Instant Genius - How biology has shaped the history of the human race

Episode Date: July 14, 2024

There are currently more than eight billion human beings living on Earth, occupying nearly every corner of the planet. It’s a remarkable situation to find ourselves in, and there can be little doubt that the story of human progress has, by and large, been a successful one. But how did we reach this point? What sets us apart from other animals? And what is it about our biology that has allowed us to achieve this incredible feat? In this episode, we catch up with astrobiologist and author Prof Lewis Dartnell to talk about his latest book Being Human: How Biology Shaped World History. He takes us on a trip through the evolution of the human race. We talk about how human beings’ ability to form harmonious societies has helped us prosper, why we’re so prone to making errors in judgment despite our great success as a species and how the world we’ve built has ended up influencing our biology back in return. Learn more about your ad choices. Visit podcastchoices.com/adchoices

Ambition comes in all shapes and sizes. At First Citizens Bank, we roll with your goals because we're built for what you're building. Fit for your ambition for Citizens Bank. Peak pollination season, and my business is scaling fast. To keep the nectar flowing, I need a phone plan with top priority data speed. That's why I chose GoogleFi wireless. My connections stay strong even when the hive is buzzing.

Plus, unlimited plans started $35 a month. Now that's a deal that doesn't stay. Explore GoogleFi Wireless plans today. Plus taxes and government fees. GoogleFi Wireless is not subject to data traffic deprioritization during times of high network usage. You said this place was steps from the water. We just haven't found the steps yet. How much did we save?

Enough. Enough to get lost! Or you could book a stay with Hilton. Welcome to your oceanfront room. Just steps from the water. The Hilton sale is on now. Book on Hilton.com or the Hilton app and save up to 20% to get the stay you expected.

When you want savings, not surprises. It matters where you stay. Hilton, for the stay. This podcast is sponsored by name, audio and focal. Streaming has made music more accessible than ever, but true listening is about more than ease. It's about quality. British audio experts name audio,

alongside French acoustic specialist focal, combine handcrafted tradition with cutting-edge innovation and high-end materials, delivering digital precision with analogue warmth. So you can experience exceptional sound at home. Music just as the artist intended. Visit name audio.com to learn more. Hello and welcome to Instant Genius,

a bite-sized master class in podcast form. Every Monday and Friday, you'll hear world-leading scientists and experts talking about the most fascinating ideas on science and technology today. I'm Jason Goodyear, commissioning editor at BBC Science Focus. There are currently more than 8 billion human beings living on Earth, occupying nearly every corner of the planet. It's a remarkable situation to find ourselves in,

and there can be little doubt that the story of human progress has, by and large, been a successful one. But how did we reach this point? What sets us apart from other animals? And what is it about our biology that has allowed us to, achieve this incredible feat. In this episode we catch up with astrobiologist and author Professor Lewis Darnal to talk about his latest book, Being Human, how biology shaped world history. He takes us on a trip through the evolution of the human race. We talk about our human being's ability to form harmonious societies has helped us to prosper, why we're so prone to making errors in

judgment despite our great success of the species, and how the world we've built has ended up influencing our biology back in return. So welcome to the podcast, Lewis. Thanks very much for joining us. Thank you, Jason. Thank you for having me. I've been looking forward to this chat. Oh, great. Me too. So today we're talking about your latest book, Being Human, How Our Biology Shaped World History. So this is your third book. So by way of starting, can you just introduce yourself, say what you do, and say how you came to write this book? I'm an astrobiologist. So my research, my science, all about looking to the possibility of life beyond the Earth. So I've come from a biologist background that was my degree. And astrobiology and my research now is all about taking what we

know about life on Earth, what sort of conditions it can survive under, what kind of signs it leaves behind the environment. And then extending that knowledge to places like Mars to see if we could find evidence of Martian bacteria with our next generation of Mars rovers. So that's my day job, if you like, is helping the hunt for aliens. And alongside that, I do a lot of science engagement and public outreach and bits and pieces on TV and radio, but also journalism and writing books. And so being human is my fifth book, but my sort of third big book, my third major book, you see what I mean. And the first of these three was called The Knowledge, How to Rebuild a World From Scratch. And that book is all about imagining there's been some kind of apocalypse,

some kind of global catastrophe that's wiped out most of human race. And the book is about how you could go around recovering and rebuilding everything we take for granted. Could you reboot civilization after an apocalypse in the way you would reboot a computer or, you know, how could you do Minecraft for real when you're going back to sort of basic? So the knowledge is effectively just a history of science and technology and how we built the world that we take for granted around us today. And then Origins pulls out on that perspective to look at how features, of the planet we live on. Features of the Earth itself have been really important for thousands of years of human history and the rise and fall of different civilizations and empires and societies

and cultures. And again, the shaping of the modern world. So it looks at things like plate tectonics, continental drift, and the churning of the atmosphere high above our heads and where different metals or other mineral resources are found around the world. And how all those have been important and shaping the course of history. And then this current book, Being Human, the new book, continues that sort of investigative thread, if you like. So I'm being interdisciplinaries, merging lots of different kinds of science together with history. And I'm now looking at how things which are intrinsic to us, innate things about our humanness, aspects of us as a species have been important throughout human history. And so the book, Being Human,

covers things like our genetics and mutations in our DNA or bits and pieces of our physiology, our anatomy, how our bodies are built, as well as our psychology and things like cognitive biases. So how we make errors in our cognition and our thinking and our psychologies. So it kind of continues that thread that I started with the first two books, but you can absolutely read being human without having touched the others. It's a standalone investigation into us and how we built our own history. Great. So let's have a look at some of the things

that you cover in the book then. So you start out with the key feature of humanity, and that's the way that we live in groups and form societies. And you talk about sort of two prongs that helped this occur. So the first is to do with aggression. So what happened there, and how did that help?

Yeah, so one of the central features of humanity, of modern humans is how overall we're very, very peaceful. We're not constantly lashing out and committing acts of aggression against each other. And that is absolutely critical for a society, for large groups of humans living together and, you know, not constantly bashing each other and erupting in violence. And particularly for civilization, which is effectively a huge group of people, all pulling together in the same direction, all collaborating and working together. And when you compare humans to even our closest common ancestors, so closely related species like chimpanzees or the bonobos, we are much, much more peaceful than them. We are aggressive to each other, far more rarely. Although humans do express a different kind of violence, which is sort of organized violence.

Humans definitely go to war. We definitely are aggressive to each other. But it's a different kind of planned aggression rather than hot-headed, sort of angry aggression, which is what we see most of in things like chimpanzees. So you mentioned there the idea of human beings being excellent cooperators. So what's so special about that? I mean, it's a necessary prerequisite for a complex society and civilisation. We have to be able to work together, but also to trust each other. One of the key problems with cooperation in biology is effectively catching cheats. If everyone a group of people benefits from, you know, an antelope being successfully hunted, for example, because it means you don't go hungry. What you want to be able to ensure is that

everyone in that group is contributing fairly to the outcome. And you don't have people being a bit lazy and pretending to run, but not really putting their back into it. And effectively cheating on that collaborative exercise. They're getting the benefits, but they're not paying the cost in energy or time or resources or whatever it is. And one of the things we've seen from a lot of psychological experiments in humans is we're very, very good at cooperating with each other. And we sort of self-police that cooperation by actively trying to catch people who are cheating. People aren't pulling their weight. People who aren't contributing equally. And it's one of these fascinating results that comes out from a huge range of cognitive psychology and experiments and errors research into our behavior and how

well we work together with each other. So you mentioned there cheating. So where does the sort of the notion of punishment of wrongdoers come from? Yeah, so you need to not only be able to catch cheats and things like language clearly help there. You know, gossip has a fundamentally important role within complex societies like humans live in because it's fundamentally, exchange of information. You're talking about each other. You're talking about other people. Has someone been a good person? Did they help you out next time? Are they therefore someone that would be worthwhile acting altruistically to next time, helping out in turn? But also discussing when people haven't behaved particularly well, or least particularly altruistically or cooperatively. Maybe they

cheated you in the past. Maybe you witnessed them cheating someone else. And so gossip is a very, very primitive form of something like the internet, where it is sharing information across the network of people so that you can start getting an idea yourself of who's likely to be reliable and trustworthy and worth cooperating with yourself or someone you might want to avoid, which is itself a form of punishment, not interacting with someone, not sharing something with them, is itself a punishment, or taking it to the next level where you might then start escalating to things like aggression and violence, which I say we do see in human societies. When you need to build up your team to handle the growing chaos at work, use Indeed

sponsored jobs. It gives your job post the boost it needs to be seen and helps reach people with the right skills, certifications, and more. Spend less time searching and more time actually interviewing candidates who check all your boxes. Listeners of this show will get a $75-sponsored job credit at Indeed.com slash podcast. That's Indeed.com slash podcast. Terms and conditions apply. Need a hiring hero? This is a job for Indeed sponsored jobs. No one goes to Hank's for his spreadsheets. They go for a darn good pizza. Lately, though, the shop's been quiet.

So Hank decides to bring back the $1 slice. He asks Copilot in Microsoft Excel to look at his sales and costs to help him see if he can afford it. Co-Pilot shows Hank where the money's going and which little extras make the dollar slice work. Now, Hanks has a line out the door. Hank makes the pizza. Co-Pilot handles the spreadsheets.

Learn more at M365Copilot.com slash work. This podcast is sponsored by Name, Audio and Focal. With over 100 years of combined expertise, Name and Focal have been bringing music to listeners just as the artist intended. Since day one, this mantra has shaped every innovation in high-fi design, technology and acoustic engineering, balancing craftsmanship and tradition with pioneering thinking.

Name Audio pushes cutting-edge technology to ensure digital precision whilst sustaining Pratt, pace, rhythm and timing, the elusive quality that makes music feel alive and gives it emotional texture. Today, in partnership with French acoustic specialist focal, name audio creates systems that deliver exceptional sound and unforgettable listening experiences at home.

Try it for yourself at a focal powered by name boutique. Visit focal powered by name.com for more information. So moving on from that then, let's look at the notion of rules and laws. So in the book, you talk about something called the Code of Hammurabi, which was like a public declaration of rules and laws. Yeah, so humans are innately good at cooperating and working together in society and catching and punishing cheats. But that only takes you so far.

That only works in relatively small groups of people, like bands of hunter-gatherers that we existed in in our ancestral states, our ancestors lived in. And in the modern world, clearly you interact with far, far more people. I pass more people on my commute in London where I live into work than one of my hunter-gatherer ancestors probably encountered in their entire lives. We live in immensely dense human populations nowadays. And we simply can't keep track of the people we come across who's trustworthy, who's reliable, who should we avoid, who is cheated in the past, who is cheated in the So we can't rely on our innate abilities in doing that.

And so in order to build much more populous and complex societies and civilizations, we've had to codify those into written laws. And this is what the code of Hamer Abai is. It's one of the earliest examples, one of the early surviving examples of written rules. If you do this bad thing, you'll be punished in this way. But when you look at these early codes of laws and clearly the laws of the land that we all live under today, all of them are fundamentally based on what we would be wanting to avoid anyway. You know, our innate aversion to aggression or to violence or are aversion to watching someone steal someone else's stuff. It's just codifying what we would have been doing otherwise.

So let's sort of go from the wider population at large to perhaps the sort of fundamental unit. of human society, which is the family unit. So human babies are particularly vulnerable when they're first born. You know, they even take a long time to walk. All you've got to do is look at something like a giraffe as soon as it's born. Shortly afterwards, it's up and about. So how has that influenced this notion of the human family unit? Yeah, so throughout the book, throughout being human, I try to start with deeply fundamental things about us, about our psychology and our ability to cooperate as we've just been talking about, or how we reproduce and the human family, and then work through history showing the deep implications of that biological fact.

Like, how has this had an influence? How has this had an effect through history? And the fact that humans are very, very intelligent, we have big brains, and we're also bipedal. We walk around on two feet. feet is something of an evolutionary problem because human babies are born by squeezing the skull through a hole in the pelvis of the mother. And walking upright serves to constrict the size of that hole in the pelvis and being intelligent, having a big brain is liable to get stuck in that. So being bipedal and being big-brained are at loggerheads with each other. They are in direct conflict. And so the solution that evolution found in human lineage was to give birth to small,

brained babies and allow the brain to continue growing for long period after birth. And that's the fundamental reason why human babies and infants are incredibly dependent on their mother, incredibly vulnerable for the first couple of years of life, compared to basically any other animal, any other mammal. And that means that it puts such a large demand on the mother's time and energy and resources for finding food that basically a single mother couldn't do that historically. Couldn't do that ancestrally. So the father has to help raise the child as well. And that in itself is also something of a rarity in the animal kingdom. This bi-parental investment where both mother and also father are helping raise a child. And you've got to bind together

mother and father for long enough to get their baby, their child through those vulnerable early years. And this is done by something called pair bonding, which we also see in birds. And it's a link forged between a mother and a father, a male and a female, by a hormone called oxytocin. And we experience that as humans, we experience that as romantic love. Love is the emotion we feel from this biological imperative to stick together as a couple long enough that your baby thrives and survives. And out of that comes the human family. And that is a direct consequence of our evolution towards being intelligent and bipedal,

which gives us pair bonding, which gives us romantic love, which gives us that nucleus of the human family. And that, of course, has been hugely transformative, hugely influential throughout human history. And some of the stories I explore in the book in being human are elite families, monarchies, royal families, and how they exploit their biology to retain power, to stay in the throne. So sort of coming off the back of that then, kind of baked into this idea of family unit, is the idea of the inheritance of property, and the natural end point of that is that some become wealthier than others. So what effect has that had?

Yeah, so we inherit lots of things from our parents. We inherit things like our eye colour or any other physical attribute you might like to point at. But with complex society and civilisation, and particularly with the advent of agriculture and being sedentary, sticking around in villages and towns and then cities, we were able to start amassing material wealth,

but also laying claim to particular territories, to land that we said that we owned. And therefore, children began to inherit not just things from their parents' genes, but also their parents' possessions, wealth, resources, territory. And that started this process of the rich getting richer, where elite members of society become more and more wealth. and therefore more and more powerful and having control over greater, greater areas of territory.

Until in a certain period of history, you're talking about not just kings and queens, but emperors ruling over enormous areas of land, and their children inheriting that power. And one of the stories I look at in being human was one of arguably the most prominent royal families in European history, which were the Habsburgs. and through a very cleverly and carefully orchestrated system of royal marriages. They worked out which were the other royal families were the best ones to marry into, married off their sons and daughters, and effectively just accumulated huge areas of Europe under their domain,

but they just collected thrones, they collected territories, and so the Habsburgs were absolutely the masters of the game of thrones through hundreds of years of European history. The problem with that, though, and this again brings us right back to biology, is if you are constantly marrying within the same families, and particularly within the line of kings, there was the incentive to marry close relatives so that other families don't have a claim to your family's throne. You can cling on to that power. You're effectively inbreeding.

You're starting to concentrate deleterious genes, deleterious mutations in the genetics of each generation. and it builds up over time. And this became a huge problem within the Spanish Habsburgs, within one of the two halves of the Habsburg royal families. And it became very obvious in even their faces. They had this pronounced Habsburg jaw. And many of the Habsburg kings even struggled to eat properly because of the effects of this inbreeding

and the accumulation of deleterious mutations. They started suffering from problems reproduction with lots of birth defects. and miscarriages. And it all came to head with Charles II, who was the last Spanish Habsburg King, and he seems to being congenitally unable to have children. Like the only thing that this dynasty, that this long-lasting, powerful, royal family needed of him was to simply reproduce, to just have a child, ideally a male child, because sons were preferred for kings. And he was unable to do that. and the entire dynasty died out.

It drove itself to extinction because of this long-running program of effectively inbreeding, trying to cling on to that power. And the war of Spanish accession that resulted from that shifted that the power balance across the entire continent.

So again, in this story, go from fundamental things about our biology, about our humanness and why we have pair bonding which leads to marriage, why we have human families and the inheritance of wealth and power. And what were some of the profound knock-on effects of that

through hundreds of years of history? And the shaping of the world that we see today, like where different countries are today comes from that process of the accumulation of kingdoms. So let's shove gear slightly here then. Another attribute of humans, unfortunately, as we found out over the last five years, is our susceptibility to infection and disease.

So how has that shaped the evolution of humanity? Well, I mean, it's shaped our evolution. in terms of every time there's a new disease breaks out into a population, it often kills large numbers of people. And the survivors will have some level of, likely to have some level of immunity, which then gets passed on to the next generation. So disease is one of the fundamental things which drive selection, drives evolution of our species and other species. But I also focus in the book about how different diseases have shaped societies, have shaped civilization and the course of history. And one of the outcomes of the black death, the bubonic plague, seems to have been a shifting the balance of power within society in Northern Europe, and particularly Britain, where it

killed off a large number of people, and there weren't enough people left behind to work the land. So in the feudal system at the time in the 14th century, there was a Lord of the Manor who had dominion over a large area of land and peasants who were beholden to him that worked that land. Now with far fewer people alive, the value of labour shot up. You really want to be able to hang on to your labourers to work your land, whereas the labourers started getting a bit more freedom to move around. So it was sort of loosening the ties of the feudal system, starting to move toward more of an economy based on money and financial transactions, rather than effectively being stuck to the land where you were born. So that was one of the effects of the bubonic plague.

Another of the stories I look at in the book is how the political union of England and Scotland came about because of tropical disease on the other side of the planet in the tropics of Panama in Central America. And this comes down to the Darien scheme, which was a Scottish project, a Scottish bid to build more of a mercantile economy like the English when enjoying at the time of trading with ships and taxing and generating money by overseas colonies. and they built a colony, a new Scotland, in the tropics of Panama, but it got absolutely devastated by tropical diseases, by yellow fever, by malaria.

And the colony failed, the colonial project failed, and with it was lost a huge amount of the money that we put into it. So Scotland was financially weakened after failure of this colonial effort and shift the balance of power so that England could effectively force Scotland into this union. So, you know, something fundamental about the relationship between England and Scotland today, the United Kingdom, came about because of disease, you know, hundreds of years ago. So sort of vaguely related to that is the notion of changing demographics. So these days, a lot of people are talking about falling birth rates in developed countries. So how has demographics changed as human society has changed in shape and structure?

Yeah, so demographics describes large-scale. properties of our population, so the birth rate, how quickly new people are being born, the death rate, whether your society has mostly young people or older people. And that sort of structure of your population has important knock-on effects to how the society behaves, what sort of things it does. And one of the examples I look at is when the sex ratio becomes significantly distorted from a 50-50 mixture of men and women, which is what you have, an enormous, healthy population. And particular events in history have strongly distorted that ratio. In particular, war, war tends to kill young men, the soldiers die on the battlefield. And Russia after the

Second World War had an enormous deficit of fighting age men. The transatlantic slave trade also preferentially took young men from their homes in Africa and took them across the colonies. So the societies left behind, the population left behind became female biased. Whereas we saw the opposite happening in Australia after the penal colonies when mostly men were being taken to Australia. Even for several generations afterwards, there was a male-dominated population structure. And historians and anthropologists and sociologists have looked at what happened to the societies, over the generations, after there had been this distinct distortion and the sex ratio, and the effects it had on things like whether women are likely to go to work, or whether they're

likely to stay at home and perform the role of a housewife, for example. So we have this fascinating outcome where something that happened hundreds of years ago fundamentally affected the biology of the population, the demographics, the population, and became locked in to the expectations and the cultural norms of that society. So it, it's a very important. So it's a lot of the population. So even in the world today, we see that societal fingerprint of something that happened in the past. So at the start of our conversation, you mentioned you cover psychology. And this is really interesting, that certain ways in which humans operate sub-optimally. Yeah. So I'm talking about, as you said, cognitive biases. So, you know, what are these and how do they affect us?

We know what we could do if you wanted. We could do a quick-fire quiz. I've got three questions which our listeners can think to themselves what the answers they think they might be. So the first question is, do you think you're more likely to win the EuroMillions lottery jackpot or be killed by a vending machine? And what you need to do here is go with your gut response. What is the first answer that presents it to yourself rather than trying to outthink the question and go, well, this is a trick question, obviously, so I'm going to go not with my gut impression, but what I think it might be. So just go with the first answer that occurs to you. Are you more like to win the Euro-Millian's lottery jackpot or be killed by a vending machine?

The second question is, do you think there are more words in the English language that start with the letter K or that have K as the third letter in the word? Do more words start with K or have K as the third, specifically the third letter? And then thirdly, do you think you're more likely to die in a car crash or a plane crash? And I think that last one you may well have come across before. And it is the case that you are much, much more likely to die in a car accident than a plane crash, but you might not have thought that because plane crashes tend to kill lots of people all at once. It tends to make the headlines.

It's a shocking. It's an atrocity. It's a catastrophe. You tend to remember that. So you have this cognitive bias. You think that plane accidents are more likely to find easy to remember instances of when it happened. And for similar reasons, there are more words in the English language that have K is the third letter, not beginning with it. And you would struggle to believe this because it's very easy to come up with

words beginning with K, where that's kick or kangaroo or ketchup, and harder to think of words that have K specific as the third letter, like ankle or bakery. We just find it harder to generate those words. So we think there's less of them. And again, you are more likely to be killed by a vending machine than you are to win the euro millions lottery jackpot. And this isn't because you might have gone down some dark alley late at night and be jumped by a vending machine holding a, a flick knife. The source of these vending machine deaths are people being frustrated that they've put in their money and their kit-cattle twicks hasn't come out, or they're being a bit cheeky, they're cheating society like we spoke about earlier. And they're trying to get a chocolate

bar without having paid for it. So they're rocking the vending machine, trying to shake one loose for free. And unfortunately, over topples and crushes them beneath its weight. And at least a couple years ago, I think that may no longer be true because there's been a public health campaign to stop people killing themselves by vending machine. But there was a period a few years ago when more people were dying per year by vending machines than winning the lottery. And all of these examples are of cognitive bias, of a particular cognitive bias called the availability bias. We think something's more likely simply because we find easier to think of examples of it. And there's huge numbers of cognitive biases, these glitches or bugs, if you like, in our

software, in the programming of our psychology. One of the ones I talk about in being human is about the confirmation bias and Columbus. And the confirmation bias is you think you are right and you're so sure that you are right, you effectively start ignoring all the evidence that you're not, that you maybe should rethink, you should reconsider what you'd previously held to be true. And Columbus is a very, very good example of his confirmation bias in history, because he made four separate voyages across the Americas in the end. and until his deathbed, he never accepted, he never realized that he had never reached the Orient, China or India, which is where he was trying to sail to.

He'd reached somewhere else completely different. He reached a new world. And he just ignored all the evidence that was telling him that he had reached a new world and was just clutching at straws. He was cherry-picking things which supported him. And so this is something of a historical curiosity. It's a well-known famous example of confirmation bias. But it's also a general problem of how we reassess our beliefs. And more recently, confirmation bias was a very significant effect, a psychological effect, behind the dossier of evidence that was collected that was ended up using to support the invasion of Iraq in 2003. So this huge war were started because of confirmation bias and people, analysts, looking for evidence to support the belief that Saddam Hussein had weapons and mass destruction. He didn't. It became very rapidly clear.

As soon as the invasion has started, he'd never had anything of the sort, but the analysts had been cherry-picking things which supported their prior belief, rather than thinking again, rather than just stepping back and saying, look, let's just start from scratch, what is likely to be the case, rather than just looking for stuff that supports what we already believed. And it's also, you know, affecting how we're able to address climate change. People stick to their guns. People find it difficult to change their prior beliefs, their prior opinions.

And we see so much that nowadays on social media, on Twitter, X or Facebook, with people just doubling down and becoming entrenched in their prior belief, rather being open-minded and be willing to admit that perhaps they had been wrong in the past and changing their mind. It's a really difficult thing to do publicly. we've talked about an awful lot of things there. So sort of by way of closing, let's move right up into the modern world. And so we've talked about how human biology has influenced human society and how it's grown, etc. But these days, the modern world that we've created is

affecting us in return. So what's happening there? Yes, I spend most of the book focusing on ways that features of us as a species has affected history. But the reverse process, process is also true. We've affected our own biologies. We've driven our own evolution in particular directions through choices we've made in history. And most significantly, with advent of agriculture and the growing of cereal crops to feed ourselves and the domestication of animals and particularly dairying. So keeping animals to drink their milk, not just cows, but also goats, sheep, Camels are milked as well. And in that particular example, for some people around the world whose ancestors adopted dairying and milk became an important part of their diet, their DNA was changed.

They continue to express the enzyme that you need to digest milk beyond their infancy, beyond the first year or two when we'd be naturally drinking milk as a baby. And a lot of people in Europe, for example, continue expressing this lactase gene, right through their entire life. And so that is a genetic change. That is a change in our genetics, driven by choices we've made in history. And clearly technology is affecting our biology

and how we live as well. I don't have perfect eyesight. In the past, I would have struggled. Maybe I wouldn't have seen a line until it's too late. But with modern technology, I can wear a pair of glasses and have perfect 2020 vision.

So that last chapter, I look at lots of different ways that the reverse process has happened and how things like obesity and diabetes are effectively diseases created by this mismatch between what evolution is expecting to find and how our bodies have been crafted over evolution history and the modern world we live in where things like fat and sugar are incredibly easy to come across and you can pop down to the local shop and a tiny amount of money get something which is far far more rich than our ancestors would ever had available

So it's how biology is biting back in the modern world, if you like. Thank you for listening to this episode of Instant Genius, brought to you from the team behind BBC Science Focus. That was astrobiologist and author Professor Lewis Dartmoor. To discover more about the topics we've just discussed, check out his latest book, Being Human, how biology shaped world history. If you liked what you just heard, please do consider subscribing to Instant Genius on your podcast platform of choice. The current issue of BBC Science Focus magazine is out now. Pick up a copy wherever you buy your favourite magazines

or download us on your preferred app store. You can also find us online at sciencefocus.com. This podcast is sponsored by Name, Audio and Focal. The texture and emotional depth of music can be lost through digital sources or poor signal. Name Audio believes you can have digital precision with analogue warmth. Alongside French acoustic specialist vocal,

Name creates high-end audio systems, combining innovation with craftsmanship, so you can listen to music, just as the artist intended. Discover more at nameaudio.com. Relax and let Ralph's delivery handle your grocery shopping this week. We start with only the freshest items, then review your list and carefully choose each one.

Then we pack it all up and deliver it in as little as 30 minutes. so you can feel confident it's what you ordered. Fresh groceries, your way, with Ralph's delivery and pickup. And right now, you can save $20 on your first delivery or pickup order. Ralph's, fresh for everyone. Did you know if your windows are bare, indoor temperatures can go up 20 degrees? Get ahead of summer with custom window treatments like solar roller shades from blinds.com and save up to 45% during the Memorial Day Early Access Sale.

Whether you want to DIY it or have a pro-hand. everything. We've got you. Free samples, real design experts, and zero pressure. Just help when you need it. Shop up to 45% off site-wide right now during the early access Memorial Day sale at blinds.com. Rules and restrictions apply.