And the fermented fruits also has led evolutionary biologists to understand in more detail our association, wide spread as a species, with alcohol. Really interesting
i wonder if the same connection is with us and smoking. our ancestors who enjoyed inhaling smoke from bonfires spent more time around them and had evolutionary advantages that harnessing fire gave. and now many people smoke cigarettes to satisfy that instinct.
@@beeqool I don’t buy that one. People smoke things that affect brain chemistry not just for the sake of smoke. Smoking tons that don’t isn’t that common
Also worth noting that the cell signaling for sour, which is just proton concentration, is very simple, and there are actually multiple pathways. But sweet and umami require complex, highly-specified receptor proteins.
The primate sour affinity is a chicken/egg problem. Did we start eating acidic foods because we lost the ability to make Vitamin C? Or did we lose the ability to make Vitamin C because we started eating acidic fruits? Hard to see how the mutation would survive in a population that wasn't already consuming external sources of Vitamin C.
Eons did an episode on the vitamin C pseudogene a while ago. I think the hypothesis is that apes were already eating a lot of fruit and therefore the vitamin C production gene was not subject to much selective pressure. Later, when fruit became a bit more scarce and the gene was already deactivated, it would have been advantageous to seek out sour foods.
I would have guessed that 'sweet' was the first taste, but the stuff about the pH of water was illuminating. That environmental sense is still there whenever I deal with lemons if I've got a papercut or a cracked cuticle- Yeowch! I love when these videos go into explaining our relationship to food, since it's something to visceral to existing, and definitive of culture, that I feel like I'm uncovering the meaning of life or something XD
@@lyrimetacurl0 Salt is an interesting prospect as depending on when taste senses arose it might be really important or really useless. After all in the ocean salt is everywhere, though certain specific salts can indeed be much rarer and thus more precious. Salinity detection however could be quite useful in poorly mixed waters and that could presumably be adapted to taste. More importantly however both salty and sour are linked to measuring ion concentrations which given that ion pumping is among the oldest most evolutionarily conserved features of life on Earth dating back at least to the Last Universal Common Ancestor it would be useful to have the ability to detect these some 4 billion years ago.
Sweetness is detected in a much more complicated way than the other tastes, there are multiple receptors for sugars, and the entire process is not completely understood as well as the other gustatory stimuli
@@kw2519 the acid refers to the carboxyl group, amino acids don’t typically effect pH very much, as they are not aggressively donating protons in a solution with water (low pkA)
Adding onto the fact, the molecule to activate the sour receptors in our tastebuds are incredibly simple. For sweetness, its sugar, for saltiness, its salt and minerals, for unami or savory, its MSG, and for bitter, its alot of moluecules or compounds. For Sourness, we just taste the Protons, or Hydrogen ion! The more hydrogen ion you have, the more acidic things are.
I was gonna comment on how low pH is expressed by H3O+ ions and not free protons, but checking out how the receptor in question (namely OTOP1) works I learnt that it literally only lets H+ ions pass! So we do literally taste free protons (under pH difference pressure)!
@@lusciouslocks8790 mostly feels like a superpower because it seems useful and we don't have it, right? "regular" human-level vision would be quite a superpower to those that don't have it
Color vision in primates is interesting since it evolved independently to the color vision in birds and reptiles... sort of. The ancestors of modern mammals were nocturnal and thus lost the ability of advanced color vision in their stem-mammal reptile-but-not-really ancestors. This may also explain why mammals arent as colorful as reptiles or birds. At some point in the evolutionary history of primates, a form of color vision was independently evolved, likely due to their diet of fruits. Being able to tell how ripe a fruit was gave them an advantage in foraging. Eventually color vision would open the door to more traits, like color-based social displays in animals like baboons, or the importance of color in our own art and culture.
Aside from the dangers of consuming too much acidic food, our sudden cutoff for "too sour" might also have helped in identifying unripe fruits, which don't offer as much nutritional value yet and are better left alone for a little bit longer. In that context it also seems likely that our sourness tolerance depends on how much sweetness is present at the same time. At least from anecdotal evidence I can more or less confirm that for myself, with even extremely sour candy being far more tolerable than something comparably less sour (but also far less sweet) like an unripe apple.
My favorite part of this Channel is not even the videos surprisingly. It’s reading some of the most thoughtful, inquisitive, just knowledgeable people in the comment section.
I wonder if our loss of the ability to synthesize vitamin c and the subsequent increase in our consumption of fermented fruits helped to develop our incredible sense of taste? Having a more refined palette might have been extremely advantageous to find food that was just fermented enough, but not so fermented as to be dangerous to eat?
Along with other weird human quirks. Spicy is supposed to ward off grazers, but humans actively try to breed more and more spicy peppers and stuff just for consumption. Same with certain stinky. Some people find durian fruit tasty
Another major reason though was actually our bigger brains. One sacrifice many don't know of our big brains is that to make room they had to grow sideways leading to our brain case being wider than our jaws. This is a problem cause in all other apes including early humans the jaw muscles go all the way around the skull and anchor to a ridge at the top. Humans lost this feature and our jaw muscles only attack about halfway up our skull which cuts our jaw strength significantly. This lower jaw strength severely reduced the amount of food items we could consume. A lot of tough fibrous food that other apes rely on were suddenly off the menu. So having a more refined palette become important cause the bulk food was no longer an option.
Sour taste in green leafy vegetables can also trigger our stomach acids to activate which helps in digestion. People used to eat things like dandelion greens. Or arugula before a meal to help their digestion.
I imagine that a carbonate-shelled invertebrate, such as a nautilus, might gain a survival advantage if it could taste waters too acidic for its shell and then move to other places or depths with unmixed water layers. At present oceanic pH is fairly consistent, mostly because of thermohaline circulation and deep mixing but that wasn’t always necessarily the case.
Something I’m curious about; I raise cattle and goats for dairy, and also hogs (decidedly NOT for dairy 😜)…how did some mammal species evolve to have their mammary system in between their back legs (like cows and goats) whereas others developed to have them between their front legs (like elephants and primates)? Specifically elephants surprise me, because it seems that quadrupeds seem to have them mostly located in the back, or else have a series of them from the chest to the rear (dogs, swine, cats, etc…) In asking the question, I just realized that the animals with multiple pairs are all omnivores or carnivores and the herbivores (minus elephants) are in the back. I watch your videos at milking time (pretty sure the goat does are watching with me. They seem to enjoy the video/snack time lol!) and it just got me wondering how the heck that all came to be. Mahalo!
@@robertfaler1947 didn't they go extinct after the Dumbo movie increased demand for stuffed elephants? I'd heard they were hunted to extinction in the 60's
Another great episode, as always. I like this series because they do not present the material as if it is an undisputed fact. Instead they present newly published research in a gentle, simple way for laymen to be able to understand it. In short, this channel doesn't simply teach us something, but rather invite us to think about the possibilities and new hypothesis.
Hey Eons team, wanted to let you know that this video inspired me to speak on this subject in a university course. I handed out sour warheads as a speaking aid. It was a great time and I really enjoyed speaking publicly for once. Thanks for the videos!
I wonder if sour's ubiquity has something to do with its relative simplicity rather than a great need. As sour is connected to the flow of hydrogen ions, it inherently involves electrical concepts like charge, current, etc. The flow of hydrogen ions in and out of a cell are basic biological interactions, and this is already half way to a basic sour taste. All you need to do is hook up a sensitive enough detector, or have an additional chemical pathway to amplify/direct the current to a local nerve. Given enough/complex enough circuitry (see vertebrates), maybe its hard not to have a nervous reaction to an inherently electrical activity.
I had Omicron in December and lost my sense of taste and smell except for bitter/sour foods and meats.I still haven't regained it completely.I can smell citrus scents but gourmand scents either have to very strong or very close.
I lost mine for all savory things. Could only taste sugar and sour. That was on christmas last year, and i still cant taste or smell right. Savory stuff smells rancid
I completely lost and gained my taste and smell with in 3 weeks post delta variant in 2020 Also got omicron in 2021 but it didn't effect my smell or taste
Not sure what variant we had, but got covid for new years 2021. Lost all smell and taste except for the tiniest bit of bitter and salt. They came back but about 3 weeks later things slowly started to smell bad and eventually tasting bad. Sour, fermented things seemed to get slightly more pungent but for the most part stayed smelling good and tasting good, too. Except for mustard, and oranges, they got way too sour. My smell and taste finally started getting a lot better the last few months.
I'd love to see an episode on dingoes and their relationship with Indigenous Australians. Particularly, I'd like to know if dingoes were domesticated or tamed by Indigenous Australians and then subsequently untamed or feralised, and how they came to be in Australia (ie. were they introduced). An episode on the evolution of ratites such as cassowaries would also be awesome
I’m interested about sour taste amongst birds. Many fruits that are bird specific (in terms of seed distribution) seem much too tart even for primates and are only used in sugar rich preserves or liquors.
Vids are great as always! You should do an episode or even a podcast episode on the artists who make the reconstructions. Would love to know their backgrounds!
That would be a fantastic podcast episode for people who are wondering how one gets into that as a career path or hobby. There are probably a lot of different paths to making artistic reconstructions, and it'd be neat to talk to about three or four people who have done it and see how they managed it.
I had a cat who loved sweet things. Cookies. Cakes. Soft candies. Fruit. I wonder if he had a typo that let him taste sweet... Cause he clearly liked it.
I wonder about that too, because one of my cats would lick suckers from a certain brand. That cat is fine, but the gas station doesn't sell those candies anymore.
Same, one of mine (still alive and well at 18) shows a clear preference for caramel, dulce de leche and other super sweet ice cream. I've always found the claim of cats not being able to taste the sweet flavour highly suspicious.
Two of my cats are like that. I wonder if their domestication and a diet that's now higher in grains and sugars due to proximity to humans is affecting that.
As much as I love pbs eons, my life is immensely better thanks to this host. Your energy, magnetism and passion don’t get lost on this fellow human. You give me such gorgeous bliss vibes! A fan through and through 🌷🌷🌷🌷🌷 Thanks to the whole team for teaching me ALWAYS.
Could it be that the abundance of sour fruit (post dinosaurs) lead to the vitamin c gene becoming a psudogene? Like the classic “you don’t use it, you lose it” like cave albinism/blindness.
Check out another video by this channel focussing on this aspect Clearly we primates had been consuming more vit C in fruits (Edit: and any food source with vit C) hence the gene lost its function
You don't specifically need citrus or sour fruit to get sufficient vitamin C, those are just the highest concentration sources. Any diet that involves an abundance of fresh fruits and vegetables will also have enough dietary vitamin C intake to avoid a deficiency, which would result in a situation where the vitamin C production gene could easily get broken without any sort of fitness consequences.
I would be wary about the causality you propose here. Traits are not gained or lost because the environment "needs or doesnt need" them but because a mutation happens. In the case of the Vitamin C gene, sure it wasnt the most useful of traits and seems to more or less have been of neutral value. The mitation that knocked out its production is therefore a neutral mutation and these become predominant in populations largely through random chance via genetic drift. Overall, there is nothing inevitable about losing the function of the vitamin C gene, its more of less an accident of evolution at the time.
When I got covid the only thing that was affected was my ability to smell and taste sour and fermented foods, I didn’t loose it all together but instead it started smelling and tasting like the scent of bleach or ammonia It was really difficult for me because so much of the food we eat has at least some sour component to it even things like ketchup, mustard, and tartar sauce were out
We should develop a sour scale like the Scoville hotness scale is to peppers. What's the most sour thing you ate? And how sour was it? I have so many questions.
Happy I remembered enough from previous Eons episodes to predict that the reason we evolved to like sour was because we lost the ability to make our own vitamin C!
For some reason my brain read the title as “Why your soulmate may be the oldest taste” As you can imagine I was thoroughly confused at what this video was about.
So, is it that the genes for sour are still important for so many animals or could it be that the sour-tasting phenotype is tied to other life-critical functions? I mean, is the same ion channel used elsewhere? Like, maybe our bodies use the same sensor for measuring blood, stomach acid, or blood pH unconsciously? Yeah, an ancient fish could sense sour, but that doesn't explain why it was kept.
The same gene is also necessary for the formation of Otoconia in the inner ear, which are crystals which are an important part of the vestibular system and help us sense gravity and directional acceleration. This was actually the function for the gene that was known prior to it being determined to be a proton channel and a sour taste receptor, hence the name Otopetrin. Genes in the family also seem to be important in shell formation in some invertebrates.
@@jacksonwalker8748 oh, interesting! So the ion channel in question is/was used to transport the minerals ions? Weird. That would make sense why it'd be so conserved.
@@Infernoraptor The ion channel itself only allows protons through, but it seems like the change in pH as a result is necessary for the formation of the calcium carbonate crystals themselves.
I just wanted to say I'm enjoying your increased use of stock footage instead of reusing the same graphics repeatedly. I think you did a very good job especially in this video, compared with the other stock-footage-heavy channels that I watch. So many just put up some vaguely relevant image or video. In my estimation, you chose yours much more carefully and they actually support your communication rather than simply break it up. Good job!
I've always wondered as to the evolution of our emotions; when did our ancestors brains start to develop the ability to care for others around us? How did the brain evolve in the first place? What environmental forces set the course in motion for a three pound lump of muscle containing 86 billion neurons to exist?
I suggest reading Mutual Aid: A Factor of Evolution by Pyotr Kropotkin its pretty old, from the 1900s, but it was very controversial at the time since it also attacked the concept of social darwinism. Reading it with some hindsight also gives some nice insight into how these challenges to scientific dogma also interacted with radical politics of the time since Kropotkin was both a scientist and revolutionary (born noble but gave up priveledge and worked towards abolishing monarchy)
Brain evolution is quite complex since it seems the structures we call brains i.e. concentrated nerve clusters have evolved many times from ancestral nerve nets What the ancestral functions of nerves first were is an unresolved question since neurons do so many jobs within animals. For example while hydras are morphologically quite simple their nervous systems have been shown to control immune responses in addition to coordinating motion, what is more unusual in hydras and other hydrozoans however is that it appears that rather than using chemical gradients organized by HOX gene clusters to coordinate body alignment they control body alignment directly via their nervous systems without another chemical intermediary.
No one knows for sure how the brain developed, but it's thought that eyes came first, then the brain developed around the eyes as a way to process what they saw. At least in vertebrates.
It would be interesting to expand that study outside of vertebrates, see what else might react to sour - it wouldn't surprise me if it's older than that, and something that was common to much of the evolutionary tree, as even single cells would probably want to stay away from acids.
Now that I’ve seen this, it kind of makes sense. First Sour, then Spice, then Sweet, and then you got Bitter and Bland coming in at the end. This is just based of whenever you taste fruits, for me primarily Mangoes and Citruses. Notice how it’s a sting, then sweet, then the sourness, when you go for a bite or sip on it, more so on Citruses (Lemon, Limes, etc) In mangoes it’s more noticeable when you’ve had the same fruit in two stages the unripe sour or bland green, and the ripe/overripe sweet or tangy yellow.
Though we lost the final step in making our own Vitamin C, our bodies still produce the immediate precursor to it, L-gulonolactone. I'd like to see more study done on this ester to determine what advantage is provided by losing the ability to produce acsorbic acid (which, contrary to parsimony, guinea pigs ALSO did)
Parsimony isn't the only answer to all of biology, but is one of the most obvious by it's reasoning. Guinea pigs loosing the ability to make vitamin C could have been because they may have faced similar pressures as our primate ancestors.🤷♂️
It's not really contradictory to parsimony, it's just a matter of what the most parsimonious solution is. If you look at 20 species and two of them have a trait, and the other 18 don't, then it probably was convergent evolution. If 18 of them have a trait and two don't, it's more likely that it evolved once, and was lost in two lineages. Basically whatever involves the fewest steps is most likely.
what's crazy about this is sour maps to the pain regions of the brain, while all other tastes map to a "taste" region of the brain. While my neuroscience class was hypothesizing why, I remembered this video!
Maybe our fish ansestors actually were drawn to the acid because their food liked it and it helped it find that. And remember, there r different levels of sour so its still protective to us. Like dangerously rotten food has a whole different sour taste, and smell, than a lemon.
smell and taste are very closely linked, at least in humans. they are quite similar senses, both detecting chemicals. it wouldnt surprise me if both share a common evolutionary origin
Taste is sweet, sour, salty, bitter, and umami. These are detected by receptors on the tongue. Smell is detected by scent receptors inside the nose. These have a significantly wider range and include floral, minty, earthy, etc scents.
I'd not even really thought about the evolution of taste before, but of course it would have to be selected for like everything else. Really fascinating episode!
@@Neenerella333 In turning it back on through gene therapy, could a vitamin c deficiency be a problem of the past? Though, would individuals who recieve the treatment become adverse to sour foods?
@@andrewbeeco967 I don't know that they'd necessarily develop an aversion to sour foods. Part of the reason people get away with recommending vitamin C for _everything_ is that our bodies can get rid of excess fairly readily. So while overdosing on other vitamins can have severe side effects, too much C will probably just end up giving you more acidic urine.
This resoning seems quite finalist to me. Is there no molecular or developmental explanation to explain the robustness of sour taste among vertebrates? Most importantly, is there any other living being that is not a vertebrate who can taste sour?
I'm not sure about all cats not being able to taste sweets, I had one that loved sweets, if I was eating a cake he would jump right into my plate and then eat the whole slice from the ground, and he never did that with any other food! He also didn't liked cats food in general though, and would prefer human foods, like soups, stews, and, of course, grilled meat. Wouldn't eat any raw meat as well.
Or your cat had a mutation that let it taste sweet also you shouldn’t let cats eat anything with veggies or fruit in it cause they are carnivores nor Omnivores or herbivores you should only give them meat
The oldest and best -- I love sour foods! I can easily see how it'd be useful for an animal that can't make its own vitamin C. Still seems odd that it didn't go the GULOP route in any other vertebrate, though ... 04:21 -- Spots mean it's a baby deer, antlers mean it's an adult, argh my brain is confoozd!
@@cmelton6796 It's the typo-ridden gene we have that used to code for the making of vitamin C before it mutated. It just seems strange that it was important enough to keep hanging around for animals that can make their own vitamin C.
This is so interesting. A lot more interesting than I expected. I thought it might have something to do with vitamin C but I never imagined it would have to do with fermentation
I'm really happy that you used both "umami" and "savoury" as synonyms, rather than also acting as if we've never had a word for the flavor until a Japanese scientist identified it. It's not one of those big issues regarding international word borrowing, but it's just always been strange that the flavor that English already has for meats, most mushrooms, and other... well, savory things has been getting shunted aside in favor of a foreign word that describes meaty, mushroomy-type flavors
I dunno about every language but I wonder if umami caught on because other languages didn't have a word for it. For example, in Spanish people use umami to mean 'savoury' because the closest words in Spanish (that I know of) are 'sabroso' which means 'tasty' and 'salado' which means salty.
@@origaminosferatu3357 It could be that, though I'd still wonder why English speakers seemed so eager to ditch the pre-existing synonym. It may also be that "umami," being officialized in chemistry, is supposed to be a more so-called proper word, whereas "savory" is more a word for the masses. The scientific fields do get weird about language every once in a while. It is interesting that Spanish doesn't have a common word for it. With it being one of the five or so base flavors, I assumed that every language had a word for each one. I guess it's another example that language is the view of the people that speak it, not a mechanical thing
@@remen_emperor I could be wrong, that's just what I've gleaned from two years living here. But if I've learned anything about languages it's that they're anything but mechanical.
This really does make sense when you think about how we tend to only enjoy sour foods when we expect them to be sour. If a food surprises us we tend to be unsettled and hesitant to keep eating it, versus something we already know we can eat without consequence or threat of danger.
I would argue that the ability to sense sodium an thus, to perceive salty taste, is far more ancestral. Being crucial even for invertebrates and single cell organisms for basic cellular functions, it must have been the oldest taste..
@@lyrimetacurl0 : My point was that salty is unlikely to be the oldest taste. From the very beginning, ocean life was immersed in salty water, and thus had no need to seek sodium (or potassium, or other elements in seawater).
@@brothermine2292 well, that's exactly the point.. when you are in an environment that is very rich in osmoticly active ions, and you are an organism that is extremely sensitive to changing osmotic pressure and also utilizing the same ions for many living functions, be sure you'll need to be able to detect said ions and their concentration around you.. not for nothing most any form of living cell is equipped with Na pumps.. btw, idk if you actually watched the video, but according to them, the presence of acid in dangerous quantities brought about the advantageous ability to sense it, why would you think it wouldn't be the same for other bio active ions?
@@brothermine2292 in fact the very idea that the presence of something exclude the need to be aware of it is baffling to me.. there is no other reason to evolve the ability to sense something... organisms that don't get a certain stimulus don't waste energy on building sensory apparatus to detect it.. basic fact of evolution..
Thank goodness sour was associated with danger now I can make the excuse that I’m weak to sour candies because my primal instincts came out extra strong 💪🏽😂
One would think that's obvious. It's just pH after all. Trivial to detect. Similarly I would bet on saltiness being the number 2. Now bitterness is much more interesting
Regular air doesn't need to be detected because if we need it, then we don't need to look for it because it's in great abundance; and if it's bad for us, there's no point in trying to avoid it because it's everywhere.
It's really cool to see the proposed evolutionary story of an ion channel (OTOP or otopetrin) initially revealed as playing a role in maintaining the pH in the semicircular canals, the utricles and the saccules! (pH in these balance-sensing inner ear organs are critical to maintaining the small calcium carbonate stones/crystals!)
This is one of those topics you never really think about, but are incredibly fascinating once you do.
Quite a lot of science is like that. It's why we should investigate everything, you never know what you'll uncover.
Agreed. That's why I love this channel so much...
Yeah... 😋 I can live without sweet but I can't live without sour ....🍋
Or like me just so happened to be a question I Googled at 4 am two weeks ago.
never look at the middle on 2:08 please dont
And the fermented fruits also has led evolutionary biologists to understand in more detail our association, wide spread as a species, with alcohol.
Really interesting
Alcohol: The cause and solution to all problems!
I'll drink to that!
Beat me to it. But yeah certain early Ubaidian ceramics have telltale alcohol residue that predates agriculture proper
i wonder if the same connection is with us and smoking. our ancestors who enjoyed inhaling smoke from bonfires spent more time around them and had evolutionary advantages that harnessing fire gave. and now many people smoke cigarettes to satisfy that instinct.
@@beeqool I don’t buy that one. People smoke things that affect brain chemistry not just for the sake of smoke. Smoking tons that don’t isn’t that common
Also worth noting that the cell signaling for sour, which is just proton concentration, is very simple, and there are actually multiple pathways. But sweet and umami require complex, highly-specified receptor proteins.
The primate sour affinity is a chicken/egg problem. Did we start eating acidic foods because we lost the ability to make Vitamin C? Or did we lose the ability to make Vitamin C because we started eating acidic fruits?
Hard to see how the mutation would survive in a population that wasn't already consuming external sources of Vitamin C.
I got my money on a combination of both. It probably depended on population.
Agreed. Always thought losing the ability to produce vitamin C is very deadly. I am surprised they overcame that difficulty and survived.
They made a video on that lol
Eons did an episode on the vitamin C pseudogene a while ago. I think the hypothesis is that apes were already eating a lot of fruit and therefore the vitamin C production gene was not subject to much selective pressure. Later, when fruit became a bit more scarce and the gene was already deactivated, it would have been advantageous to seek out sour foods.
You answered your own question
I would have guessed that 'sweet' was the first taste, but the stuff about the pH of water was illuminating. That environmental sense is still there whenever I deal with lemons if I've got a papercut or a cracked cuticle- Yeowch! I love when these videos go into explaining our relationship to food, since it's something to visceral to existing, and definitive of culture, that I feel like I'm uncovering the meaning of life or something XD
I thought it would be salt
@@lyrimetacurl0 Salt is an interesting prospect as depending on when taste senses arose it might be really important or really useless. After all in the ocean salt is everywhere, though certain specific salts can indeed be much rarer and thus more precious. Salinity detection however could be quite useful in poorly mixed waters and that could presumably be adapted to taste.
More importantly however both salty and sour are linked to measuring ion concentrations which given that ion pumping is among the oldest most evolutionarily conserved features of life on Earth dating back at least to the Last Universal Common Ancestor it would be useful to have the ability to detect these some 4 billion years ago.
Sweetness is detected in a much more complicated way than the other tastes, there are multiple receptors for sugars, and the entire process is not completely understood as well as the other gustatory stimuli
I mean amino ACID.
@@kw2519 the acid refers to the carboxyl group, amino acids don’t typically effect pH very much, as they are not aggressively donating protons in a solution with water (low pkA)
Adding onto the fact, the molecule to activate the sour receptors in our tastebuds are incredibly simple. For sweetness, its sugar, for saltiness, its salt and minerals, for unami or savory, its MSG, and for bitter, its alot of moluecules or compounds.
For Sourness, we just taste the Protons, or Hydrogen ion! The more hydrogen ion you have, the more acidic things are.
Fascinating! Would be loved if that was included in the video. I wonder if the original research paper/s went into it any.
Never forget children, to avoid vitamin C deficiency and scurvy, consume 100% orange juice.
I never thought about that, but yeah acidity is literally just a high concentration of H+ ions. Wow!
I was gonna comment on how low pH is expressed by H3O+ ions and not free protons, but checking out how the receptor in question (namely OTOP1) works I learnt that it literally only lets H+ ions pass!
So we do literally taste free protons (under pH difference pressure)!
This is why the parsimony argument is weak. Taste for sour could have evolved many times because it is so simple.
It would be interesting to find out when other senses evolved in certain creatures. Especially those that convergentley evolved them
Yeah. Like eyes. A lot of them convergentley in vertebrates and invertebrates
I like electroreception but that might just be because it feels like a superpower
@@lusciouslocks8790 mostly feels like a superpower because it seems useful and we don't have it, right? "regular" human-level vision would be quite a superpower to those that don't have it
Color vision in primates is interesting since it evolved independently to the color vision in birds and reptiles... sort of. The ancestors of modern mammals were nocturnal and thus lost the ability of advanced color vision in their stem-mammal reptile-but-not-really ancestors. This may also explain why mammals arent as colorful as reptiles or birds. At some point in the evolutionary history of primates, a form of color vision was independently evolved, likely due to their diet of fruits. Being able to tell how ripe a fruit was gave them an advantage in foraging. Eventually color vision would open the door to more traits, like color-based social displays in animals like baboons, or the importance of color in our own art and culture.
Yeah
Aside from the dangers of consuming too much acidic food, our sudden cutoff for "too sour" might also have helped in identifying unripe fruits, which don't offer as much nutritional value yet and are better left alone for a little bit longer.
In that context it also seems likely that our sourness tolerance depends on how much sweetness is present at the same time. At least from anecdotal evidence I can more or less confirm that for myself, with even extremely sour candy being far more tolerable than something comparably less sour (but also far less sweet) like an unripe apple.
Sensible hypothesis. I, too, tend not to tolerate much sourness unless it is paired with sweetness.
My favorite part of this Channel is not even the videos surprisingly. It’s reading some of the most thoughtful, inquisitive, just knowledgeable people in the comment section.
I wonder if our loss of the ability to synthesize vitamin c and the subsequent increase in our consumption of fermented fruits helped to develop our incredible sense of taste? Having a more refined palette might have been extremely advantageous to find food that was just fermented enough, but not so fermented as to be dangerous to eat?
*palate
True, one of the possible explanations on why humans have such a wide pallets while most animals stick to the same types of food
Yes, clearly sour taste has indeed a nutritional benefit.
Along with other weird human quirks. Spicy is supposed to ward off grazers, but humans actively try to breed more and more spicy peppers and stuff just for consumption. Same with certain stinky. Some people find durian fruit tasty
Another major reason though was actually our bigger brains.
One sacrifice many don't know of our big brains is that to make room they had to grow sideways leading to our brain case being wider than our jaws. This is a problem cause in all other apes including early humans the jaw muscles go all the way around the skull and anchor to a ridge at the top. Humans lost this feature and our jaw muscles only attack about halfway up our skull which cuts our jaw strength significantly.
This lower jaw strength severely reduced the amount of food items we could consume. A lot of tough fibrous food that other apes rely on were suddenly off the menu. So having a more refined palette become important cause the bulk food was no longer an option.
Sour taste in green leafy vegetables can also trigger our stomach acids to activate which helps in digestion. People used to eat things like dandelion greens. Or arugula before a meal to help their digestion.
Those are bitter, not sour.
@@Erewhon2024 I actually meant to say sour and bitter. But the do both trigger digestive enzymes.
@Timothy Iorlano yea but sour and bitter help to trigger digestive enzymes that aid in digestion.
I imagine that a carbonate-shelled invertebrate, such as a nautilus, might gain a survival advantage if it could taste waters too acidic for its shell and then move to other places or depths with unmixed water layers.
At present oceanic pH is fairly consistent, mostly because of thermohaline circulation and deep mixing but that wasn’t always necessarily the case.
I would not have made that connection, but it certainly sounds like something to explore in detail. Thanks.
that's exactly what i thought when i saw the cover and title
Something I’m curious about; I raise cattle and goats for dairy, and also hogs (decidedly NOT for dairy 😜)…how did some mammal species evolve to have their mammary system in between their back legs (like cows and goats) whereas others developed to have them between their front legs (like elephants and primates)? Specifically elephants surprise me, because it seems that quadrupeds seem to have them mostly located in the back, or else have a series of them from the chest to the rear (dogs, swine, cats, etc…) In asking the question, I just realized that the animals with multiple pairs are all omnivores or carnivores and the herbivores (minus elephants) are in the back. I watch your videos at milking time (pretty sure the goat does are watching with me. They seem to enjoy the video/snack time lol!) and it just got me wondering how the heck that all came to be. Mahalo!
It's because elephants used to be bipedal, until a few hundred thousand years ago
@@kevinradtke3767
Really? What? Holy crap, giant pedal elephants? (Probably not as giant, but holy)
@@kevinradtke3767 damn forreal?
@@kevinradtke3767 Bipedal elephants still exist. They are a shade of pink and can be seen in the Dumbo movie.
@@robertfaler1947 didn't they go extinct after the Dumbo movie increased demand for stuffed elephants? I'd heard they were hunted to extinction in the 60's
Another great episode, as always. I like this series because they do not present the material as if it is an undisputed fact. Instead they present newly published research in a gentle, simple way for laymen to be able to understand it. In short, this channel doesn't simply teach us something, but rather invite us to think about the possibilities and new hypothesis.
Hey Eons team, wanted to let you know that this video inspired me to speak on this subject in a university course. I handed out sour warheads as a speaking aid. It was a great time and I really enjoyed speaking publicly for once. Thanks for the videos!
I wonder if sour's ubiquity has something to do with its relative simplicity rather than a great need. As sour is connected to the flow of hydrogen ions, it inherently involves electrical concepts like charge, current, etc. The flow of hydrogen ions in and out of a cell are basic biological interactions, and this is already half way to a basic sour taste. All you need to do is hook up a sensitive enough detector, or have an additional chemical pathway to amplify/direct the current to a local nerve.
Given enough/complex enough circuitry (see vertebrates), maybe its hard not to have a nervous reaction to an inherently electrical activity.
I had Omicron in December and lost my sense of taste and smell except for bitter/sour foods and meats.I still haven't regained it completely.I can smell citrus scents but gourmand scents either have to very strong or very close.
I lost mine for all savory things. Could only taste sugar and sour. That was on christmas last year, and i still cant taste or smell right. Savory stuff smells rancid
Now it’s april, that’s long time of side effect
I completely lost and gained my taste and smell with in 3 weeks post delta variant in 2020
Also got omicron in 2021 but it didn't effect my smell or taste
Not sure what variant we had, but got covid for new years 2021. Lost all smell and taste except for the tiniest bit of bitter and salt. They came back but about 3 weeks later things slowly started to smell bad and eventually tasting bad. Sour, fermented things seemed to get slightly more pungent but for the most part stayed smelling good and tasting good, too. Except for mustard, and oranges, they got way too sour. My smell and taste finally started getting a lot better the last few months.
I heard there’s some kind of therapy for that.
I love this channel. It gives so much depth to some of the random questions we all think about from time to time.
Agreed
And also questions we never even think about, but fascinate us once we do...
I'd love to see an episode on dingoes and their relationship with Indigenous Australians. Particularly, I'd like to know if dingoes were domesticated or tamed by Indigenous Australians and then subsequently untamed or feralised, and how they came to be in Australia (ie. were they introduced). An episode on the evolution of ratites such as cassowaries would also be awesome
I’m interested about sour taste amongst birds. Many fruits that are bird specific (in terms of seed distribution) seem much too tart even for primates and are only used in sugar rich preserves or liquors.
Vids are great as always! You should do an episode or even a podcast episode on the artists who make the reconstructions. Would love to know their backgrounds!
That would be a fantastic podcast episode for people who are wondering how one gets into that as a career path or hobby. There are probably a lot of different paths to making artistic reconstructions, and it'd be neat to talk to about three or four people who have done it and see how they managed it.
I had a cat who loved sweet things.
Cookies. Cakes. Soft candies. Fruit.
I wonder if he had a typo that let him taste sweet... Cause he clearly liked it.
I wonder about that too, because one of my cats would lick suckers from a certain brand. That cat is fine, but the gas station doesn't sell those candies anymore.
My cat growing up liked sugar cookies, and cream cheese frosting.
He also liked pork rinds.
Same, one of mine (still alive and well at 18) shows a clear preference for caramel, dulce de leche and other super sweet ice cream. I've always found the claim of cats not being able to taste the sweet flavour highly suspicious.
And none of you have thought to just wonder how these things taste when you remove the sweetness from them and if cats would like that?
Two of my cats are like that. I wonder if their domestication and a diet that's now higher in grains and sugars due to proximity to humans is affecting that.
As much as I love pbs eons, my life is immensely better thanks to this host. Your energy, magnetism and passion don’t get lost on this fellow human. You give me such gorgeous bliss vibes! A fan through and through 🌷🌷🌷🌷🌷 Thanks to the whole team for teaching me ALWAYS.
Could it be that the abundance of sour fruit (post dinosaurs) lead to the vitamin c gene becoming a psudogene? Like the classic “you don’t use it, you lose it” like cave albinism/blindness.
I believe that's the dominant hypothesis, as stated in the video about that gene from a while ago.
Check out another video by this channel focussing on this aspect
Clearly we primates had been consuming more vit C in fruits (Edit: and any food source with vit C) hence the gene lost its function
You don't specifically need citrus or sour fruit to get sufficient vitamin C, those are just the highest concentration sources. Any diet that involves an abundance of fresh fruits and vegetables will also have enough dietary vitamin C intake to avoid a deficiency, which would result in a situation where the vitamin C production gene could easily get broken without any sort of fitness consequences.
@@rocketsocks Yup u're right
I would be wary about the causality you propose here. Traits are not gained or lost because the environment "needs or doesnt need" them but because a mutation happens. In the case of the Vitamin C gene, sure it wasnt the most useful of traits and seems to more or less have been of neutral value. The mitation that knocked out its production is therefore a neutral mutation and these become predominant in populations largely through random chance via genetic drift.
Overall, there is nothing inevitable about losing the function of the vitamin C gene, its more of less an accident of evolution at the time.
Loved this episode as always :) Thank you Eons for consistently providing quality content
An ancient fish developing a way to sense predators to stay alive 500 million years ago -> me enjoying a sour apple gummy
The optimal outcome
Love when my field of work (gastronomy) intersects with topics of this channel. 🍳🦖
When I got covid the only thing that was affected was my ability to smell and taste sour and fermented foods, I didn’t loose it all together but instead it started smelling and tasting like the scent of bleach or ammonia It was really difficult for me because so much of the food we eat has at least some sour component to it even things like ketchup, mustard, and tartar sauce were out
Thank you for answering a question I didn't know I had :) Astonishing as always !
And yay, Miss Cool Teacher is back :)))
We should develop a sour scale like the Scoville hotness scale is to peppers. What's the most sour thing you ate? And how sour was it? I have so many questions.
Thank you eons for the great content.
You're my favorite presenter and it's great to see you as always, whatever the topic is
I don't know who or what invented Sourness yet but THANK YOU FOR SOUR CANDIES THEY'RE THE BEST
Living things did not invent sourness
Creatures evolved around sourness
I'm eating sour right now. :)
PBS Eons: the answer to all the questions I never knew I wanted to know till now
Happy I remembered enough from previous Eons episodes to predict that the reason we evolved to like sour was because we lost the ability to make our own vitamin C!
Love how PBS Eons turned this extremely mundane information into a dramatic narrative with some clever writing & editing
Fascinating topic. You learn new things all the time.
IV BEEN WAITING SINCE I GOT TO WORK TO WATCH THIS YALL POSTED IT THE SECOND I WALKED IN
Life gives you lemons first because sour is the oldest.
For some reason my brain read the title as “Why your soulmate may be the oldest taste”
As you can imagine I was thoroughly confused at what this video was about.
So, is it that the genes for sour are still important for so many animals or could it be that the sour-tasting phenotype is tied to other life-critical functions? I mean, is the same ion channel used elsewhere? Like, maybe our bodies use the same sensor for measuring blood, stomach acid, or blood pH unconsciously?
Yeah, an ancient fish could sense sour, but that doesn't explain why it was kept.
The same gene is also necessary for the formation of Otoconia in the inner ear, which are crystals which are an important part of the vestibular system and help us sense gravity and directional acceleration. This was actually the function for the gene that was known prior to it being determined to be a proton channel and a sour taste receptor, hence the name Otopetrin. Genes in the family also seem to be important in shell formation in some invertebrates.
@@jacksonwalker8748 oh, interesting! So the ion channel in question is/was used to transport the minerals ions? Weird. That would make sense why it'd be so conserved.
@@Infernoraptor The ion channel itself only allows protons through, but it seems like the change in pH as a result is necessary for the formation of the calcium carbonate crystals themselves.
I just wanted to say I'm enjoying your increased use of stock footage instead of reusing the same graphics repeatedly. I think you did a very good job especially in this video, compared with the other stock-footage-heavy channels that I watch. So many just put up some vaguely relevant image or video. In my estimation, you chose yours much more carefully and they actually support your communication rather than simply break it up. Good job!
I love how these always start with a story. 'a fish was swimming carefree...'
It's early morning, I'm not fully awake, and I originally misread the title as "Why Souls May Be the Tastiest" and was scared.
I love the dad jokes at the end 😂
Brilliant presentation
I've always wondered as to the evolution of our emotions; when did our ancestors brains start to develop the ability to care for others around us? How did the brain evolve in the first place? What environmental forces set the course in motion for a three pound lump of muscle containing 86 billion neurons to exist?
I suggest reading Mutual Aid: A Factor of Evolution by Pyotr Kropotkin
its pretty old, from the 1900s, but it was very controversial at the time since it also attacked the concept of social darwinism. Reading it with some hindsight also gives some nice insight into how these challenges to scientific dogma also interacted with radical politics of the time since Kropotkin was both a scientist and revolutionary (born noble but gave up priveledge and worked towards abolishing monarchy)
Brain evolution is quite complex since it seems the structures we call brains i.e. concentrated nerve clusters have evolved many times from ancestral nerve nets
What the ancestral functions of nerves first were is an unresolved question since neurons do so many jobs within animals.
For example while hydras are morphologically quite simple their nervous systems have been shown to control immune responses in addition to coordinating motion, what is more unusual in hydras and other hydrozoans however is that it appears that rather than using chemical gradients organized by HOX gene clusters to coordinate body alignment they control body alignment directly via their nervous systems without another chemical intermediary.
No one knows for sure how the brain developed, but it's thought that eyes came first, then the brain developed around the eyes as a way to process what they saw. At least in vertebrates.
you do know that is very old right? Most animals have that
Never thought about it. Thanks for the info.
I'd like to see a segment on the evolution of the brain. Not the human brain alone but all brains, the development of the organ itself.
I've never grown out of loving paleontology and I never will. Thank you for posting!
It would be interesting to expand that study outside of vertebrates, see what else might react to sour - it wouldn't surprise me if it's older than that, and something that was common to much of the evolutionary tree, as even single cells would probably want to stay away from acids.
Now that I’ve seen this, it kind of makes sense. First Sour, then Spice, then Sweet, and then you got Bitter and Bland coming in at the end. This is just based of whenever you taste fruits, for me primarily Mangoes and Citruses. Notice how it’s a sting, then sweet, then the sourness, when you go for a bite or sip on it, more so on Citruses (Lemon, Limes, etc) In mangoes it’s more noticeable when you’ve had the same fruit in two stages the unripe sour or bland green, and the ripe/overripe sweet or tangy yellow.
Babe wake up new Eons post
This is making me crave sour in a dangerous way
Another gem from PBS Eons, even if it's a bit sour....
The delivery energy from the presenter is on point.
Though we lost the final step in making our own Vitamin C, our bodies still produce the immediate precursor to it, L-gulonolactone. I'd like to see more study done on this ester to determine what advantage is provided by losing the ability to produce acsorbic acid (which, contrary to parsimony, guinea pigs ALSO did)
Parsimony isn't the only answer to all of biology, but is one of the most obvious by it's reasoning. Guinea pigs loosing the ability to make vitamin C could have been because they may have faced similar pressures as our primate ancestors.🤷♂️
@@sion8 Yes, when two unrelated species develop the same adaptation, it's called "convergent evolution".
@@jansenart0
I know I'm familiar.
It's not really contradictory to parsimony, it's just a matter of what the most parsimonious solution is. If you look at 20 species and two of them have a trait, and the other 18 don't, then it probably was convergent evolution. If 18 of them have a trait and two don't, it's more likely that it evolved once, and was lost in two lineages. Basically whatever involves the fewest steps is most likely.
I just got into fermenting food so this was fascinating and timely. Thanks for this video!
This was a very tastefully-done video.
Glad it didn't leave a bad taste in your mouth!
Lol that was a good one.
what's crazy about this is sour maps to the pain regions of the brain, while all other tastes map to a "taste" region of the brain. While my neuroscience class was hypothesizing why, I remembered this video!
Maybe our fish ansestors actually were drawn to the acid because their food liked it and it helped it find that. And remember, there r different levels of sour so its still protective to us. Like dangerously rotten food has a whole different sour taste, and smell, than a lemon.
Thank you, pbs eons, for keeping our thought processes’ lights on, sour jokes notwithstanding😎
This is really cool!
The early sourness of acidic water sounds more like smell. Though what is the difference between taste and smell anyway
In humans, taste warns us we ate something bad, smell warns us we are near something bad
Smell also affects our perception of taste. 👅
I have the same question. Hope this gets answered by someone qualified!
smell and taste are very closely linked, at least in humans. they are quite similar senses, both detecting chemicals. it wouldnt surprise me if both share a common evolutionary origin
Taste is sweet, sour, salty, bitter, and umami. These are detected by receptors on the tongue. Smell is detected by scent receptors inside the nose. These have a significantly wider range and include floral, minty, earthy, etc scents.
Excellent episode, thank you!
This was really interesting!! I love sour/acidic foods!!
I'd not even really thought about the evolution of taste before, but of course it would have to be selected for like everything else. Really fascinating episode!
Awesome! Could you do a video on the story of crests on Parasaurolophus and other hadrosaurs?
This was a cool episode dudes. The evolution of taste. Thanks!
Can we turn the gene to create the vitamin back on? If we do, what issues may arise from it?
Cool question! So often, we don't need the genes that get turned off.
@@Neenerella333 In turning it back on through gene therapy, could a vitamin c deficiency be a problem of the past? Though, would individuals who recieve the treatment become adverse to sour foods?
@@andrewbeeco967 I don't know that they'd necessarily develop an aversion to sour foods. Part of the reason people get away with recommending vitamin C for _everything_ is that our bodies can get rid of excess fairly readily. So while overdosing on other vitamins can have severe side effects, too much C will probably just end up giving you more acidic urine.
I remember the first time I saw Haikouichthys on Walking with Monsters in my little condo. ahh, the nostalgia...
nice video, really enjoyed it
Aye very funny
dude it was just uploaded
Bruh the video came out 30 seconds ago
Lol
Anyone else's mouth start watering through this whole video?
This resoning seems quite finalist to me. Is there no molecular or developmental explanation to explain the robustness of sour taste among vertebrates? Most importantly, is there any other living being that is not a vertebrate who can taste sour?
Involuntarily salivating just watching opening shots of all those low ph foods!
Watching this while having some vinegar, I wonder who stuck around fermented alcohol so long it went bad to be vinegar.
This is great for my run. Thank you 😊
I'm not sure about all cats not being able to taste sweets, I had one that loved sweets, if I was eating a cake he would jump right into my plate and then eat the whole slice from the ground, and he never did that with any other food! He also didn't liked cats food in general though, and would prefer human foods, like soups, stews, and, of course, grilled meat. Wouldn't eat any raw meat as well.
It was probably tasting something from the flour
Or your cat had a mutation that let it taste sweet also you shouldn’t let cats eat anything with veggies or fruit in it cause they are carnivores nor Omnivores or herbivores you should only give them meat
And cat food
I’ve been loving the podcast!!
The oldest and best -- I love sour foods! I can easily see how it'd be useful for an animal that can't make its own vitamin C. Still seems odd that it didn't go the GULOP route in any other vertebrate, though ...
04:21 -- Spots mean it's a baby deer, antlers mean it's an adult, argh my brain is confoozd!
Axis deer! There's also fallow deer, and a couple others
What's a GULOP?
@@cmelton6796 It's the typo-ridden gene we have that used to code for the making of vitamin C before it mutated. It just seems strange that it was important enough to keep hanging around for animals that can make their own vitamin C.
This is so interesting. A lot more interesting than I expected. I thought it might have something to do with vitamin C but I never imagined it would have to do with fermentation
I'm really happy that you used both "umami" and "savoury" as synonyms, rather than also acting as if we've never had a word for the flavor until a Japanese scientist identified it.
It's not one of those big issues regarding international word borrowing, but it's just always been strange that the flavor that English already has for meats, most mushrooms, and other... well, savory things has been getting shunted aside in favor of a foreign word that describes meaty, mushroomy-type flavors
I dunno about every language but I wonder if umami caught on because other languages didn't have a word for it. For example, in Spanish people use umami to mean 'savoury' because the closest words in Spanish (that I know of) are 'sabroso' which means 'tasty' and 'salado' which means salty.
@@origaminosferatu3357 It could be that, though I'd still wonder why English speakers seemed so eager to ditch the pre-existing synonym. It may also be that "umami," being officialized in chemistry, is supposed to be a more so-called proper word, whereas "savory" is more a word for the masses. The scientific fields do get weird about language every once in a while.
It is interesting that Spanish doesn't have a common word for it. With it being one of the five or so base flavors, I assumed that every language had a word for each one. I guess it's another example that language is the view of the people that speak it, not a mechanical thing
@@remen_emperor I could be wrong, that's just what I've gleaned from two years living here.
But if I've learned anything about languages it's that they're anything but mechanical.
This really does make sense when you think about how we tend to only enjoy sour foods when we expect them to be sour. If a food surprises us we tend to be unsettled and hesitant to keep eating it, versus something we already know we can eat without consequence or threat of danger.
I would argue that the ability to sense sodium an thus, to perceive salty taste, is far more ancestral. Being crucial even for invertebrates and single cell organisms for basic cellular functions, it must have been the oldest taste..
Organisms that are immersed in sodium would not need to sense it.
@@brothermine2292 if it turned out Salty was the oldest taste, then your point would be irrelevant.
@@lyrimetacurl0 : My point was that salty is unlikely to be the oldest taste. From the very beginning, ocean life was immersed in salty water, and thus had no need to seek sodium (or potassium, or other elements in seawater).
@@brothermine2292 well, that's exactly the point.. when you are in an environment that is very rich in osmoticly active ions, and you are an organism that is extremely sensitive to changing osmotic pressure and also utilizing the same ions for many living functions, be sure you'll need to be able to detect said ions and their concentration around you.. not for nothing most any form of living cell is equipped with Na pumps.. btw, idk if you actually watched the video, but according to them, the presence of acid in dangerous quantities brought about the advantageous ability to sense it, why would you think it wouldn't be the same for other bio active ions?
@@brothermine2292 in fact the very idea that the presence of something exclude the need to be aware of it is baffling to me.. there is no other reason to evolve the ability to sense something... organisms that don't get a certain stimulus don't waste energy on building sensory apparatus to detect it.. basic fact of evolution..
this is absolutely fascinating. thanks.
Great stuff. But I would also love a more in-depth video about the earliest chordates, like Pikaia and Haikouichthys.
Did anyone else’s mouth water watching the clips of sour food? Like you were about to gobble a warhead candy?
Thank goodness sour was associated with danger now I can make the excuse that I’m weak to sour candies because my primal instincts came out extra strong 💪🏽😂
You ever think about how confused the first animal to have suddenly developed this whole new sensation must’ve been
One would think that's obvious. It's just pH after all. Trivial to detect. Similarly I would bet on saltiness being the number 2.
Now bitterness is much more interesting
She does an excellent job as a presenter, and has a nice sense of humor too. Great job.
And I’m guessing air is the oldest smell
Regular air doesn't need to be detected because if we need it, then we don't need to look for it because it's in great abundance; and if it's bad for us, there's no point in trying to avoid it because it's everywhere.
"smell" isn't really a sense. It's just another way to taste. So the oldest smell is also the oldest taste.
It's really cool to see the proposed evolutionary story of an ion channel (OTOP or otopetrin) initially revealed as playing a role in maintaining the pH in the semicircular canals, the utricles and the saccules! (pH in these balance-sensing inner ear organs are critical to maintaining the small calcium carbonate stones/crystals!)
The Devonian had the highest c02 levels in history of the world
Even more than Ordovician?
Those little protofish are so cute, I'd love to have one in an aquarium and watch it suck up it's food with that little mouth.
How come evolutionary psychology used to explain other species behavior
That was oddly fascinating! Definitely makes sense…
last LMAO
Hahaha nice
Get a life @habib diallo
I’m two years towards degrees in sociology and economics and watching stuff like this makes me have second thoughts. How fascinating
First comment!!!
Get a life
I first read the title as "Why you might be the earliest taste" and I gasped! Lol