The Reality of Being Santa

Could Santa Clause still exist IF we stripped away the magic? If the ability to bend spacetime was gone? What conditions would Santa need to deliver a present to every human being on Earth in a single night? Hannah Fry and Michael Stevens explore the historical, geographical, and logistical realities behind these questions using population data, longitudinal lines, mathematics AND a healthy dose of Christmas curiosity to calculate the impossible routes, speeds, and time spans involved in a 12 hour gift giving bonanza at global scale as a completely average human being. Wish them luck! ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit ⁠⁠https://cancerresearchuk.org/restisscience⁠⁠ Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Find The Rest Is Science all over the internet by ⁠⁠clicking here.⁠⁠ ------------------- Video Producer: Adam Thornton Video & Social: Bex Tyrrell Assistant Producer: Imee Marriott Producer: Becki Hills Senior Producer: Lauren Armstrong-Carter Head Of Digital: Samuel Oakley Exec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

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• 0:00Hannah Fry?

  This episode is brought to you by Cancer Research UK.

• 0:02Michael Stevens?

  Dinosaurs walked the Earth 180 million years ago. But you know, cancer was part of their story, too. Scientists have found tumors in ancient fossils.

• 0:13Hannah Fry?

  Well, that is a part of the reason why cancer is a big, big part of our story, right? It's the other side of evolution. It's the most complex disease that we face. There are more than 200 types of cancer in total, each with distinct characteristics, challenges and mysteries.

• 0:28Michael Stevens?

  And that complexity demands scale. Cancer Research UK is the world's largest charitable funder of cancer research, with more than 4,000 scientists, doctors and nurses working across more than 20 countries in the search for answers. And then sharing their discoveries beyond borders.

• 0:45Hannah Fry?

  And the impact of this collaboration is clear, because over the last 50 years, the charity's pioneering work has helped to double cancer survival in the UK. That is, more people who are living longer, better lives.

• 0:57Michael Stevens?

  Fossils can show us the past, but research is shaping the future. And for more information about Cancer Research UK, their research, breakthroughs, and how you can support them, visit cancerresearchuk.org/restisscience.

• 1:14Speaker 02

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• 3:22Michael Stevens?

  Hello and welcome to The Rest Is Science. I'm Michael Stevens, creator of the Vsauce YouTube channel.

• 3:27Hannah Fry?

  And I'm Professor Hannah Fry. Welcome to our Christmas edition.

• 3:30Michael Stevens?

  Yeah, look at us. We're in our Christmas jumpers.

• 3:33Hannah Fry?

  I have actual tinsel.

• 3:35Michael Stevens?

  You have actual tinsel on yours? This, this isn't very Christmas themed. It's like a cat in a potted plant. But my wife bought matching jumpers for me, her and my daughter, for my daughter's first Christmas. And it's what we wore. And so for me, it's very, very Christmasy.

• 3:52Hannah Fry?

  Yeah, it's, it's the real true heart of Christmas, right? The fact that you get to be connected with family.

• 3:57Michael Stevens?

  That's right. And today we're going to get to the heart of Christmas. I'm talking physics. I'm talking Santa Claus. Okay. Now, there's an old chestnut, an old roasted chestnut, where physicists talk about, could Santa really do it? Okay. How could Santa visit every single child who celebrates Christmas across the world in one night only?

• 4:21Michael Stevens?

  And without magic, or without some kind of fancy alien technology, it's not possible.

• 4:27Hannah Fry?

  Obviously, what Santa is doing is compressing spacetime, right? In front of the sleigh, he's using an Alcubieri drive. He's expanding spacetime behind him. He's like surfing the resulting bubble faster than the speed of light. Classic Santa physics, easy.

• 4:43Michael Stevens?

  True. And I think the Alcubieri drive would also protect Santa from G-forces.

• 4:48Hannah Fry?

  Yeah.

• 4:48Michael Stevens?

  Because, just for those who aren't familiar, an Alcubieri drive is a hypothetical method of transportation where instead of propelling yourself through space, you change space itself. You can compress space ahead of you and travel light years at a time, in a blink of an eye. And you're not violating physics because you aren't moving faster than light. You aren't moving anything faster than light, you're just changing the shape of space.

• 5:11Hannah Fry?

  Exactly, except that it's not hypothetical because we know that that is the only way that Santa could be.

• 5:16Michael Stevens?

  It must exist because Santa somehow manages to do it. That's correct. Without such a drive, Santa would be experiencing 17,000 times Earth-gravity forces as he twisted and turned.

• 5:29Hannah Fry?

  I guess the thing is Santa hasn't had much competition over the years, right? Probably because he's mastered how to warp spacetime. But if you, if you sort of take that away, was there a point in history where Santa could have existed using only the powers of physics that are available to us mere mortals?

• 5:48Michael Stevens?

  Today, Hannah and I are asking, when could a regular person have competed with Santa? When could you also have visited every living human in one night and given them a gift?

• 5:59Hannah Fry?

  Because right now, you've got 8 billion people on the Earth, right? This is, it's too many. We're all spread out, we're all over the place.

• 6:05Michael Stevens?

  Too spread out.

• 6:06Hannah Fry?

  If we rewind the clock a little bit, I think we, I think we might be able to give Santa a run for his money.

• 6:11Michael Stevens?

  All right, so first things first, let's understand who Santa is. Like, let's rewind the clock, where does it all begin?

• 6:18Hannah Fry?

  The story of Saint Nicholas, I think everyone sort of knows that that's roughly the lineage of Father Christmas, but he is quite the historical figure. This is a Greek bishop in the fourth century, a real person. He was, he was kind of famous for defending Christianity, also for giving gifts. But specifically, he, there are stories about him giving gifts to a poor father who had three daughters, didn't have any money for a dowry. So Saint Nicholas decides to drop off bags of gold, just to make all their lives much better. But one version has him throwing the gold in through the window and it landing in their stockings that are drying by the fire.

• 7:00Michael Stevens?

  Oh, so that's where the stockings come from?

• 7:03Hannah Fry?

  That's where the stockings come from. This is kind of a real person. I mean, I think some of it is slightly embellished over time, I'll be honest with you.

• 7:08Michael Stevens?

  When did this happen? When was Saint Nicholas supposedly alive?

• 7:13Hannah Fry?

  This is fourth century around about. He also was present at the first council of Nysia. And there was this big heated theological argument between him and one of the priests. And Saint Nicholas lost his temper, punched him in the face, which means that that tradition of Christmas arguments is also, stems directly.

• 7:39Michael Stevens?

  Oh, I love that.

• 7:41Hannah Fry?

  Stems directly.

• 7:42Michael Stevens?

  I love that.

• 7:42Hannah Fry?

  One of the other stories about him, by the way, is that he, there was some innocent men, three innocent men, sailors, I think, who were about to be punished, beheaded in a town square. And there's a story that apparently Saint Nicholas appeared out of nowhere, teleported, in my opinion, and appeared at the moment of beheading and grabbed the sword of the executioner, saving these innocent men from, from being executed.

• 8:11Michael Stevens?

  Hannah, is anyone really innocent?

• 8:17Hannah Fry?

  No.

• 8:17Michael Stevens?

  Thank you. We can investigate that more in a future episode. So this is all happening, you said, in like the fourth century. That means the 500s.

• 8:25Hannah Fry?

  Okay, so this, to Saint Nicholas, we're talking 300. We're talking the 300s. That's where we are.

• 8:30Michael Stevens?

  So the 300s, which is the fourth century since time zero.

• 8:35Hannah Fry?

  Yeah.

• 8:35Michael Stevens?

  And, golly, that's a long time ago.

• 8:38Hannah Fry?

  Yeah. So here is the thing, okay. Imagine being like a famous person now, right? Like, you know, Taylor Swift, right? The biggest star in the entire world.

• 8:48Michael Stevens?

  Every day.

• 8:49Hannah Fry?

  Now imagine it being 2,000 years later, 1,700 years later, and her still being so famous that is recognized around the world. Her sort of, her, the kind of metaphorical version of her is still recognized around the world. That is phenomenal work. I mean, what a guy. There's one more thing, actually, about Saint Nicholas that remains a great mystery to this day. So his bones are in Bari in Italy. They're in this tomb. And actually, there was this really big, dramatic event where people went in and stole his skeleton seven years after his death. It came under the control of the Turks and then took it to Italy.

• 9:34Hannah Fry?

  Anyway, his bones were put in this tomb in the year 1,087. And ever since then, every year, it secretes a liquid from the inside of the tomb. And every year, they go in and they collect the liquid. It's about 50 mils of liquid. And the Catholic Church say this is a supernatural event. The secretion of the bones of Saint Nicholas.

• 9:58Michael Stevens?

  I have never heard of that before.

• 10:01Hannah Fry?

  They call it manna, and they dilute it with holy water and sell it.

• 10:05Michael Stevens?

  And they sell it.

• 10:07Hannah Fry?

  It's probably condensation, I've got to be honest with you. But don't worry about that. Don't let that stand in the way.

• 10:11Michael Stevens?

  It might contain some traces of human remains. Not just human remains, Santa remains.

• 10:16Hannah Fry?

  Santa remains. I also think that it could just be that he wants everyone to know that his bones are magical before he sort of left his earthly body and, you know, became the Santa that we know today.

• 10:28Michael Stevens?

  This is really deep. I mean, I really love how immortality can be achieved if you're willing to allow your ghost to like completely change into something different. You know, I think Saint Nicholas was probably like, yeah, Christmas is about Christ and the birth of our Savior. And now he's like the counter choice. It's like, well, you know, uh, because Santa doesn't do any religious stuff. It's not like he-

• 10:54Hannah Fry?

  Uh, he brings happiness to all men and women and children. Uh, that's, that's, that's a pretty religious thing, isn't it?

• 11:00Michael Stevens?

  I mean, I grew up in like the kind of church that was very much like Santa is essentially an arm of Satan because it distracts from the true message of Christmas and the grace of the Lord.

• 11:13Hannah Fry?

  Wow.

• 11:14Michael Stevens?

  Um, and instead we all go, ooh, let's buy things, let's give gifts, right? And the gift came from Santa, not Jesus. Like, he's kind of like the boring part of Christmas.

• 11:25Hannah Fry?

  What church was that?

• 11:27Michael Stevens?

  Uh, well, it would have been like nondenominational Protestant, bordering on evangelical.

• 11:31Hannah Fry?

  I was brought up Catholic and we were fine with it.

• 11:33Michael Stevens?

  You guys were fine with it?

• 11:35Hannah Fry?

  Fine with it. My Irish mom less so, but the, the, the church in general was okay with it.

• 11:39Michael Stevens?

  Right.

• 11:40Hannah Fry?

  This is the guy we're up against, right? He's got a long, old history. He's been famous for millennia. He's got magical bones. He, uh, he throws coins into stockings through windows. He teleports executions and saves innocent people from, from death. You know, you, you're up against a lot before we've even started with the presents.

• 12:00Michael Stevens?

  Yeah.

• 12:01Hannah Fry?

  I think we just have to accept that we can't compete with any of that stuff, but-

• 12:04Michael Stevens?

  Actually, no, Hannah, Hannah, Hannah.

• 12:06Hannah Fry?

  Hmm.

• 12:07Michael Stevens?

  I plan to compete with that. I, I plan on also having weeping bones. There are services that you can pay for that will make sure your bones create liquid for millennia.

• 12:21Hannah Fry?

  Okay.

• 12:22Michael Stevens?

  But anyway, the bones aren't really what we're after. We're after delivering gifts to every human-

• 12:27Hannah Fry?

  Exactly.

• 12:28Michael Stevens?

  -in one night. We're gonna have to find a time in history when there were fewer people. Uh, the first thing we talked about Hannah was population bottlenecks.

• 12:36Hannah Fry?

  Mm-hmm.

• 12:37Michael Stevens?

  These are moments where, for various reasons, the human population like shrunk or, or couldn't grow and it stayed somewhere really low. Like, the first thing I thought of was the Toba bottleneck, which is hypothetical.

• 12:51Hannah Fry?

  Big volcano in Indonesia, right?

• 12:53Michael Stevens?

  Yeah, what, like 74,000 years ago? It affected the climate massively. The the main theory is that the ash cloud would have changed the weather, the amount of sunlight getting to Earth, the temperatures on Earth, and it would have been very hard for early Homo sapiens to live and to thrive. So the the population of of of humans on the entire planet may have dropped as low as like 70,000.

• 13:19Hannah Fry?

  Because when you say that there was a lot of ash from this volcano, I mean, we're talking, we're talking, this is the apocalypse, basically.

• 13:25Michael Stevens?

  Yeah.

• 13:26Hannah Fry?

  I mean, this is like 2,800 cubic kilometers of material.

• 13:30Michael Stevens?

  Gee.

• 13:31Hannah Fry?

  Basically enough ash to cover the entire UK in a layer that's that's taller than Big Ben.

• 13:37Michael Stevens?

  Wow.

• 13:38Hannah Fry?

  I mean, it's phenomenal, the amount of ash that this thing spat out. But but there are some people that think there was like 10 years of volcanic winter, that, you know, plants would have suffered, that, you know, access to food more generally would have been really difficult. And and there was a theory in the 90s and early 2000s that actually, almost all of humanity was wiped out, right, by this by this event.

• 13:59Michael Stevens?

  Yeah, we almost didn't make it. In fact, the the original theory was that at some point, maybe 74,000 years ago, there were only like 1,000 humans on Earth. And we are all the descendants of those thousand who survived the Toba super eruption. Now, that's a sad story, but we're bringing it up because as tragic as that moment could have been, it would have been wonderful for us trying to compete with Santa, because there's only 1,000 people. And, you know, you could, if you could ride around on like a reindeer, all right, just or have them pull a sleigh, they can, they can sprint at like 80 kilometers an hour, all right?

• 14:43Michael Stevens?

  You could visit a lot of people in a night, because you've got, how how many hours of night? Like 30, more than 30 hours?

• 14:49Hannah Fry?

  Well, yeah, I mean, it depends on on how far north you are, I guess.

• 14:53Michael Stevens?

  It does depend on how far north you are. That's how long the night is going to be. Luckily, you can do this in the winter.

• 14:58Hannah Fry?

  Hmm.

• 14:59Michael Stevens?

  So, okay, if you're in the northern hemisphere, you're going to have a much longer night. You can follow that Terminator line of night and day as it goes around Earth. And once you go get back to where you began, guess what? You've still got a whole night ahead of you.

• 15:12Hannah Fry?

  Yes, because as long as you don't cross the date line. So if you start like, you know, right on the date line, but ever so slightly to the west of it, and you only travel west, you have 24 hours to get back to that same point, and it's still be the turn between night and day. But then you can wait there, not cross the date line, all of night time. So if you've got, if you're, you know, far north enough where you have sort of 16 hours of night time, then you've got 24 hours plus 16, well, you have 40 hours.

• 15:39Michael Stevens?

  Wow.

• 15:40Hannah Fry?

  As long as you start at sort of 4pm, I mean, you're gonna, you're gonna struggle to sneak down people's chimneys without being spotted if you're doing it at 4pm. But in theory, you know, you can, you can use the night to your advantage. One of the big counter arguments about the, the Toba super eruption, the kind of catastrophe that supposedly shrunk the, the human population, is that when you look back in the genetic record of people, you don't see this population collapse quite at the same moment as we know that the, the volcanic eruption happened. Because that ash, it left a mark in the geological record. You can see exactly how far. And we see dust all the way over to East Africa, right? So it's kind of enormous spread from Indonesia to East Africa. But what you can do is you can take people from around the world,

• 16:25Hannah Fry?

  and you can look in their, in their genes, and you can basically ask yourself the question, if I walk backwards in time, how far do I have to go before two randomly selected people have a common ancestor? Before their genes demonstrate that they have a, a common ancestor? And by doing that, and doing that repeatedly with people all across the earth, and then looking backwards and backwards and backwards further in time, you can see that there were definitely moments where the population of humans really shrunk. Not as much as leopards, by the way. Do you know this about leopards?

• 16:56Michael Stevens?

  No, what happened to leopards and when?

• 16:58Hannah Fry?

  Leopards is like the best example of population bottlenecks. Leopards are so genetically similar to one another that you can take a skin graft from any leopard you like and pop it on to another, another leopard, and it will not be rejected.

• 17:12Michael Stevens?

  Do we know when? This bottleneck happened.

• 17:15Hannah Fry?

  Yes, we do. And we know, we know how small the population got as well. Just, just on that point, though, that idea that a leopard can't change its spots turns out not to be true. You can just borrow them from another leopard.

• 17:27Michael Stevens?

  My goodness.

• 17:28Hannah Fry?

  The, we know it was about 10,000 years ago. You can tell this in the genes. And they reckon that something happened that meant the population of leopards went down to about seven.

• 17:38Michael Stevens?

  Seven?

• 17:39Hannah Fry?

  Right? There are seven common ancestors around about that among all leopards. And it's only 10,000 years ago that that happened. Now, in humans, you can do the same thing. You can see there's these moments of decline. But there isn't one that directly lines up with the moment that the Topa super explosion, super, super eruption.

• 17:58Michael Stevens?

  Yeah, and that's disappointing for our quest today.

• 18:02Hannah Fry?

  It is.

• 18:02Michael Stevens?

  Also, when did these human bottlenecks potentially happen?

• 18:07Hannah Fry?

  There are plenty. There are plenty over, over, I mean, hundreds of thousands of years, right? So if you're going back 300,000, half a million years ago, you know, then you might be looking at populations that are, that are much more manageable in terms of as far as Santa is concerned.

• 18:23Michael Stevens?

  Great. However, I think we're now entering the territory where we need to define what we mean by person. Because if you go back 500,000 years, I don't think there are any Homo sapiens. There are, there's Homo erectus.

• 18:38Hannah Fry?

  Yeah.

• 18:39Michael Stevens?

  But as far as we know, and we're getting into really speculative territory here, Homo sapiens with the anatomical features that we have today, you and I and everyone listening, that didn't emerge until like 300 to 200,000 years ago.

• 18:56Hannah Fry?

  And this specifically is big brain, small jaw, upright.

• 19:00Michael Stevens?

  Yeah, the brain is like above the eyes, not just right behind it. Like a very, a very small skeleton. In fact, I love this theory that human intellectual abilities came about because we evolved such slight, dainty skeletons that cooperating together was our best bet, that we needed to plan ahead and assign roles and invent rules and morality because we couldn't just go out there, grab an animal and kill it on our own. We didn't have claws. We didn't have big teeth. So we had to. Design tools and work together.

• 19:34Hannah Fry?

  Because these are the two things that set us apart from any other species is that we're cognitive and we're social.

• 19:40Michael Stevens?

  That's right.

• 19:40Hannah Fry?

  Yeah, okay, so 300,000 years ago, we're talking, but even then, I think that the population of Homo sapiens then was like, we're still talking pretty small, tens of thousands, maybe hundreds of thousands.

• 19:51Michael Stevens?

  I know. And here's another problem. When we look at the evidence we have, like the oldest Homo sapien fossils ever found, that's not like, oh, guess what, guys, all the humans alive on Earth used to live in this like one cave. They spread, like spreading out was just like their thing. We've got ancient, ancient, oldest Homo sapien fossils found in Ethiopia and Morocco. And you cannot travel that distance on a reindeer in a night.

• 20:23Hannah Fry?

  I've got a few options. There's, of course, there's elephant birds. These are, you would find these in Madagascar, not far away from the cradle of humanity.

• 20:34Michael Stevens?

  Are they extinct now?

• 20:35Hannah Fry?

  They are extinct now. They were 10 feet tall, they 200 kilograms, they were around until about 1,000 years ago or so. Couldn't fly technically, but still, they're elephant birds. I mean, what more do you want?

• 20:48Michael Stevens?

  And they were big enough you could ride them, and I guess they were probably pretty fast. Okay, so you had means of transportation to like, go quite a distance.

• 20:56Hannah Fry?

  You could. I mean, there's also, there's the giant ground sloth. That's another option that was around 5,000 years ago.

• 21:03Michael Stevens?

  Where do they live?

• 21:05Hannah Fry?

  You find them in North and South America, so quite far away, but.

• 21:08Michael Stevens?

  I think we should allow this prehistoric, non-magical human to like, travel, bring a giant sloth over to where the actual Homo sapiens are. They can prepare.

• 21:18Hannah Fry?

  We're bending the rules ever so slightly here.

• 21:21Michael Stevens?

  Yes.

• 21:22Hannah Fry?

  Well, on that note, should we go for a break?

• 21:32Speaker 04

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• 22:39Michael Stevens?

  All right, we'll come back. I just went on the record saying that in the year 275,000 BCE, a person could have done what Santa does by themselves. That humans may have been close enough together and small enough in number that you could have visited every single one of them in one night. However, that's like so speculative. I mean, we don't know enough about human evolution to say that there weren't some, I don't know, some human ancestors that had already migrated into Asia and then they like evolved cognitively and anatomically in the same way thousands of miles away from those in Africa. It's, we just don't know, but look.

• 23:16Hannah Fry?

  Don't caveat this. What are you doing?

• 23:18Michael Stevens?

  I'm caveating because there are so many.

• 23:22Michael Stevens?

  Theories and there's so many unknowns and I think it's actually really exciting that we we still have these questions to answer. Ultimately, I just love knowing that like it may have never been possible to visit everyone in one night.

• 23:35Hannah Fry?

  I'm still I'm still stuck on how geographically spread out they were because I think if you're talking hunter-gatherer situations here, you're probably talking about sort of family pods of 10 to 20 that will probably have their own territory, sort of geographically distinct from one another. So I think even if you are on an elephant bird or a giant sloth or whatever it might be, I think getting around all of them. Also, actually, you know, early humans, Homo sapiens, Homo erectus, whatever it might be, were nomadic. So you couldn't even have like a map of where they were and be able to go and find them in the same place. You know, these people were moving around all of the time. So I think you would have found people, even in the earliest days, spread out across the

• 24:20Hannah Fry?

  entire continent of Africa.

• 24:22Michael Stevens?

  I think I think you're probably right. I don't think that, again, it's not like a couple chimpanzees gave birth to a Homo sapien and they were like, what? And then you were like, oh, cool, I've only got one gift to give out tonight. We're talking about like ape species like Homo heidelbergensis and Homo rhodizensis, who slowly became more anatomically like modern humans. And they didn't necessarily do it all in the same city, all in the same camp.

• 24:51Hannah Fry?

  There's also Neanderthals that feed into this. I mean, Neanderthals are sort of in the Middle East at this point while while the Homo sapiens are in Africa. Every human has about 2% of Neanderthal DNA, but only if you have non-African ancestry. And it's because the Neanderthals were in Europe, they were in the Middle East, and as Homo sapiens came up through Africa and then sort of went off to the rest of the world. That's where they interacted with Neanderthals. Neanderthals didn't go down into Africa.

• 25:23Michael Stevens?

  For this to work, for A person to visit every Homo sapien, they've got to do it before Homo sapiens.

• 25:29Hannah Fry?

  Leave.

• 25:30Michael Stevens?

  Leave, before they're in Eurasia or beyond, because you just can't cover that distance in a night.

• 25:36Hannah Fry?

  They reckon it wasn't very many who left, you know. In fact, if you take somebody, if you take someone from China, from modern China, and you take someone from, I don't know, Europe, South America, basically anywhere else in the world. Take two people from around the world, not Africa, and compare their genetic codes, they will be more similar than if you take two random people from Africa and do the same thing.

• 26:02Michael Stevens?

  Wow.

• 26:02Hannah Fry?

  Because really, a small number of Homo sapiens left, and all the rest of us are descended from that small number. Whereas in Africa, where humanity started, where Homo sapiens came to be, there are so many distinct pockets of genetic groups that there is so much more variation within Africa than without it.

• 26:24Michael Stevens?

  That's incredible.

• 26:25Hannah Fry?

  Hmm. So maybe, maybe you could just be Santa, standing at the sort of edge of Africa, through, through the Middle East, being like, handing people out their Lego as they go past.

• 26:35Michael Stevens?

  Maybe that's what happened. Maybe that's why they all left. They were like, guys, someone's giving out free pinches of red ochre. We've just got to go up north.

• 26:44Hannah Fry?

  Free beads. Shall we talk about the types of gifts that actually would have, would have been handed out in 275,000 B.C.?

• 26:50Michael Stevens?

  Well, yeah, I mean, I, I've said, like, I kept thinking that it's going to be like a bead. It needs to be something small, because you've got to carry around a lot of them.

• 26:58Hannah Fry?

  Yeah. I think there is quite a lot of evidence that beads were given as gifts, like, a very long time ago, maybe not quite 275,000 years ago, but definitely far back in time. Because for a really long, long time, we sort of thought that symbolic art started in Europe, with sort of, you know, 40,000 years ago is the earliest evidence of, of kind of cave paintings, that sort of thing. But actually, there is a discovery that was made in Bismun Cave in Morocco. This is maybe a hundred and forty thousand, a hundred and fifty thousand years ago. And are these tiny little sea snail shells that have got little holes through them as though they were strung through something, so sort of like as a necklace. Basically, they were used as beads.

• 27:39Hannah Fry?

  And you can be certain that the shells didn't just wash up there because they were found way too far inland, sort of hundreds of kilometers. And they also showed these microscopic wear patterns around this hole, kind of proving that they've been strung on this cord and they've been jangled together. And the idea is that these were sort of given as status symbols. So they must have been traded because they just had travelled too far a distance. Must have been traded and gifted. And yeah, the idea is that they would signify who you were, whether you were married, whether you were not. You know, your status within the hierarchy, that kind of thing. So that would have made quite a good gift, a beaded necklace.

• 28:19Michael Stevens?

  Yeah, and it wouldn't have weighed a lot. So even if there were hundreds of people that you wanted to give them to, you could carry them all on your cheetah or giant ground sloth.

• 28:29Hannah Fry?

  Yeah. One of, I think, another good thing that you could give that would make prehistoric man slash woman extremely happy would be a miniature hand axe. Do you know about the archaeologists that found these? These are absolutely amazing. So in particular, in Wolvercote, this is in the UK, archaeologists have found these axes and they are absolutely tiny. They're like this big, right? Five to seven centimeters, basically the size of a matchbox. And they are like perfectly made. They're perfectly symmetrical. It's not like they're sort of, you know, were big axes that got shrunk down. They were deliberately made to be that size.

• 29:10Hannah Fry?

  And, you know, they've been natural, like this absolute perfect level of precision. They're also totally useless, right?

• 29:17Michael Stevens?

  I was gonna ask, yeah.

• 29:19Hannah Fry?

  Completely, I mean, if you're thinking about sort of butchering mammoths and chopping wood, I mean, this thing is not doing anything at all. So in 1999, there's these archaeologists, Merrick Cohn and Stephen Mithin, and they proposed the sexy hand axe theory.

• 29:34Michael Stevens?

  Is this the idea that it was done to show your skill and your ability as a craftsman?

• 29:39Hannah Fry?

  Sexy hands, exactly right. Exactly right.

• 29:43Michael Stevens?

  And isn't that really what gift giving is all about? Showing how good you are as a gift giver? Aren't I thoughtful? Aren't I skilled? I didn't buy you a cake, I made you a cake because I'm skilled. It shows your worth and your value. So when are these miniature hand axes from?

• 30:00Hannah Fry?

  We're talking a long time ago, like 300,000 years ago, maybe even older.

• 30:05Michael Stevens?

  Wow. Okay, so that shows that appreciating gifts is very old. Appreciating skill.

• 30:14Hannah Fry?

  What's the best gift that you've ever given, Michael?

• 30:17Michael Stevens?

  Uh, the gift of life to my daughter.

• 30:20Hannah Fry?

  Ah, great answer. Great answer.

• 30:24Michael Stevens?

  I've given a lot of bad gifts. When I was just dating my now wife, I thought she really liked mechanical pencils. She talked about how she liked them a lot. So I got her like really nice mechanical pencils, right? Like fancy ones and she was not amused.

• 30:40Hannah Fry?

  I think that's because you and I are stationary pervs and clearly, clearly she is not.

• 30:45Michael Stevens?

  Well, yeah, I think she just needed a mechanical pencil to do drawings on patterns. And then I'm sitting here like, oh yeah, well, what if I got you this special two-stage pencil sharpener? And da, da, da. And she's like, no, no, no, no, no, no. I don't like them in that way.

• 30:59Hannah Fry?

  Tell you what you could do for your, for your special prehistoric Santa.

• 31:04Michael Stevens?

  What?

• 31:05Hannah Fry?

  Maybe you can't leave out some mince pies. There's little metal trays that they come in. That's not a thing yet. But alcohol is, alcohol absolutely still is a thing, even as far back as 275,000 years ago. And we know this because, well, for one thing, fruit, if it is left to ripen for too long, becomes alcoholic essentially.

• 31:28Michael Stevens?

  It just happens, right?

• 31:29Hannah Fry?

  It just happens, right? 1% to 4% ethanol you can find in fruits, just as they are left to ripen. And other apes, other monkeys will happily consume fermented fruit in order to get very drunk. You also get elephants sometimes doing this, breaking into breweries. That's something that occasionally happens. Basically, animals love getting drunk. It's a, it's a thing. Also, humans, the clue that we have prized alcohol for a very long time is that we are amazingly good at detecting it. We can detect even the slightest little whiff of something being alcoholic, which, I mean frankly, that beer radar came from somewhere. There's also the theory, do you know about this?

• 32:12Hannah Fry?

  The theory that actually we we ended up going through the agricultural revolution, not because of bread, but actually because of beer.

• 32:22Michael Stevens?

  Because of beer?

• 32:23Hannah Fry?

  The beer before bread theory.

• 32:25Michael Stevens?

  I'll buy that. I mean, it didn't it didn't affect all humans, obviously. But those that decided, yeah, you know what? Let's be agriculturalists. Maybe they did it for the beer.

• 32:35Hannah Fry?

  Because here's the idea is that actually bread, to make bread, it's a lot of faff to make bread, right? You've got to grow the grain, you've got to grind it down, you've got to, you know, bake the, bind the yeast, whatever, you've got to, there's a lot of effort. And then what you're left with is not even that calorie dense. Sort of actually something that you could replace quite easily with something that you you foraged or something that you killed. Whereas beer, on the other hand, I mean, that sort of feels like it's worth it. It's sort of more, you know, you've got your your social cohesion that comes with it. You've got, it's a safe form of hydration.

• 33:09Michael Stevens?

  Right.

• 33:09Hannah Fry?

  This sort of kills all the bacteria in the in the liquid. There's also, one of the clues is that when you look in the archaeology of when domesticated grains, so to speak, when grains that have clearly been bred in order to be used for agriculture, when they start to appear, they they start to appear in places like temples rather than in in kind of ancient households. So this is this, I mean, it's not completely, like you said, right? Everything under the sun here is is very much, we've got lots of question marks all over the place, but it's quite possible that that people knew how to make beer or beer of some form that you could then give out to your prehistoric Santa.

• 33:54Michael Stevens?

  Yeah, great, great. Merry Christmas.

• 33:56Hannah Fry?

  Merry Christmas indeed.

• 33:58Michael Stevens?

  And they're drinking my little prehistoric beer, being like, who's Christ? And I'm like, ah, you guys, just wait 275,000 years, this will all make sense.

• 34:07Hannah Fry?

  Yeah, and you would not believe the conversation we have about you in 277,000 years' time.

• 34:13Michael Stevens?

  Yeah. Hannah, this was a lot more difficult than I thought and a lot less clear. I just think that we don't have enough evidence to know if Homo sapiens were ever concentrated in a small enough place to all be visited in one night.

• 34:34Hannah Fry?

  I just don't think they were. I just don't think they were. I'm going with no. I'm going with it's not possible.

• 34:39Michael Stevens?

  I know. I mean, if they were, it would have been like 200 to 300,000 years ago. And then you could have played out your little Santa fantasy for real without needing any kind of magic or any kind of cheats. But gosh, that's kind of what makes the whole story of Santa so special.

• 35:00Hannah Fry?

  Yeah, I mean, you've basically got two options. Option one is don't worry about geography at all. Just deliver a gift voucher by email to all 8 billion people simultaneously. That is available to you. You can do it now. Just get everyone's email address. Not sure how you do that. Not sure everyone has an email address. Whatever, details. But you could do it right now or sit back and let the big man himself take over.

• 35:23Michael Stevens?

  Yeah.

• 35:24Hannah Fry?

  He's the one with the leaky bones. He's the one with all the millennia of experience. And I think we'll leave it to him, shall we?

• 35:31Michael Stevens?

  Cheers.

• 35:32Hannah Fry?

  Well, that is all we have time for today on The Rest is Science. As ever, you can email us, [email protected].

• 35:41Michael Stevens?

  Or join our newsletter at therestis.com/science.