jane Goodall's brain and it's true that it is three times bigger than Fifi's but to me the thing that just amazes me nowadays is how tiny our mouths are I think of us as the small mouth deep you know any decent ape is is able to open its jaws this big and and this wide and we have these tiny little holes even though we actually eat more calories than the other Apes cooking softens food one of the big impacts on our whole way in which we organize our lives is that we have extended period of childhood during which we look after children and it begins with very early weaning it's difficult to imagine how that early weaning could happen unless the food is soft enough for kids with weak soft teeth to be able to process here's a huge one that Plato noticed and many people have forgotten if we were a chimpanzee we would spend something like six hours a day just moving our Jaws up and down chewing we would not have much time to compose poetry well I suppose well maybe you can compose personality or chewing but a lot of people can't easily chew gum and do other things at the same time um the great apes the chimpanzees I first watched they were spending more than six hours a day chewing it's I'm definitely the australopithe scenes they would be eating very tough food with their big chewy teeth they'd have been spending all that time chewing we eat for less than an hour a day is completely changed the way we organize our lives and if you think about the importance of hunting in human evolution they could never hunt until they had time to do it the current theory about why some species have bigger brains than others targets both the benefits and the costs and the benefits may or may not have something to do with cooking probably not but the costs almost certainly do because among the primates the cost of maintaining a big brain is clearly very severe about 20 percent of our food goes to maintaining just our brains that's how expensive brains are in terms of the calories in order to be able to supply that much energy to one particular organ you have to think about where that energy comes from does it come from us having a high metabolic rate no we have exactly the same basal metabolic rate as expected for every other primate on the basis of our body size so it comes from us having some organ that is reduced compared to others and the organ that is most obviously reduced and associated with big brains in primates is the gut those species that tend to have that happen to have small guts because they happen to eat relatively easily chewed food they have big brains humans have the smallest guts of all we have the biggest brains of all so here's something else that came out of the kitchen just because we cooked it looks as though we were able to spend less of our metabolism on digesting the food and more of it on having big brains it did all sorts of things to our minds too I mean probably patience was needed to be able to appreciate the benefits of putting food onto fires and extracting a few minutes later chimpanzees I think would generally find it very difficult to put food onto a fire and be told sit there and wait for 20 minutes and then eat the food they'd just be gramming it again straight away so patience and cooking are intimately related but once patients are loud cooking then there would be clearly a lot of selection a lot of evolution in favor of being more patient being able to look ahead being able to think about the consequences of your action and inhibit your immediate desires and here's another one which I particularly think is important and that is the relationship between cooking and the sexual division of labor the sexual division of labor is he does one thing she does another they pool their resources and share and no other species does it now mostly people think well this is something to do without being smart maybe it is but I think you can make a pretty strong argument that it is also a consequence of the fact that we cook and basically that it's men taking advantage of women's labor sorry guys you know we don't look too good in this one um because once people started cooking then it's pretty easy to find where someone is cooking and it means that when there is fire when there is smoke then there's you're going to be fairly easy to find some food that's just about to get ready and take advantage of other people's labor and it's easy to imagine that the the bigger more brutal men were doing it to the women regardless of how it started the fact is that as a generalization All Around the World in every society except modern industrialized Urban Society women always do the cooking and in our liberated societies nowadays then there are urban areas in which men quite often do a significant portion of the cooking but still women do most of it and the result is that I think this contributes to the basic asymmetry in men's and women's lives the fact that men have traditionally had so much more freedom to develop so many more professional interests so many more interests of All Sorts uh cooking has contributed to some of the more underlying biological influences on patriarchy and certainly for hunters and gatherers what it does is it enables men to go hunting so the typical kind of thing that happens is the man and woman wake up together in the day in the morning there's not much food available because everyone edit the night before he says well I'm going to go off Hunting and make sure my food is ready for me this evening when I get back at an hour before Sundown and that's what happens and then if in fact it's not if the food isn't ready then there's a scene and a lot of domestic conflict is happens in that particular way in hunters and gatherers um I could go on about the the consequences of the control of fire and cooking but I think you can see that it's been an amazingly potent Force um so it makes me go back to Darwin Darwin said this discovery of fire probably the greatest ever made by man accepting language dates from before the dawn of History it seems to me that it's now an opportunity for us to change his words just a little and say yeah the greatest ever made but not by man and not by woman either but by pre-humans and that this was responsible for many of the changes that have been responsible for this extraordinarily successful species thank you very much we have time for a handful of questions I have a microphone my colleague Scott has a microphone in the back but um you commented on the smaller mouths that humans appear to have but didn't offer any Theory as to whether that's connected to uh Fire Control and cooking do you see any connection yeah no I do um I think it's the softer food and the smaller amount of food that are taken in we still don't have really good data but it's it's very clear from the um these subsistence societies that have been compared with primates that humans actually eat less but get more calories and one of the consequences of cooking is that because our food gives us more calories we can afford to to just have less in our our mouths so I think it's as simple as there's just less going into the tube while they're organizing the questions oh we can't really see this but um I well maybe the point is not really made but I wanted to point out that there are five known individuals in here there's Charles Darwin here and there's Jane Goodall here and the Stephen J Gould here and there's Richard Dawkins here and here is Hugh yes the bonobo yes on Craft cooking and the sociability the evolution of sociability among those um uh Eights well uh yeah uh no it's an interesting question uh so the question is about the comparative sociability of bonobo apes and and humans now bonobos are an interesting species they they're sometimes known as the hippie ape or the erotic ape I they uh have a a relatively relaxed attitude to violence and aggression and a very relaxed attitude to sex as well uh so they're very sociable in a number of ways um but they do differ even from um the uh the height of hippie Dum in the 1960s in a number of ways the females form alliances and will bite the fingers uh uh ends the fingers off the male so these will show a certain amount of aggression they're not just like humans um no there's no connection between cooking and bonobos uh in their sociability then like other wild animals so some of them become more aggressive some less aggressive over evolutionary time the question is absolutely right that I do see strong connections between cooking and sociability and one of them is that as you have uh our ancestors drawn for the first time to spend their nights close to each other around the protective Aura of the fire then that would I think be tremendous advantages in favor of those individuals who did not lose their tempers too easily who were relatively calm and and I think this would probably be a very important selective force in favor of the kinds of relatively gentle personalities that we have now I I'd like to by the way just tell a sort of cautionary tale about the bonobo um you know people get very excited about raw food as diets but they get real excited about diet fads in general um in fact there's a sort of five-step process with with diet fads uh you know you start up being a vegetarian I'm sure there are lots of vegetarians here um then you get say this is a great uh let's become a vegan and a cave and then the next stage is you become a raw foodist now by the way you know you can there are a lot of health benefits you've got to watch yourself a monitor but a lot of health benefits particularly in terms of weight but it gets trickier after that you become a fruit area and after becoming a raw foodist now that's the fourth stage the fifth stage is you're a breatharian and I don't know if any of you have seen the the book about breatharianism by Jazz moheen you know what it's like to be a breatharian the the to be a breatharian you rely on The Prana uh in the air around you you know so it sounds completely nuts and frankly I think it is completely nuts um and uh there was a breatharian in that I know it was a breatharian in the early 1900s who uh advocated uh this and and then died and the sect gave up well you know so that's One Direction you can take well um I I mentioned this just as uh Prelude to actually what's a rather sad it is a sad story about um raw foodism uh taken too far there's a guy called geek load uh Burger uh who started a movement to say that we should really eat like great apes and I met some of his followers in the early 1980s and and I'd been one of the few people who studied the diets of chimpanzees in the wild in some detail so they wanted to know is it 65 fruit and and 35 leaf and how many insects and so on so they really wanted to model their diets on uh the diets of chimpanzees on the premise that were basically just chimpanzees and you know at Harvard that's not true so uh They carried on doing this for a bit and and it was successful they uh group got a chateau outside Paris and they went to live in The Chateau and I've talked to some of the people who were part of this and um and that was fine but then I like our friend up here they got fascinated by bonobos and geekor burger said in addition to having a diet of the chimpanzee let's have the sex life of the bonobo well you know we shouldn't go into this in too much detail because there are probably underage people here but um to cut a long story short geek cloudberger ended up in prison that's the danger don't get too serious about this stuff given the division of labor where am I looking given the division of labor that began with cooking and versus Hunter catering would that help account for the first steps towards one specialization of Labor versus individualization as you raised earlier secondly the beginning of organization of of an organized set of behaviors among individuals Beyond self-defense which is principally the only form of group behavior in animals but we then began to move towards specialization and organization did that in your mind begin with the original division of specialization of gathering and cooking um I like the way you think and in general I think the answer is absolutely yes that I I see cooking as being the origin of the sexual division of labor with all of its consequent elaboration into a lot of complicated role specialization and complementarity the one point at which I would say I would make sure to be um clear that is not as implied I think by your question is that I do not imagine that these would have been isolated pairs or or triplets of individuals in the bush I would already imagine there would be a social organization that it would be probably a male uh set of bonds that would unite some of these small families into a group of you know who knows how many 5 10 15 families and that would have preceded that because that's what we see in the great apes we see a very strong tendency for that and it's and it's very common in subsistence societies and it makes a lot of logic which is that the males defend not against predators so much but more importantly against other males yes but the big issue I was getting at here was one of the things I think that's underappreciated like cooking is the important division in building organization and specialization which is uniquely human to be able to build widely varying specialized and organized tasks yeah no I I mean I think you're absolutely right and and I by the way one of the reasons that I think that cooking is so fundamental is the sort of theory that we could talk about but another was just this very impractical Point people talk about the sexual division of labor being consistent in hunters and gatherers who are our models for how we live before agriculture well if you look at hunters and gatherers it is not true that you always find women getting one kind of food and men getting another there are hunters and gatherers in which women get no food at all in the Arctic because the men get all the food but the women cook it and in Northern Australia the women get almost all the food and the men contribute almost nothing but again the women cook it it doesn't matter where you are how much the women are producing the women are always left cooking the food and subject I'm sorry to say to um pretty nasty treatment by males if they're dissatisfied with what happens just one more example of moving away from a rougher past thank you Dr rangamas please give Dr Raymond another round of applause [Applause]

Channel: Linda Hall Library

Views: 7,867

Keywords: evolution, Darwin, human evolution, anthropology, science, engineering, technology, STEM, STEAM, cooking, food

Id: U0AhARUCy4U

Length: 54min 2sec (3242 seconds)

Published: Tue Apr 04 2023