Tea: The Splendid Elixir, Part 1

Published Feb 2, 2023, 6:20 PM

In this series from Stuff to Blow Your Mind, Robert and Joe discuss the history, mythology, culture and nature of tea. So start a kettle and prepare to listen with your favorite cup… 

The first cup caresses my dry lips and throat. The second shatters the walls of my lonely sadness. The third searches the dry rivulets of my soul to find the stories of five thousand scrolls. With the fourth, the pain of life's grievances evaporates through my pores. The fifth relaxes my muscles and bones become light. With the sixth, I find the path that leads to the immortal ancestors. Oh, the seventh cup, better not take it. If I had it. The only feeling as the fresh wind blowing through my wings as I make my way to pung Lie. Welcome to Stuff to Blow Your Mind production of My Heart Radio. Hey you, welcome to Stuff to Blow your Mind. My name is Robert Lamb, and I'm Joe McCormick. And today we're going to begin a series on t Yes, t the beverage and the plant that it comes from. Now, Rob, you began today's episode by reading a uh, is this a poem or a song? This is a poem by Lu Tong from the Tang dynasty titled Seven Bowls of Tea, and it's it's pretty widely cited. I I ran across various like tea blogs talking about and sometimes saying that this is overly cited in the literature of tea, uh you know, especially in the West. Um and I think with good reason because it's it's amazing, it's a It captures this just intense enthusiasm for tea. And also it's essentially about a man drinking way too much tea during the course of the day that brings him to the to the very brink of like blinking out of physical reality and going to uh uh to ping lie the mystical mountain where you have fantastic creatures and immortal beings. So you don't want to do the Seventh Cup because that will just essentially you will leave your body in the place where you currently reside. Right. But it's not, it doesn't seem to be a case where you have to worry about like crashing with that seventh Cup. It's just the seventh Cup is one pleasure beyond that which you should grant yourself. You should you have to show restraint because you still have stuff to do here in the mortal realm. Well, I like the way that the poem escalates because at the beginning it's more just about the uh. Like the first line is about the sensory experience caresses dry lips and throat. It's it's happening in the mouth. And then after that it's like mood, you know, shatters the walls of my lonely sadness. That's mood stuff. That's level two. But beyond that, you're like talking about communing with other beings, the path that leads to the immortal ancestors. Yeah, it gets very spiritual towards the end, transformative. Even I've never gone six cups in on caffe aated t, but I don't doubt it. Yeah, I, um, my wife and I probably have, but only through re steeps. We're big into um having a picking out a good tea that you can resteep several times. So um, I could probably write a similar poem about, like, you know, steeps one, one through four or five on a particular tea that I like, because sometimes you get to get the you get an interesting tea and it changes like cup Cup one might actually not be the best cup. It's your second or third steep where things maybe become a little more nuanced, a little less sharp. I found I found that to be the case with some of the poor teas that I really like. I assume just the caffeine content become less powerful as as you go through multiple steeps. That is my understanding, and I believe that is my experience. Uh, and that's one of the reasons I tell myself that it's okay to have so many cups of tea during the course of an afternoon because I'm getting decres east returns on on that cup from a caffeine standpoint. But yeah, we've touched on tea in the past, we've, but we I don't think we've ever done a proper deep dive on this most splendid beverage US and not just splendid, but really one of the most popular beverages in the world. You could probably make a case for it being the most popular. Uh. There's a great deal of variety to how it's cultivated, prepared, brood and consumed. And yeah, there's no denying its appeal um, and it's importance weaves in and out of global history, various cultures that factors into mythology, literature, politics, and much much more. Yes, And to clarify something here, I guess we should do this at the beginning. Uh, there's a little bit of confusion in English. I don't know if it's like this in other languages, but at least in English, there are a lot of things that we call t that are not made with the T plant. So we use the word tea as like a generic synonym basically for an infusion. Anytime you you take a substance, herbal or otherwise, you expose it to hot water in order to extract some kind of flavor or chemical compounds into the water, and then you drink the water. People will call this a tea no matter what it is. So you've got herbal teas made from everything from like camera meal, to turmeric to mint, or even cases where people will will refer to meat based broths as like beef tea, but there is no really, But there is also the specific tea plant, uh, the leaves of which are used to make tea proper. And it is this plant and it's eponymous infusion that we're going to be mostly focusing on in these episodes. And obviously there are various blends that have taken place. There's so many teas available now, especially loose leaf teas where you'll have like little bits of dried um um flavor bits that are not tea, but still the primary ingredient is the dried tea. Now, I think one of the other exciting things about this is and this is gonna be a fun one to hear from listeners because I know everyone out there you have your own individual story with tea. You probably have your own cultural story with te um. For my own part, I've come to like a number of different teas. I want to also throw out an important caveat that I would not say that I'm like a t super nerd. You know, I'm not like I'm not a connoisseur of tease, so I'm not going to be speaking from that vantage point in these episodes. But I've grown particularly fond of these poor ties, which will discuss in due course. UM. I like several things about them. I obviously I like the various tastes. They often have this kind of dark earthy or sometimes there's lighter but something There's often an earthy tone to them um sometimes compared to hey and and that is a flavor profile that I find it works. You get interesting results when you do re steeps on it, because the hay taste might be a bit strong in that first cup, but then cup two or three is generally the comfort zone for me personally. I also really love how so many of these particular teas are preserved in bricks or pucks. Sometimes you have to break up the brick with a little a little specialized knife, and I like the ritual of that. I also like it when it's a little puck that's already been prepared, often uh circular, sometimes heart shaped uh today and that can be a lot of fun as well, and also makes it a little handy easy to get into the tea bag. Rob, I seem to recall you getting very into the idea of, uh, some kind of disgusting nineteenth century way of preparing coffee that involved like brick or puck based concentrate, and I am I remembering that right. Oh no, no, no, I think I was interested in the study of like Civil War era instant coffee, but none of it sounded like anything I wanted to even experiment with. Okay, no, no, no, I just meant that you were interested in the idea, and not that like you talking it's virtues as great coffee. No, no, it's just it's interesting history, like and It kind of speaks to the importance of of caffeinated beverages to the people who consume them. Uh, you'll have situal like war situations where people realize, Hey, these soldiers need coffee, these soldiers need tea. How do we get that to them? What is the most cost effective means of doing so? What happens when the product is bad? How do the soldiers in the field relate to this additional indignity. I also love how tea is like anything else. Uh, there's nothing like great branding. I love some of the names of the teas that I have enjoyed, Like there's one called the Bewitched Emperor, there's one called Evil Snake King, and so yeah, I'm I'm obviously these are just just the labels given to these and these are the English I think these are translations though of what they're actually called in in the case of these two in China as well. But I just love the idea that is wrapped up in the branding for these as well. It makes me feel like I'm I'm not only enjoying an afternoon up with tea, but I'm engaging in something possibly supernatural. M Well, I would say that I sense no other beverage to have as rich an array of supernatural associations as tea. Yeah, I think so, Like there's just there's there's so and it's one of the things that's interesting but also could probably be intimidating at times as you get into not just ta culture, but various tea cultures that all have various practices of uh, how you're supposed to prepare it, how you're supposed to consume it, and so forth. I mean Macha from Japan is of course a great example of this um and uh and just on its own can be a wonderful tea. Uh. Yeah. There there's just so many, so many fascinating teas out there. We're going to touch on some of the tea cultures as we proceed through these episodes. But but how about you, Joe, what's your your personal story with tea? Well, I am not really a t drinker, not because I dislike tea. I mean, and when I have it, I enjoy it. But I think it's because for me personally, there is simply not room for additional caffeine in my life. I have my my morning coffee routine, and I have to be very careful even with that, because if I have too much coffee, I will spend the rest of the day and night having visions of the doom of all and just hear the screams of a dying planet like I get the fear bad. And it's strange. I wasn't always like that. I can think years back, I used to hang out with my friends and drink cup after cup of coffee and I was fine. Something happened to me, and now I cannot handle that much caffeine. It just res me. So after I've had my daily coffee, I do not have tolerance for anything else. No no tea proper, no no second or third cup whatever. Uh So, in order to do caffeine eated tea, I think I would have to do a full switch out and have it instead of coffee, which I've never tried to do. But occasionally I do enjoy non tea teas. I like some herbal teas, lemon ginger and fusions and stuff, and I guess they do make decaffeated tea, but I've just never gone down that path. M hmm. Yeah, yeah, I'm like you, and that I can't quite put aside the morning coffee I've gotten it down to just two cups of coffee, my initial wake up cup, and then the second cup of coffee, and then everything after that for me is key. Generally it's one tea bag, multiple steeps of set tea bag. And it's worth keeping in mind when thinking about the caffeine. Now, this is just general, and this is maybe maybe can't be applied completely across the board, but generally speaking, a cup of coffee, standard cup of coffee is gonna have somewhere between a hundred and hundred twenty milligrams of caffeine. Meanwhile, a cup of black tea is gonna have forty milligrams of caffeine. Green tea's gonna have thirty. Green and white tend to have the least amount of caffeine, followed by oolong. These numbers are pointed out by Laura C. Martin, whose excellent book A History of Tea is one of the sources I'm gonna keep coming back to in these episodes. Okay, so even if I did try to incorporate uh some tea into my daily routine, it would not be equivalent to drinking the same volume of coffee. Yes, that that seems to be the case. Now that that being said, there are so many ways to prepare tea, and certainly you could drink enough tea, you could drink those six fresh steeps of tea and risk transporting yourself to the mystic mountains. So it's always always possibility, and everybody's different, and you know, and and I think our relationship with Katheine does change as we age, so naturally, yeah, you don't have to be a total tea nerd or immerged to any degree within an Eastern culture of tea to be into TV, because tea has spread around the globe by this point. Tea culture now encompasses everything from British high tea to Southern sweet iced tea uh Taiwanese bubble tea to things like Senegalese um tea and they're you know, they're Tibetan um uh tea preparation methods that are also rather distinct, and again we'll come back to some examples of these later on. But I thought an interesting place to start might be too. Instead of starting with the familiar or even anything in the actual real world, we might start off by getting into the mythological origins of tea even before we get into the botanical realities of tea, we might start and just purely mythic and I think mostly Chinese mythological origins for this splendid beverage. Oh wait a minute, Wait a minute. If we're getting into a myth about a psychoactive substance and its ancient Chinese myth, are we going to meet the divine farmer once again? Yes, yes we will, because of course, if it involves something that you should eat or shouldn't eat, and is a plan of some sort, then yeah, the divine farmer Shinnong has to show up Shinnong putting things in his mouth for everybody's benefit. That's right. Yes, we've We've talked about Chinong before on the show. He's a pretty important figure in Chinese mythology and he's tied to myths concerning various botanical substances. Um. His name literally means divine farmer. He's a culture bear, a god um. He's attributed with the invention of agriculture and the introduction of agriculture to human beings. Uh. He's an important name in Chinese medicine. He's said to have invented various farm tools and musical instruments. Uh, So there's a lot that this mytholological figure is attributed with. And you know, obviously as a mythological figure, he is sort of summing up and condensing a lot of the things that actual human beings did over the course of generations. Figuring out which plant has a medicinal property or seems to which plant is good to eat, which plant will kill you, that sort of thing. You should definitely look up some images of him because he's He's often depicted as this kind of squat older man with bovine or ox like characteristic, often kind of wide set eyes and and even one of my favorite things about him is he often has these kind of nub like horns. Now I have seen depictions I think these are more modern, but it could be wrong where he has like full blown horns, like like a hornet deity. But generally it's these kind of nubs where he looks just again, very very bovine. Would you call him buds? Are those called buds? Yeah? They kind of look like like buds. Yeah. Like, if you don't know what you're looking at, you might say, well, well, why does that man have two bumps on his head? Uh? And it's because it's invoking this kind of ox like characteristics, Uh, characteristic of the character. And in some tales he was said to have had the head of a dragon, others the head of an ox. And so we do have to remember that he is a god, of course, so it's natural that he might have some qualities like this. There are various tales about his birth, including some traditions that relate his incredible rate of maturity. Uh. Once version said that he to talk at three days old, he had all of his teeth, etcetera. And in some accounts his father was an actual dragon. Wait when you said had all of his teeth, he meant he was like born with all of his teeth, or he had all of his teeth when he was three days old. His memory serves, and I believe this is related in the book Chinese Mythology by yang On and Turner. Uh, there's tales it's like, all right, at three days he had this, At four days he had this. So he's just maturing at a rapid rate, where at like three months old, he knows everything about agriculture and he's able to teach it to humanity. Okay, but the basic story with Shinnong concerning plants is that he not only gave humans the knowledge of agriculture, he also sussed out which plants were useful in medicine and which ones were food, and also which ones were poison. And he did this, of course, by testing them all himself. Uh. In some tellings, he's not actually eating them. He's thrashing them with a reddish brown whip, like a whip that is um. And there's a lot you can get into with the symbolism of it. I've seen that it's there's something to it that this is kind of the color of dried blood. Um. Other times he has a cauldron. Uh so yeah. In some cases he says to have, you know, some tools that he's using. But in many tellings and certainly many artistic interpretations, he's testing all of these various botanicals out by eating them, and then afterwards he passes judgment. He's like, Okay, this this is a plant that would be good from medicine, so I'm going to put it into my right hand bag. Uh, this one is good for food, so it's going into my left hand bag. And he sorts it generally like that. What about the ones that are poisonous um. He there's one tale where if something's poisonous, he just wants to stop it. Like, I think there's a story that's related about Ginger where originally Ginger was said to be poisonous and she took a look at each he like he checked it out and he's like, yeah, this is horrible. I want to stomp on it as well. And then Ginger had to change in order to be accepted, and that's and Ginger went underground. Oh beautiful. Yeah, so yeah, I want to explore that one more at some point because I don't really understand all the meaning going on there, but it's it's it's interesting. Now. I don't know if we've talked about this version of the story with Schino before, but as yang On in Turner point out, in Chinese mythology, some versions also state that Shinong is particularly good at figuring all of this out because he has a crystal stomach and he can see everything that's going on inside of his own internal organs as he's digesting things. He's like tobor He's they open up his his stomach and they can look inside and see see all the parts working. Yeah. Yeah, I just I love, I definitely picture this is kind of like almost some sort of an android body that he has going on underneath his his robes here that he can pull it up and yeah, it's just crystal organs under crystal skin, and he can observe all every little detail going on in digestion. So in some versions of the story, the first plant he was said to taste was a green leaf, which once he put it in his mouth and swallowed it, it went on a grand tour of his insides, cleaning up everything along the way. And again, crystal stomach, so he gets to watch it go. Okay, so it's kind of like a dryer sheet or something. Yeah, yeah, I guess. Um. This particular plant was referred to as cha, which means to inspect, which eventually got confused in later tellings with cha, which is the exact same phonetic sound but a different Chinese character. So the story becomes later on that Chinong was poisoning himself upwards of seventy times a day, testing out the world's plants to determine which ones we could use for various purposes, and if something got on top of him, he got some poison going around in his system, he would turn to the cleansing power of tea to detoxify himself. Oh so, by the way, you should not derive actual use value for from that. But yeah, so in this version of the story, tea is like a universal antidote, right. And my understanding too is that older versions of the story are not referring to tea, but it becomes tea, and later tellings of the story. Uh, though though there is this eventually catches up with him. Um. I was reading in the in that book that one day he has said to have tried a yellow flower, and upon trying the yellow flower, it broke his intestines into pieces. So I guess he sees this through his stomach, his crystal stomach. Uh. This occurs the just the moment he swallows it, and he's quickly trying to, you know, get himself some tea so he can cleanse everything up, but it is too late. He dies, and the plant uh that that does this to him becomes known as the intestine breaking weed. That is brutal in so many ways, especially because it imagines the testines as brittle rather than elastic. I mean, I guess you could think of them that way. Uh, well again, it makes me personally think of Shinnong's crystal organs as being like glass. And then the shattering is kind of like when a cartoon character bites on on something that's too hard in their teeth. Do that that cartoon shattering thing? That's what I picture in my mind happening to Shino here portion on, Yeah, thank thank Now. There's a book, Shinnong's Herbal Classic, a later Han dynasty book that includes a great deal of knowledge related to various botanical substances, and this book is attributed to Shinno, likely based on oral traditions. It includes a passage on t telling us that it's bitter and share some details about when, how and where it grows best. But as Laura C. Martin points out in a History of Tea, references to tea in this book were probably not original to it, as the character for tea itself didn't come into usage until uh seventh century. But more on the timeline of T in a bit, because we're still for now in the mythic timeline. Okay, But talking about this book attributed to Sinong, the idea is that, uh, probably there were earlier versions of the book that did not have the tea passages, and then recopying through the year's tea passages were inserted by some editor or copyist exactly. Yes, Now there are a couple of other tea related myths here. This is one that young on In Turner point out. It's a creation myth of the the young ethnic people known outside of China as the Poloang people in your non province. And it said that in this creation myth, a hundred and two tea leaves went around and around in the air for thirty thousand years and then transformed into fifty one young men and fifty one young hmen. That's the beginning of humanity. Now there's another one. This is uh This is a tea myth that largely emerges from India rather than China. As Martin points out, the early history of tea centers around China, but the plant is indigenous to the Assam region of India in addition to southwestern China. Yet it seems that it was little known or used in India prior to the sixth century see heat and if you don't know where it is, a psalm is located in northeastern India, so the the area of origin for the tea plant we think is basically southwestern China northeastern India. Yeah yeah, though it does seem like it was better known in China as opposed to India. But of course we see a fair amount of cultural exchange between India and China, and of course the most famous example of this is of course Buddhism, and this particular story does involve Buddhism as well. It's the story of Bodhidharma, who was a fifth century semi legendary Indian prince who, much like the Buddha himself a thousand years earlier, came to see the emptiness of wealth and abandoned all of it in the quest for enlightenment. He became a Buddhist monk, and after many years of study, he travels to China to reintroduce Buddhism and found Buddhism had been introduced into China previously, but this most period where maybe he was waning a bit, and he said to end up becoming the founder of Chan Buddhism in the process. But while he's in China, after visiting the emperor on this trip, he retreats to a Shaolin temple and here he begins a long period of devoted meditation and asceticism. So depending on the tail, and again they're different versions with this says with most of these stories, he either stares at a wall for nine years in meditation or he gives up sweep for nine years so that he can really double down on his meditation. In version of this story, he grows so sleepy that he reaches out and he grabs a leaf, like a random leaf, and he just shoves it in his mouth to chew it as a way to perk himself up. And his luck would have it, this plant is tea, and it really does perk him up because it's we'll discussing a bit it it contains a stimulant. Uh. There's another version of this tale, and this one um I got in trouble for sharing at the dinner table in my post research excitement. But in this other version, he's getting sleepy and he pulls off his own eyelids because it's like heavy eyelids that keep shutting. I'm trying to meditate, but I keep falling asleep. So he just pulls the eyelids off, throws him on the ground, and then a tea plant grows from where where the eyelids fall. So in either case, according to these these this legendary account, he discovers tea and passes it on to the other monks to assist them in their meditation. All right, So that that's just a taste of some of the mythological stories and involving the origin of tea, this spectacular plant that is either discovered or or perhaps even created out of some sort of inspired inside by a legendary or semi legendary individual. Now, when it comes to the t plant itself, I uh, there were a few things that I actually did not know until recently. I don't know if I should be embarrassed about not knowing these, but I was just pretty much in the dark about tea. But one thing I discovered was that, apart from the issue of things being called t just actually being an infusion of anything, even when you're talking about the tea plant itself. I previously thought that the main varieties of tea you hear about, like green tea and black tea, or maybe oolong tea, were from different plants. But actually these are all from the same plant as far as I can tell, They're just different preparation and curing methods. Correct. Yeah, Yeah, they're essentially we're talking about one single species of plant. Camelias sinensis camilius and insus is an evergreen shrub or tree and uh, you know asterix there, we'll get to that that produces small, white petaled flowers. In the wild, it will eventually reach tree size, but in in situations where it's been cultivated, generally they're kept at a shrub size via pruning. Uh. They're typically kept at like a meter or three feet in height, as that's an ideal height for picking. Yeah, and so you have these top layers of leaves that come out and I think they refer to those as flushes, like the leaves keep uh protruding, and then the top young leaves are harvested. Yeah. And while we're essentially talking about one species, there are two varieties. There's Camillia sinensis. This is the one that's indigenous to western Yunahan and China. And then there's a variety of that Camillia sinensis assamica. This is indigenous to the Assam region of India as well as parts of Myanmar Island, Laos, Cambodia, Vietnam, and southern China. Now, these two varieties, they cross pollinate easily, so they're also blends of the two, but Martin stresses that they're they're actually not that different in taste either. So the varying tastes and colors of different teas they stem from the way we process them, whether you're talking about black or green or along, et cetera. And so either variety of tea leaf process the same way will basically be similar. But at the same time, we don't want to discount traditions surrounding particular teas. Um. It's one of those things. It's kind of like, you know, wine taste or any kind of like uh, cultural food tradition. There's a lot tied up in knowing where something comes from as well, and some of that trans translates into the into the taste for the average consumer. Sometimes it's something that translates into the the connoisseur's taste experience. And sometimes you're getting into an area where yes, you're being primed that this uh, this particular I don't know, um uh you know that this wine stems from this vintage versus this vintage, this winery versus this winery etcetera. Yeah, yeah, I mean, I think there are a lot of different foods that maybe you actually couldn't tell the difference in in a blind taste test. But then again, it might be cool to enjoy an authentic version of something knowing the history behind it, like knowing where it comes from and being able to think about that and so forth. Exactly so. In the wild, tea plants are generally going to thrive in an open woodland area or on the edge of the woodlands where they can benefit from the shade of larger trees. As such, when cultivating tea plants, they're generally grown alongside shade trees. Uh. These, as Martin points out, not only provide shade, but also, uh it keeps weeds away and enriches the soil. And uh generally the leaves and the buds are or what are harvested fresh leaves generally contain about four percent caffeine. I'm reading, And I was wondering about this because I had read that, uh it is maybe we can get more into this when we do some of the cultural history. But I had read that tea leaves were traditionally treated as a food plant in China. More so than a beverage plant and the beverage uh stage came later. And so apparently you can eat tea leaves like you can just prepare them like a green and chew them up and eat them. People do this sometimes and it's fine, though you need to be careful about how much you eat, obviously, because you don't want to overdose yourself on caffeine right right, because most of us don't have crystal clear guts that we can look at and and determine what's happening. Um, you know, by the moment. But yeah, that'll be fun to get into and subsequent episode. Um. The the history of tea as a beverage is also the history of a food. Uh so, yeah, I'm looking forward to that. But coming back to the caffeine, this is a question that applies of course to tea, but also to other caffeine eated beverages or at least ones that have a natural origin, Like why is there a caffeine in the leaf? Like what? What is there? Why? Why is that substance that that for us humans as a stimulant that kind of manipulates us as a consumer of the plant, Like why is it even there to begin with great question. So as a jumping off point to answer this, I wanted to refer to an article I was reading on the subject by previous show guest Carl Zimmer, who is one of our favorite science writers. He's he's been a guest on the podcast before. Maybe we'll get him back again someday. But he came on to talk about his book on jeans and heredity called She Has Her Mother's Laugh, which is a fantastic book. And so Carl Zimmer had an article in The New York Times called how Caffeine evolved to help plants survive and help people wake up? And he begins by pointing out some rough stats about the popularity and power of coffee and caffeine, saying the world consumes roughly twenty six thousand cups of coffee per second. That's a lot. That caffeine is probably the most widely used psychoactive substance in the world. But there's an interesting thing about caffeine, which is that it has a number of different associated plants that it comes from. So, for example, there are coffee beans. Coffee beans are the seeds of a genus of flowering plant called Caffea or coffee a in the family ruby Ashi. These plants are native to tropical Africa and tropical Asia. There is, of course t tea again is made from the leaves of the evergreen shrub Camelius and insis, which is native to East Asia. There's mate made from the yurba mate plant, which is a holly shrub native to South America. Scientific name Ilex paraguari insis and and you've even got chocolate. Chocolate also contains caffeine. Chocolate is made from seeds of the cacao tree or theobroma cacao. Theobroma, by the way, means food of the gods, theo roma uh and historically was not always used as an ingredient in sweets and desserts. The main way we in the United States consume it today. It was often consumed as a bitter, hot, or cold beverage, kind of similar to how we consume coffee, which of course would have carried a punch of caffeine, and chocolate does have caffeine. I think our Invention episode where we talked to Jeff Beach Bonberri, we talked a little bit about ancient recipes for hot chocolate essentially, but It's kind of interesting to look at this geographic distribution and say, how do all of these different plants that are not closely related to one another independently make this same compound. We know why humans like caffeine, but what does caffeine do for the plants and how did all these diverse different species evolved to make it well. This article looks at a study published in the journal Science in where researchers detailed an effort to sequence the genome of a species of coffee plant responsible for many of the world's coffee beans. This remember, coffee comes from the genus Caffea or coffea, and this is a coffee a Caniphora. The study is by uh France um Oh. I do not know how to pronounce this last name d E n O e U d is how the name is spelled at all. And the title is the coffee genome provides insight into the convergent evolution of caffeine biosynthesis. Again, that's in the journal Science. So one thing this study looked at is how caffeine is actually synthesized in coffee plants, and it turns out it is a multi stage transformation of molecule that it begins with a compound called xant zine, and the coffee plan it manufactures several enzymes that act on this compound. So one enzyme removes an arm of the molecule, another enzyme adds a new arm. Two more enzymes come in and add two more clusters of atoms, and after all these transformations, you finally have transformed xantha zine into caffeine. And the enzymes involved in this multi step transformation are called in methyl transferraces. They are found in all plants and they do generally this sort of work, building specific compounds, many of which plants use to defend themselves against predators or parasites. And one example of a compound manufactured with the help of in methyl transferraces that Zimmer sites in the article is salacilic acid, which is a compound produced by willow trees which actually turns out to be a potent pain reliever in animals like us. Salacilic acid is the chemical basis for aspirin. But what about the enzymes that manufacture caffeine, specifically in coffee. Well, the authors determined that some time ago in the evolution of the coffee plant, a gene for creating one type of in methyl transfer ace enzyme underwent a series of mutations to produce a variety of enzymes which would eventually create caffeine. And so one of the co authors is quoted in Carl Zimmer's articles. This is by Victor A. Albert saying, they're all descendants of a common ancestor enzyme that started screwing around with zanta zine compounds. So the plants are just kind of like doing all these little variations on this originator molecule and producing these derivative molecules that in many cases are physiologically active or psychoactive on animals. And it turns out scientists had already discovered that caffeine was created by the action of in methyl transfer aces in cocaw trees and in the t plant, so similar molecular frameworks are going on within coffee plants with in within the tree that makes chocolate or cocao, and within ta plants. However, the researchers also found that the enzymes for for making caffeine in these different plants did not evolve from the same ancestors, so this would be a case of convergent evolution. Different branches on the tree of life evolving the same solution, the same phenotype independently. Uh So you can think of a million different examples of this. One is wings. Birds and bees both evolved flapping wings independently for flight. They didn't get them from a common ancestor that had wings. They you know, their last common ancestor did not have wings, and they independently, separately came up with the same solution. Now, when you see convergent evolution, when you see different streams of evolution converging on the same trait or the same solution to an environmental problem, it's usually a sign that that trait or solution is pretty good. It's a powerful adaptation and there's a big survival reproduction payoff. So it would seem, based on the evidence of convergent evolution, that producing caffeine is definitely good for something for the plants. So what is it really good for. Well, there are a few things we can talk about. One is activity in poisoning or deterring predation by insects. So, like so many of the plant based compounds that humans ingest on purpose for their psychoactive properties, caffeine seems to be at least in part useful for deterring predation by insects. Insects would of course naturally like to eat the leaves and the seeds of the coffee plant, but high levels of caffeine are toxic to them. And this relationship can be seen further in the fact that the fruit flied Drosophila drosoft la has the ability to taste the presence of certain compounds. I was reading about how they have an array of at least sixty eight known um These are called seven transmembrane goostatory receptors or gustatory receptors. Are g ours and uh gustatory, meaning taste. So these gustatory receptors allow the fly to sense the presence of compounds that could kill it or harm it and avoid eating them. Caffeine is one of those compounds. Fruit Flies appear to have a suite of receptors, including one called g R sixty six A, that work together to sense the presence of caffeine in whatever they're they're eating and allow an avoidance response to take over. Now, I think it's interesting to put that together with the fact that in the human experience, most alkaloids taste Bitter alkaloids are a broad class of nitrogen bearing organic compounds that plants make, many of which have physiological effects on humans and other animals, effects ranging from uh, you know, all your standard types of poisoning and death too, psychoactive effects such as the stimulant effect of caffeine. So bitter taste often causes animals to reject act to food source. So I think it's kind of reasonable to put all this together in wonder if the sensation of bitterness when ingesting plants rich in alkaloids is perhaps a protective response that tells us to stop consuming these plants and reject them, similar in effect to the way that a fruit fly has the ability to taste and reject caffeine, though with a different evolutionary backstory. Yeah, that's a good point. I mean, it makes me think of, you know that the obvious of example of say, a child being introduced to coffee and finding it disgusting, um because it is bitter uh and um, you know, you know, And also we have to think about the fact that that the chocolate unsweetened has a very bitter taste to it as well, though of course in both cases coffee and chocolate. Uh, there is of course a process involved here. Uh, we're not gonna really get into with coffee and and chocolate between plant and and even the unsweetened food product. But that's something we can come back to in the future. I don't have to do something on chocolate saying a few it too, absolutely, And yeah, it's interesting to think about are the complex human reaction or response to bitterness that it seems bitterness is probably primarily biologically relevant in getting us to reject foods. You know. It's like this has something in it that I don't want to get too much of, so I probably don't want to eat too much of this. Yeah. So many of the naturally occurring pesticides that we consume, h yeah, they have some sort of a strong flavor that would tend to convince most humans to avoid them, certainly, and in many of the cases with our various spices, avoid them in larger quantities than we traditionally use them. And yet we can really get a taste for them. I mean, I like the bitter taste of coffee and of chocolate and of tea and so forth. It might have to do with like it's a level of bitterness that doesn't reach kind of a threshold at which you would find it disgusting, like it's like below the bar for rejection. Or it could be a totally it could be a learned response. Maybe naturally people don't bitter stuff in any quantity, but if culturally they learned to appreciate it, I don't know, maybe maybe that's what's making the difference there. Oh, I mean in cocktail culture, for example, you you know have a you know, a whole spectrum of bitter drinks. You know, sometimes you're just adding a little bitter taste via bitters in many cases to u to to offset sweetness and give you a certain flavor profile. But some people go especially hard for those those bitter drinks. They're like, I've never tried one of these, but you have these recipes floating around for mixed drinks that contain like multiple bitter components to try and create like some sort of uber bitter concoction, which is not for me, but I I assume it is for some people who have developed a taste for all of those bitter components. Well, I mean, I do think about how many of the bitter food, almost all of the really enjoyable bitter foods and beverages I can think of or psychoactive in one way or another. I mean, I it's not like, you know, bitter greens or you know, I like greens that can be better. But I think of coffee which has caffeine. I think of chocolate which has caffeine. I think of tea which has caffeine. Or I think of alcoholic beverages that are bitter, like you know, like hoppy beers and so forth. Yeah. So it's almost like on some level of our bodies saying this tastes bad, but something good is happening. Yeah, but okay. So caffeine one of its roles within a plant might be to deter insects or other animals, maybe from eating the leaves of the plant. They got enough caffeine in there. One way or another, the toxicity of the caffeine will drive the animal away. Another interesting idea that Zimmer races in this article is that caffeine in coffee plants is suspected to work also by inhibiting the growth and germination of other plants. He writes that when coffee leaves die and fall off of a coffee plant, they fall down to the soil below, the caffeine content seeps into the earth and interferes with the ability of other plant species in the soil nearby to germinate. So this helps limit competition for soil resources and sunlight in the area. Now, I didn't find anything specifically about whether or not that's true with tea plants as well, but it could also be the case if if it works for the coffee plant. But one thing where I did find a parallel between how they think caffeine is working in coffee plants and tea plants is its role in pollination. I thought this was the most interesting of all. So in addition to deterring insect or animal predation and perhaps limiting competition from nearby plants, UH, the psychoactive and drug like properties of caffeine on animals might be not only an unintended byproduct or side effect of their physical logical activity as a deterrent, they might actually be in part the point of the compound, or at least one of the points of the compound, and it would work like this. So coffee and flowering plants that produce caffeine in their leaves also produce lower doses of caffeine in their nectar. Now, plants make nectar as a food for insects as an incentive for insects to spread their pollen. You know, So the insect gets sugar from the plant, it gets a meal, and the plant gets helped with reproduction and dispersal when returning, gets help spreading its genetic material. Now here's the really interesting thing. Research has shown that when insects feed on plant nectar containing low doses of caffeine, they seem to become more disposed to remember the scent of the flower where they consumed that nectar, and researchers believe this may cause the insect to return to that flower more off fen and thus spread its pollen more effectively. So maybe out of just one compound there is one molecule that the plant creates, it can be getting multiple completely different effects depending on the dosage in the different part of the plant. So maybe higher levels in the leaves will deter insects from trying to eat the leaves, but lower levels in the nectar will be more like a cup of coffee for the insects, which kind of like boosts the insects memory and allows it to return to the same plant more frequently and spread that plant's genetic material toxic and high concentration, but beneficial to some types of brain function at lower doses. Uh. And it's funny that caffeine has the same dual effect on humans. I mean, if you have too much of it, it will kill you. But if you have these low doses of it that people consume in beverages and stuff, people use it directly as a stimulant to improve their brain function. Yeah. I mean, coming back to Shino the mythical um story here, it's basically a uh an individual god figuring out to what degree one should consume the world of poisons around us, like how much of this poison is appropriate for desired outcome? Um, and in which poison should we not mess with at all? Exactly. So I found this so interesting. But anyway, this was all about the coffee plant. I was trying to find is the same thing true of the tea plant? And I did, in fact find. A study from just a couple of years ago, was from one published in the Journal of Insect Physiology. It was by g Win Gong at All, and it was called Floral t polyphenols can improve honey bee memory retention, and olfactory sensitivity. So the background on the study is to read from their abstract quote. Animal pollinated plants face a common problem how their defensive anti herbivore compounds may impair or alter pollinator behavior. Evolution has tailored multiple solutions which will largely involve pollinat or tolerance or manipulation to the benefit of the plant, not the removal of these compounds from pollen or nectar. The tea plant Camillia sinensis is famous for the caffeine and te polyphenols that it produces in its leaves. However, these compounds are also found in its nectar, which honeybees readily collect. So to summarize here, the authors tested the effects of these two different products of the tea plant, the of the caffeine and the tea polyphenols UH, and they tested it on the forging behavior of honeybees. And what they say they found is that honeybees preferred simulated nectar from a feeder when it contained te polyphenols over a control feeder that did not contain them. And they also found that bees that were fed on a feeder laced with caffeine showed small improvements in learning, Both caffeine and te polyphenols increased memory retention and showed influences on other behaviors as well, such as like response to alarm pheromones. So it seems that the tea plant may well be adapted to give pollinating insects small doses of caffeine and tea polyphenols for a reason. It could mean, among other things, that the pollinating insects are more likely to keep returning to the same plant and spreading its genetic material. And I thought this was so interesting. So if this is in fact the case, Uh, it's it's a more complex relationship than I usually imagine between plants and the alkaloids that they manufacture and the animals that they target, because I usually think of the relationship as a pretty simple one way interaction, like the the plant alkaloid causes some kind of negative physiological response or reaction in the animal, and then the animal is deterred from eating the plant again, or the animal is driven to evolve like gustatory receptors or taste that make the plant taste nasty from the first spite, because you know, it's ancestors that didn't have that may have died. But this is a more complex implied relationship. I don't know exactly what to compare it to. I mean, it's almost like the cultivating of an of an analog of an addiction, but one with UH. I don't know. Survival benefits for the bee as well, because it allows them to keep returning to a food source. So before we we got into all this year, I, if I were put to the test, I would have just said, well, caffeine implants is just about keeping some things from eating them, and we've managed to manipulate that situation for our own benefit. But yeah, it sounds like the reality is a lot more complicated. Of course, you can't really think about purpose and design and desire in the literal sense when it comes to the evolution of something like this in various plants species. But I am kind of reminded of how some products in the human world will end up with more than one purpose, Like, for instance, I think of bag bomb. Have you ever used bag bomb or seen a container bag bomb? I don't think so. Explain it's like a little greenkin and uh, I believe it dates back to her about eight and it was it's a salve to put on cow's utters after milking. But people started using it because they realized that, hey, you can put this on dry cracked skin, and so uh. I It's one of these things where it ended up being there's this whole additional application of the product, an entire different consumer base that kind of spraying out of it. It's more complicated, obviously with the case with caffeine and plants, but it's almost it almost feels like that where there may be one purpose that's kind of driving, uh, the evolution of this, but then this other use, this other way that it can enhance the survivability of of the plant, uh emerges as well, and so you have the sort of dual forces driving it at that point. Oh yeah. Evolution loves to repurpose pre existing morphology. Is so like a structure or a chemical capacity, or something that evolved initially for one reason can always be repurposed when a new opportunity presents itself. Yeah. And I don't know specifically what the order would have been in any of these cases, whether you're talking about coffee plants or tea plants, but you can imagine a compound Initially there is evolutionary pressure favoring the enzymes to produce that compound because it I don't know, because it deters predation by animals, or because it limits competition when the leaves fall into the soil. And then later something like this relationship with pollinators emerges using the same compound, and then eventually this relationship with with human beings who start cultivating it. So it's it's fascinating to think about all of these relationships. All right, we're gonna go ahead and wrap up this episode, but we'll be back in the next episode with more discussion of tea. In the meantime, of course, we'd love to hear from everyone out there. You might be thinking to yourself, well, I have some tidbit I want to share about tea. But but surely Robert and Joe don't want to hear it. No, we want to hear it. Right in. We want to know about your individual or cultural uh differences and um and and app tied for tea. If there there other myths or legends or folk tales that you've heard about about the origins of tea. Right in, we would love to hear from you. In the meantime, we'll remind you that stuff to blow your Mind is primarily a science podcast, with core episodes on Tuesdays and Thursdays. On Monday's we do listener mail. That's uh, That's when we will read the messages that come in about these episodes. On Wednesday's we do a short form artifact or monster fact episode, and then on Friday's It's Weird How Cinema Time. That's when we set aside most serious concerns and just talk about a strange film. Huge thanks to our audio producer J J. Pauseway. If you would like to get in touch with us with feedback on this episode or any other, to suggest a topic for the future, or just to say hello, you can email us at contact at stuff to Blow your Mind dot com. Stuff to Blow your Mind. It's production of I Heart Radio. For more podcasts for my Heart Radio, I Heart Radio app, Apple Podcasts, or wherever you're listening to your favorite shows.

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