Primates vs Snakes (An Evolutionary Arms Race)

The Snake Detection Hypothesis proposes that the ability to quickly spot and avoid snakes is deeply embedded in primates, including us - an evolutionary consequence of the danger snakes have posed to us over millions of years.
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References: docs.google.com/document/d/1D...

[@eons]

If you want to learn more about the arms race between primates and snakes, check out this new paper about the evolution of primate resistance to certain toxins in snake venom. It was published while we were working on this episode! bmcbiol.biomedcentral.com/articles/10.1186/s12915-021-01195-x

[@highfive7689]

Great fun this episode. Thank you for including this paper. Stay safe and well!

[@kendomyers]

I was walking along some train tracks outside of Albany, New York. I got the sense to look down and saw a snake between my feet (probably harmless). I swear I levitated

[@likebot.]

You seriously called this an _arms_ race? Big LOLs thurr, bruh.

[@Robban.D.Jonsson.]

Are there any similar hypothesis regarding our reaction to spiders an insects?

[@machetedonttweet1343]

Yeah well, when I hike, or fish in the Carolinas, carry a "snake charmer" . Which is a .22 ,or .310 gage ,single shot, shotgun ,just for those critters, especially the copper heads ,and moccasins. But now that the invasive, "Rock Boas" are moving north from Florida and Louisiana, thanks to climate change. I might have to up grade to a .12 gage. And I retired here from NYC.

[@KRJayster]

I would say that, technically speaking, primates have definitely won the “arms“ race with snakes.

[@wesleythao8474]

🐐 comment

[@leejuicy]

We've also managed to have a few "legs" up over the snakes.

[@maxpulido4268]

@@leejuicy Sorry, Lee. I'm going to have to write you up for that one. Terrible.

[@maxpulido4268]

@@wesleythao8474 and you! Don't encourage them. You know better!

[@leejuicy]

@@maxpulido4268 Oh no Max, that's very cold blooded of you..

[@whangadude]

Lived in New Zealand my whole life, we have absolutely no snakes at all here, yet I've still been frightened by snake shaped things in the grass out of the corners of my eyes on occasions. Glad to know it's a hardwired thing.

[@theelderlardrider2425]

glad to see im not the only one thats afraid of snakes in nz

[@andovan6264]

this just makes so much sense when put together. Why would people who have not "experienced" snakes, fear them?

[@jk-gb4et]

@@andovan6264 media?

[@maxpulido4268]

@@jk-gb4et no, cuz you can put a long cucumber up to a housecat and it'll panic. You don't need hollywood to be averse to snakes.

[@maxpulido4268]

@@jk-gb4et Plus I was never afraid of snakes, but when I stepped on one and saw it wriggle and bite at my jeans, me I instinctively jumped and danced away. Got bit by a dog once and never jumped, iust pulled my hands away, and fended it off. Never been afraid of dogs either. Still love em. I think some responses are just instinctual.

[@AdamTehranchiYT]

Didn't know that venom spitting was (in evolutionary terms) a recent innovation. Also, the arms race is still on going rattlesnakes are loosing their iconic warnings since humans overreact.

[@melissapyle7879]

Yea.. i recently learned that too.. im in the south, so kinda scary to imagine.. but very interesting..

[@Carnophobe]

I heard a while ago on a forum where this came up that Native Americans used to kill the silent rattlesnakes, rather than now where people often kill the ones that rattle. That was probably a better policy ^^

[@maklu7935]

Wow, that's pretty fascinating. I hadn't heard about that before.

[@zippyparakeet1074]

​@@Carnophobethe people of the land are always smarter than the dumbasses from "civilised" cities.

[@zorkmid1083]

I heard it was because of people who hunt rattlesnakes do so by listening to the sound.

[@MrJethroha]

I feel like lots of animals feel this way about snakes. I've seen horses, pigs, and cats absolutely freak out/attack snakes on sight, and even just vaguely snake like shapes trigger them.

[@keion_arknights]

Venom lets you punch up weight classes, so it makes sense for all sorts of animals big and small to be wary of them.

[@maxpulido4268]

If you leave a piece of rope or cord near chickens they will absolutely destroy it lmao

[@andrewsuryali8540]

They're probably kinda pissed at us for creating spitting cobras.

[@amayakhler1551]

@@maxpulido4268 chickens don't count. they were god's mistakes. absolute menaces. we should be absolutely grateful they're nothing bigger than knee height.

[@maxpulido4268]

@@MrNicoJac they also will eat any bugs or mice they find

[@devilslamp7306]

That sensible chuckle when he says "danger noodle." This man is a treasure.

[@nickclement6274]

I adore him

[@slashbert]

They left out some really awesome findings about spitting cobras. Like their ability to predict where a target is heading and shoot where it will be, like a trained sniper. Or how they seem to recognise faces and eyes, so they won't just spit at any old object and waste their venom.

[@sandal_thong8631]

That would be an interesting experiment. Show spitting snakes pictures until they recognize faces and spit!

[@redslate]

This must also apply to cats as well. There's any number of reaction videos showing cats encountering vaguely snake-shaped objects (including cucumbers).

[@Bacteriophagebs]

Cats have a love/hate relationship with snakes. When they crouch, flatten their ears, hiss, and lash their tails, they're imitating a snake. It's like they know that snakes are one of the few animals that larger animals fear, so they pretend to be one when threatened.

[@leowright2885]

@@Bacteriophagebs animals are actually so fascinating. Like that is so interesting MAN ANIMALS ARE GORGEOUS

[@fruitpigenthusiast120]

The cats are not scared of the cucumbers but rather that something has managed to get behind them without them noticing

[@Bacteriophagebs]

@@fruitpigenthusiast120 No, it's the snake-shaped thing that "snuck up" on them. If you put something else behind a cat, they won't care.

[@redslate]

@@fruitpigenthusiast120 Nah, if that were the case a ball/toy would trigger them as well. The size/shape is definitely relevant.

[@dafttool]

I saw this in action in real life. At the zoological park I used to work at, we bottle raised an orphaned baby rhesus monkey. We also had a stuffed rattlesnake in our office. The baby rhesus was TERRIFIED of the stuffed rattlesnake the instant he saw it, even though he had zero previous experience with snakes. We eventually had to put away the stuffed snake so he wouldn’t get freaked out by it.

[@shrimpisdelicious]

I wonder if this is also why snakes end up playing huge roles in many different mythologies around the world. There's Apophis, the giant snake who continually battles Ra, the feathered serpent in Meso-American mythology, and the snake who tempted Eve in the Garden of Eden, to name a few.

[@donhillsmanii5906]

Don’t forget Jormanguund the World Serpent from Norse mythology

[@lina.998]

you're right.. Jǫrmungandr in Norse mythology is another famous one that just came to my mind. As well as both Python and Medusa in the Greek one

[@FirstDagger]

Don't forget Ouroboros the serpent of time eating its own tail, and the fire breathing in dragons might be a misrememberance of venom.

[@juliocasim4330]

Don’t forget the talking snake 🤣

[@1509hk]

and boitata from tupi-guarani mythology

[@phillyphilly2095]

Living in trees probably was a stronger cause of primates' excellent vision. Especially depth perception. Miscalculating the distance from one branch to another would usually have fatal consequences. Although some contemporary primate species are now terrestrial, all of them were arboreal in the past.

[@thomasparkin259]

I reckon they were probably compounding pressures that encouraged similar results. An Ape who was bad at picking out specific features of long thin things either fell to their death or got eaten bitten by what they thought was a stick.

[@littleredpony6868]

@@thomasparkin259 yeah I do agree. And not to mention our diet helped shape our color vision as well. We needed a way to distinguish between the fruit that was probably poisonous from the fruit that wasn’t

[@tannercollins9863]

So are snakes 🐍

[@Freefall347]

Squirrels live in trees too though, and they get around just fine while still having eyes on the sides of their heads.

[@lewisw3436]

Depth perception is also really great for aiming at prey when throwing or shooting things at them. This would probably have been a highly selected for trait in early humans

[@AT-AT-AT-AT]

That explains the fact that almost every ancient culture has the figure of the dragon in their mythos. The dragon being the mix of our historical main predators (snakes+birds+felines).

[@arta.xshaca]

birds? I think you meant FEW GROUPS OF BIRDS

[@sorrenblitz805]

@@arta.xshaca does that really matter? They're an old evolutionary adversary of ours and it makes sense that it would shape our minds into making up creatures that are like all of the things that used to us put together and turned up to 11.

[@Matthew-ks8fm]

@@arta.xshaca Yeah birds of prey….

[@zippyparakeet1074]

​@@arta.xshaca predatory birds such as eagles and vultures went for our babies and young ones.

[@nathanjora7627]

I’d agree with the serpent, but as far as I know that’s just about the only consistent pattern, few if any dragons outside of a relatively recent version of the European dragons, were more than just big serpents (which is the etymology of dragon). I suppose flight would also be a consistent pattern, kind of, except not really. If you look at things with a broader perspective it’s not that just about every culture has a dragon in any sense like what we mean when we think of dragon (a bat ; not bird ; winged lion bodied snake headed and tailed animal), but that basically all cultures had monstrous serpents in their mythos, and you can sometimes find big serpents that have some of the iconic features of the European dragon, usually flight, but even then it’s not through wings usually, let alone bat wings.

[@elliottcoleman8225]

I actually did see a snake while on a trail, and this explains my extreme reaction to it haha. I love snakes, and no snakes really scare me at all. This one however, which was a harmless ring necked snake, slithered just under my feet while I was working on the trail. As soon as it entered the corner of my eye, I FREAKED out. It quickly went under some cover where I couldn't see it, but once the shock wore off, my curiosity took over. I don't really understand why I freaked out so badly, but maybe that snake was just enough to push my little primate snake alert button in my brain haha

[@basantprasadsgarden8365]

Do you know, once I was searching for some plant in my nearby park, I was just walking on a trail , looking for what I was searching for, and suddenly my eye fall upon a Old skin of Snake, which it may have removed about 5-10 days prior, and on seeing this, I fearked out and ran back to the path I had came from,to my friend who was carrying a stick. Then I took that stick, and moved that skin for seeing is it alive,or not😅😅😅 like an idiot

[@sliiiin]

i almost stepped on the venomous snake while walking in the forrest. I was surprised with my nearly automatic reaction. I jumped to the side while still processing the information in my brain

[@theshinken]

Last year I was working on our pond in the garden when suddenly the resident ringed snake slid right across my gloves in the water and tried to hide in some rocks. Although in comparison I was a giant ape facing no potential harm whatsoever from a tiny ringed snake, I was equally in shock as the poor little thing. I remember my heart racing minutes after, being unable to continue to work for half an hour.

[@kinoko6096]

Once on a hike I nearly stepped on a massive rattlesnake. I love snakes and other reptiles in general but I screamed when I noticed it. I was shaken up for the whole walk back to the parking lot!

[@unm0vedm0ver]

One time I ended up accidentally straddling a baby rattler while I was off trail looking for a spring I knew about out in the forest. When I stepped through some trees to take a look around to get my bearings I looked down and saw this straight, stiff, little rattler, between my feet. It was probably just a foot long. I backed up slowly and then I stupidly poked a stick in its direction because I'd never seen a rattlesnake so straight and stiff like that, and of course it coiled back. An interesting experience for sure, especially seeing the defense mechanisms of a baby rattlesnake.

[@planescaped]

I have one of those segmented wooden snakes with cord running down the middle of them, every time I put it on the ground in front of my cats they jump up, ears back and go into danger mode. Very few snakes where we live, and none of my cats have ever seen one before, yet they react to a believable looking toy snake in a very distinct way. A kind of curious dread and fear response that is a lot different than the confused rage potatoes with 4 toothpick legs left in unexpected places gives them. Methinks its more than primates...

[@davidfoster5561]

I actually thought something along those lines too. Like it's possibly further back than just when primates split. It seems like it could be a mammal thing in general. Or at least among the mammals that were better able to adapt and possibly had more of a need. Perhaps it shows through primates better than other groups because we turned the tables on them so to speak?

[@RamonChiNangWong078]

I also notice that with a wild bird when it saw snake, it chirp like mad.

[@jcortese3300]

There's an old video on YT called "Snooky and the metronome" of a spooked cat smacking a metronome, and it often makes me think of a video I saw on a nature show of an African wildcat smacking a cobra. The metronome was even somewhat shaped like the head/hood of a rearing snake, and the cat did indeed react as if the thing might pose a threat.

[@jonesnori]

@@RamonChiNangWong078 Alice in Wonderland has a bird complaining about snakes, right?

[@JRockySchmidt]

Cats vs cucumbers agrees

[@CavemanSynthesizer]

I'd really like to see an analysis done on the co-evolution of snakes and ladders.

[@DinoJake]

Has someone repeated this experiment with spiders? Given how common arachnophobia is, I'm wondering if a fear of spiders is as instinctive as our fear of snakes.

[@sjonnieplayfull5859]

I heard about experiments that included snakes, spiders, and a few other crawlers. Anything nasty was picked up faster. Just curious if it goes for big birds of prey and lions as well...

[@squiglemcsquigle8414]

​@@sjonnieplayfull5859doesn't count for big cats. We are quite bad at spotting big cats. But we are better than most other mammals.

[@sjonnieplayfull5859]

@@squiglemcsquigle8414 so sabertooths were not that big a threat, appearently

[@Krankenwagen571]

Mark my words In future the human brain will be hardwired for fear of cockroaches and rats 😤

[@lucasb9285]

​@@sjonnieplayfull5859or they hide canoflagues them well

[@blackdragonxtra]

Even more mysterious, the ability to teleport short distances when you realize a snake is there.

[@kanrup5199]

uh, you mean jump? :p

[@moedictatornoriega8475]

@@kanrup5199 no, teleport like literally

[@melvinshine9841]

Venom spitting evolving as a specific counter to hominids could explain why that same adaptation never arose in snakes in Oceania or the New World. Snakes in those areas have had to deal with humans for a far shorter amount of time.

[@gyozakeynsianism]

Also, the snakes in Oceania just know not to mess with The Rock.

[@planescaped]

@@gyozakeynsianism Tama Tonga ain't afraid of no snake.

[@gaz-atollahofrockandrolla7519]

@@planescaped snakes are afraid of Tama's dad!

[@zeraus.w.0512]

Spitting venom has never evolved in New World venomous snakes because the dominant venomous snake family in the NW are vipers, and their solenoglyphic fang architecture does not permit the shooting of venom. Note that the spitters are all cobras from the family Elapidae, and the NW's elapids consist primarily of the very secretive and fossorial coral snakes. There is no need for the NW elapids to shoot their venom. But the NW vipers, however, have arrived at a defense mechanism that is thoroughly different from the OW elapids: rattling their tails.

[@melvinshine9841]

@@zeraus.w.0512 I don't think it's completely out of the question for vipers to have evolved the ability to spit if environmental pressures had deemed it "necessary". You do bring up something else I've wondered about, that being why rattling is only a New World thing.

[@iainclark8695]

I occasionally encounter adders at work and I definitely notice how quickly I spot and react to them compared to any other camoflaged animal. It's an uncanny feeling that the freeze response happens before I even consciously process the fact that it's a snake. What a wonderful thing it is that we can actually directly experience the adaptions this video is talking about. I love seeing them and have no fear of them, but it's instant freeze, assess and back off every time.

[@Hibernicus1968]

I think the reason that phobias about snakes and spiders are among the most common is that because these are both often venomous creatures that are among the most likely to be blundered upon by unwary humans, with deadly consequences. If you're not careful where you step, or where you stick your hand, you might get bitten by a venomous snake or spider. I think that this is why no other animal in nature seems to evoke a visceral revulsion among so many people.

[@Ws6er97]

I do a little hiking in Southern California. I've spotted a few healthy rattlers over the years. It's almost like being in a cartoon where my legs respond to different stimuli than my brain. I've consciously determined that I want to observe the snake (from a safe distance) while my hips and legs turn and walk in the other direction. Great video!

[@WlatPziupp]

So polite of them to just straight up tell people that they're nearby and want to keep their distance

[@SageofCancer]

@@WlatPziupp Until they start using it for strategy

[@Agent_A_Graham]

I've heard about all the myths of humankind revolving around snakes. Snakes are such a well-known danger to humans that snakes make a prominent trope for antagonists, even today. Snakes are like our evolutionary siblings, in a way.

[@doomsend8999]

Your not wrong, based on one theory of evolution we are all family, just really distant. (LUCA)

[@inocent007]

Yeah like chickens. They used to eat us, now we eat them.

[@arta.xshaca]

@@doomsend8999 not luca, wtf?! It is last Amniote ancestor

[@arta.xshaca]

@@inocent007 their ancestors probably hunted at day while we were active at night so probably not.

[@juliav.mcclelland2415]

Yeah, contrary to what he says here, we HAVE thought LONG AND HARD about how *this* particular predator shaped our evolutionary history. For thousands of years, we've blamed snakes for making us the way we are!

[@HAROLD-CORE]

I love that people are still doing testing like this. I am always amazed at the primate reaction to snakes. No matter the continent, primates always behave the same. My experience with prosimian reactions to snakes is limited, but I seem to remember the same thing from my visits to new world countries in my youth.

[@BladesDark]

I remember watching a show where they showed monkeys going crazy in fear just because a python was slithering in the area slowly choosing the tree to climb to reach them, I also find it wierd that some people have a random fear of said snakes.

[@pjenestratsienatie1876]

Me who owns a rattlesnake

[@ameliaroberts6859]

@@pjenestratsienatie1876 same 🤣

[@jackchellew8441]

Hell even human babies react to snakes!

[@amarketing8749]

@@BladesDark They say humans are born with 3 innate fears/natural instincts 1) fear of spiders 2) fear of snakes 3) fear of heights: but I think this one is really a fear of falling. After all if our ancestors were up somewhere high, they were probably trying to get away from something trying to kill them. You would not want to fall down into the jaws of a waiting predator. Anyway, these 3 basic fears/natural fears can become extreme, especially when triggered at an early age.

[@tarqu1no39]

Living in the UK I don't really come across snakes very often. The one time I saw our only poisonous snake, the adder, in the wild, I was already three feet in the air before my brain had even cognised what I saw! The effect was literally instantaneous and made me laugh out loud because I knew exactly what had just happened - it wasn't me that was jumping, it was millions of years of evolution!

[@scy1038]

If someone would have told 7th grade me that i would be in my late twenties watching PBS videos on my days off work, i would have laughed in their face. But i cant get enough of these vids. Please keep them coming. 🤘

[@arthurmalvavisco8739]

I used to work with venomous snakes. As a biologist in training, I always loved snakes and other reptiles - I find them misunderstood silly critters. And Yet, working up close with rattlesnakes and lanceheads, I would frequently find myself mesmerized, near paralized, by the uncanny beauty of the largest specimens. By their unblinking eyes that so frequently looked like molten star cores. I worked daily with over 400 snakes for 3 years, and sometimes my heart would race as if it were my first time. Yes, I love them and they indeed are silly little critters, but instincts are a powerful things, and we humans certainly got them.

[@alecburris4225]

Often when chimps find a large snake they alert their whole group then they all gather around at a safe distance to observe it for long periods of time

[@MelGibsonFan]

I’ve never been able to explain my revulsion towards snakes but I think venom is a big part of it. The same way we’re wired to avoid brightly colored creatures, I’m terrified of venomous snakes, however this fear is non existent when it comes to small constrictors and Gardner snakes (which I learned after playing with one for a long time have mildly venomous saliva and pretty smelly musk).

[@motherlandbot6837]

@@MelGibsonFan Garter Snakes have functional Duvernoy's glands, and like many colubrid snakes long considered to be harmless to Humans, are now known to be "mildly" venomous. I routinely caught and quickly released them as a child; as you noticed, they initially defend themselves when grasped by striking and biting, and by smearing a mix of anal secretions, feces, and urates on their captor. If they are not released promptly, they will shift from repeated bites to focused "chewing" on their captor, and this is when envenomation actually occurs.

[@krishanuA]

@@motherlandbot6837 Excellent insights. Thanks, fellow user. You clearly are not a Bot!

[@ricnyc2759]

Please follow the part of your instincts that find them dangerous.

[@philosophicalfishtanks1575]

Once froze up for like 10 seconds at a local lake because I was CONVINCED the thing I was looking at was the hood of cobra... spoilers: I live in northern Canada and it was a rotten swamp lilly. I'm still struck by how completely irrational and overpowering that feeling was, it was like my brain couldn't process it logically. Only after I realized it was plant did I realize how insane the initial assumption was... instinct is one hell of a drug.

[@sam1yoo0ell0]

Never saw a snake in the wild before a family holiday in Sri Lanka. At that time I was a teenager and felt invincible and did not scare easily. I’d always loved snakes and spiders and would beg my parents for one although they never let me. In Sri Lanka, we were walking to an archeological site and were about 4 hours from the nearest city, and had walked about an hour from the car. As I was walking in my sandals, something came over me and I jumped as far as I could forward, looking back to see a small snake slither away right from where I had been about to set my foot. I hadn’t been aware of seeing it before jumping, but something innate had made me avoid stepping on it with my foot exposed. One of the locals had seen this and started praying and told me that it was a krait. Kraits are apparently highly poisonous and can kill within 4 hours. As I was about 4 and a half hours from any large hospital I could well have died. I knew it was either a mad innate instinct or divine intervention. Thankfully this video has told me why this happened 10 years ago.

[@Kokorocodon]

Fascinating story. Instincts are a useful thing.

[@alhypo]

It's worth considering how colorblindness might also be related to our co-evolution with snakes. We tend to think of colorblindness as a disadvantage. But it's actually a superpower in many ways. Colorblind people have a much easier time seeing patterns such as the camouflage scales of certain snakes. So it would have been advantageous for the overall survival of the tribe if a few of its members had an extraordinary ability to spot snakes from a distance and warn others of them. We may owe a rather large debt to our colorblind ancestors. And how did we repay that debt? By making red and green the standard traffic signal colors. The two worst colors for the most common form of colorblindness.

[@alex0589]

any source for that claim?

[@alhypo]

@@alex0589 Nah, but you can Google stuff. As a personal anecdote, my buddy's stepdad served during the Vietnam war. But he ended up working in intelligence because he had an uncanny ability to spot camouflaged enemy encampments from aerial surveillance photos. He was able to see them so easily because of his colorblindness. The camo patterns were very obvious to him whereas everyone else just saw jungle foliage.

[@dandywaysofliving]

@@alhypo I wear yellow tinted sunglasses, and I can legit see which plants are greener and well watered. I freaked when this first happened and I took em off to realize I couldn't spot the difference without the glasses. So if someone is color blind. I can imagine what the camo probably looked like compared to the plants around em.

[@jordanm1526]

If color blindness was evolutionarily advantageous for survival, the genes for color blindness would me much more prevalent in the population. The fact that color blindness is exceedingly rare demonstrates that our non-colorblind ancestors had the survival & reproductive advantage.

[@alhypo]

@@jordanm1526 It's not exceedingly rare. About 8% of men are color blind. You have to keep in mind that humans are pack animals. We do not live in isolation. We live in tribes. And the overall survivability of a tribe is increased when members have different skills and abilities that can be applied to benefit everyone. One such skill that colorblind men often have is easily spotting animals that are well camouflaged. A hunting party will benefit from having a small percentage of its members who are able to spot things others in the group cannot. So it makes sense that a certain percentage of men have this trait as opposed to no one having it or everyone. And this is a proven ability. My friend's stepdad was assigned a specific job during the Vietnam war because he had the ability to see things people with full color vision could not. It certainly increases his survivability during the war. It was such a valuable skill that they didn't want to risk putting him into open combat.

[@amphicyon4359]

Pretty funny that ranged weapons are pretty rare in nature (land vertebrates especially), but once humans got the ability to kill snakes at a distance, almost instantly snakes get their own too! (multiple times). Immediate arms race in an unexplored field just to combat a specific family

[@unvergebeneid]

So coming up, the sniper cobra!

[@TheSpeedReaper]

Wait a minute... Does that mean the Cobra will start calling itself Solid Snake?!

[@suyci]

This is so wrong it's making me a bit sad. You can not speak of instantly when it comes to evolution. Every beneficial trait takes generations to develop. Just ask Castro about his milk factory plans, and that's guided evolution with a head start, not the random junk nature has got going on. Ranged weapons are also fairly common in nature. Lizards spit, Llamas spit and sea snails have evolved a ranged poison sting and some crabs even use pressurized water and birds can use their poop for aerial assaults. Need I go on? Evolution has always been an arms race, kill or be killed and all.

[@charliebaker5731]

@@suyci spitting venom is pretty rare in vertebrates though. If the cobras didn't do it it'd only be within the realm of jurassic parks fantasy dilophosaurus

[@protocetid]

someone call TierZoo

[@elizabethlowes6501]

I remember watching a thing linking spotting snakes to yawning. We still haven't got the why of yawning figured out: testing has shown no increase in oxygen in the brain after yawning, nor decreased brain temp, which are two popular theories that have been put forward. But they showed a bunch of peeps pics of snakes chilling out in leaves and rocks and other camouflage, and timed how long it took to find the snakes, and tested a different group on the same thing, but had the tester yawn at them right before showing the pics, and the yawned at group were faster at finding the snakes. So yawning may be a social signal of "hey, i'm tired and not paying attention for snakes right now", among other things.

[@twistedtachyon5877]

Yawning at people... for science! I love it.

[@The_Opinion_of_Matt]

I read this and yawned. I think I was prompted.

[@hadisoufi7752]

Tons of animals yawn though, including non-social animals like lizards

[@elizabethlowes6501]

@@hadisoufi7752 I never said that danger noodle awareness is the only reason why yawning exists, only that it's a pattern that's been tested in humans, with some degree of positive correlation. Dogs and cats and stuff yawn at each other all the time after a stare-down as a way of diverting aggression and being a little submissive, no snakes involved. Heck, the other day I watched my own snake yawn when coming out his cave. Lots of reasons to yawn, and one of them might be snakes.

[@mirahshay1833]

I know yawning is a sign of stress in dogs I wonder if its actually the same for us and puts us on higher alert

[@kayzeaza]

Stuff like this is so interesting. Just millions of years worth of adaptation being built on each other.

[@Tricks27]

Hey Eons, it would be interesting to see the evolution in how both canines and felines developed the means of picking their cubs up by the neck to transport them elsewhere.

[@tonatiuhnino3711]

Snakes: I don't have arms Primates: I missed the part where that's my problem.

[@Mikailodon]

At least I’m a komodo dragon so I’m kinda safe

[@bob1234881]

Wow. A Komodo dragon. You have my respect. 🙂

[@KarnodAldhorn]

The study mentioned in the beginning has only relatively harmless animals next to the snake. I wonder what it would have looked like with snakes, lions, wolfes and spiders.

[@korth26]

You guys are a gem. Thanks for all this free knowledge. I think I'm gonna donate.

[@Xnaut314]

Primates vs. Snakes: Battle to the Evolutionary Death! Birds of prey: Love this show.

[@nosotrosloslobosestamosreg4115]

Could this hypothesis explain the huge amount of snake representations among all human cultures?

[@Ezullof]

Is it that huge, though? I don't find snake to be more prevalent than animals such as bovids, canids, felids or birds in general. Of course it depends on the place, but while there are representations of snakes in a lot of cultures, it's probably just because there are a lot of representations of animals.

[@jooot_6850]

@@Ezullof eh, there are plenty of serpentine dragons in just about every culture ever. They may not exactly be snakes but they’re close

[@mitchjohnson4714]

@@jooot_6850 Dragons are absolutely snakes. That's the thing. There is no animal form that is universally represented as supremely powerful and dangerous like snakes are. Birds may have been messengers of the divine, but snakes were representative of the power of life and death.

[@liamjohnston2000]

@@Ezullof Snakes are often featured as the villain in many cultures (Apophis from Egyptian Mythology, the serpent in the Garden of Eden, Typhoon from Greek Mythology, The World Serpent from Norse Mythology).

[@jonathanmiller5232]

@@Ezullof There are certainly quite a few depictions of snakes and if you're in the west there is a pretty clear correlation between dragons and snakes and the "snake in the garden" story.

[@CelestialSwann]

2:46 I absolutely love that art piece, kudos to all art included though

[@Petrov3434]

BRAVO - always great in content and delivery !!

[@charlotteb6450]

I've always wondered the same about spiders since it's such an immediate response for so many people to be creeped out by their form and movements lol this was such an interesting video and i love the presenter's energy and enthusiasm!!

[@oofshapedhuman4974]

My reaction to mosquitos is entirely ape brain

[@debrabiderman4275]

My reaction to spiders is total freak.

[@JaguarBST]

I don’t have any strong instinctive reaction over a spider, but unexpected snakes sighting freak me out of my mind.

[@GoldenGod69]

If it is an unrecognizable spider species or it looks dangerous I go crazy, if it’s daddy long legs i let them live

[@charlotteb6450]

@@GoldenGod69 same lol

[@CaptainChuck15]

This was one of my favortie episodes! This last summer I was out in the woods near Red River Gorge, which has a pretty sizable Copperhead population. One night I was walking back up a long the path with just a flashligt. I was shinning the light far enough in front of me to know I wasn't going to trip or step on anything. At one point I saw something in front of me, and my brain was like "what the heck is that?" I was still too far away and in the dark to see it clearly enough, but as I got closer, sure enough the snake zipped across the path. Absolutley was using my primate superpower here. I couldn't tell what it was, but my brain deep down was pretty certain it was a snake.

[@rogerharvey1698]

Ya’ know, I found this to be very thought provoking. From a personal perspective, I remember reacting very strongly, almost inappropriately strongly when I was startled to recognize a water snake coiled beneath a fishing lure I was working to unsnag from some brush lining a stream I was fishing once. My girlfriend nearly dumped the canoe from laughing so hard at my “school girl” shrieking. I’ve been startled in the woods plenty of times, by deer, grouse, elk, even a bear once, but nothing ever elicited a scream like that nearly harmless common norther water snake. There was just something instinctively triggered by those patterns and coils hidden in the grassy brush of that wooded stream. Even in the immediate time time following the incident, I found myself reflecting on the inappropriate intensity of my reaction. In my defense that was one big g*dd*mb water snake. Thanks for the opportunity to introspect further, ummm....thank you, I think!

[@georgecerda6727]

This was an amazing watch! LOVED IT!

[@clai6016]

I remember going on a run in South Korea while it was raining. All of a sudden I stopped, practically jumping up to avoid going forward. It was so sudden I was actually confused, but then I saw a skinny black snake stretched across the trail I was running on. I hadn’t even processed it before I stopped running, I ended up just turning around and making up my mileage elsewhere. This video was awesome to watch after having that experience.

[@littleredpony6868]

I had a similar reaction as a kid when I was out exploring out in the woods and came across a diamondback rattle snake

[@Freshbott2]

I’ve heard a theory that human and other primate babies have an innate stress response to predatory birds as well, and that along with snakes it could explain why dragons developed independently in almost every lore in the world, even in cultures where people wouldn’t be that familiar with snakes.

[@brianboru2762]

There's also a theory that Leopards freak us out on a genetic level as well. Hence the Western Dragon, body shape of a Leopard, Scales, head and tail of a snake, and wings like a large bird of prey. All your genetic fears wrapped into one horrifying package, and for the cherry on top, they breathe fire.

[@mitchjohnson4714]

Haha! The Mexicans have both in their national symbols and flag!

[@kanrup5199]

dragon would actually be a creature that made sense if it was a flying reptile (petersaur) that had venomous bite or spat venom (or acid). But there is no creature that actually breathes fire.

[@zlac]

@@kanrup5199 well, if you got acid spat in your face and eyes, you would run like hell and maybe feel like your face is on fire.

[@Quetsalcoatvl]

@@kanrup5199 Dragons in my culture don't breath fire, they live in underwater caves and they spit a spray of acid or gas.

[@DavidAkhter]

Awesome, I need more of this.

[@luminyam6145]

Excellent video, thank you.

[@hhjk377]

Saw Snake Detection Hypothesis live at Denny’s once. They were brutal.

[@BonaparteBardithion]

What is Denny's in this context? Because I can't imagine live music at a cheap diner chain.

[@negativeindustrial]

@@BonaparteBardithion It’s a pretty internet famous performance by a metal band in a soon to be closed Denny’s. They were pretty brutal.

[@gyozakeynsianism]

Yes, the food is really bad at Denny's.

[@maxpulido4268]

@@negativeindustrial I told them call the police if you want but I'm here to thrash and you can't stop me

[@felipereigosa96]

I was hoping he would mention how cats seem to have something similar to primates. Put a cylindrical, longish object near a cat and the moment he sees it he will jump like crazy.This behavior must have saved a lot of cat ancestors.

[@russellpeters6643]

@@MrNicoJac yes

[@pratitagriculture9686]

amazing presentation, Thank you

[@ybthr]

LOVE this video! in history you can see the effect of this "hardwiring" from dreams of dragons to our sharpened kinesthetic awareness etc

[@toasties23]

So you're telling me snakes on a plane is just the natural progression of the primate/snake rivalry

[@vasararh]

I have not been blown away by a hypothesis in a long while, but this explanation of why cobras became range units has done it

[@JubioHDX]

interestingly many rattlesnaks are starting to become silent as a response to modern humans overreacting and killing snakes on sight for making themselves known, whereas previously humans used to kill the silent ones for their sneakiness which is what made their rattles so prominent in the first place😂cant confirm that myself, but another cool result if true

[@Magplar]

You guys did a great job on this episode

[@leroyc5289]

very helpful information!

[@MrMotchel]

The first study seems mostly related to being able to spot the texture of the scales on the snakeskin in the photos, vs the body shape, but I’m sure there’s plenty of truth to the concept.

[@marcinrobak6038]

Thanks for detail.

[@Macallion]

Could the quickr identification of a snakey shape in the experiment not have something to do with the fact that they have a shape that is a lot more distinct from other animals? It's a lot easier to tell a cat apart from a snake than to tell a cat apart from a dog in blurry pictures.

[@gwendolynrm]

That plus the scales! Way easier and faster to narrow down that in it's a snake than say a specific fuzzy quadruped with a snout out of the many options out there.

[@minehermit]

this ^^^

[@ruairidhmcmillan2484]

Check the controls of the experimental design, it's not as simple as just showing people some images and their identifying them. The shape is consciously indistinguishable by design in order to allow the experiment to determine if their is a preconscious effect. Also, what do you mean by a more 'distinct' shape? What allows you to determine that shape as being distinct, whether or not it is a snake. SDH posits that Cattharine primates were placed under different evolutionary pressures, and so developed higher resolution vision and a more adept visual system.

[@tosehoed123]

@@ruairidhmcmillan2484 boooh

[@astrowyrm6871]

maybe their shape is more distinct to us *because* of the snake detection gene

[@WoodliceCC]

I've watched a couple of the EON vids now and they're friggin' awesome. Love the presenter, who I will now and forever be referring to as the 'American David Attenborough'. I hope you're American and I hope you see it as the massive compliment I intend it to be!!

[@Chrisy7]

These videos are a blessing. Thank you.

[@samstarlight160]

7:30 The little giggle over the term "danger noodle". That was adorable

[@HalfHeartedFanatic]

When I lived in a small town in Cameroon, the mere idea that there was a snake in the area was enough to summon a spontaneous brigade of men and boys with sticks, hoes, and machetes, determined to kill it. Now I live in Madagascar, where there are no venemous snakes, and people are a little bit more chill. There's no love for snakes here, but there's not the same obsession to kill any snake that shows up where humans live.

[@stefanostokatlidis4861]

People in developing countries are extremely afraid of animals in general. You can see it in comments online. Even if someone gets bitten by his own fault, they will still blame the animal and call it dangerous. They do not tolerate deaths or misadventures of humans by animals. In Madagascar people sadly are ignorant about the wildlife and hate them. Snakes are evil, geckos are evil, chameleons are evil, the aiai is evil and so on. Luckily Australia is populated by a developed nation, otherwise they would kill all the strange animals there.

[@ghufroon4134]

@@stefanostokatlidis4861 yeah cus those developed people already kill half of those developing people

[@hashmarker4994]

From a developing nation here. And Ican confirm that people are quick to kill snakes and other lethal/venomous creatures on sight. The reason being in developing nations most people living in the fringes of society has no healthcare access. The hospitals are too far or not reachable by due time. Often times incapitates the person, or disables him which can straight up destroy any income he/she brings. This along with a very limited animal rescue capabilities made it such that its a you or me situation with many predators. The empathetic outlook a lot of people in developing nations have is because of a lack of desperation.

[@stefanostokatlidis4861]

@@hashmarker4994 what about not so dangerous animals or completely harmless animals the? So many times we hear about people in developing nations killing geckos, frogs, many other animals that clearly are not dangerous. Oftentimes they believe they are dangerous or have other superstitions around them.

[@hashmarker4994]

@@stefanostokatlidis4861 if they have any value in selling or as food they are probably poached or killed for that purpose. Otherwise noone kills animals for the sake of it.

[@shenzhenpingpong]

This was a wonderful episode.

[@TheOldMan-75]

This is such a great channel for those little breaks throughout the day.

[@chrisX1722]

I once was hiking, kinda off-road when I quickly turned around, not really knowing why. Only after I went back a couple meters I realized that there was a snake. It felt like my subconsciousness noticed that there was a snake before my consciousness and made me go: nope! Get away quickly before

[@SIC647]

It did. Fear reaction is in very primitive parts of our brain, and is able to provoke a instinctive reaction in a mere 400 ms. It bypasses cortex and the frontal lobes (the higher functions that makes us human, so to speak), and causes an immediate fight/flight/freeze response. If the higher functions get involved, our reaction time is closer to 1 second. The primitive reaction is not as precise as the rational one (the stick that looks like a snake). But evolutionary it has meant better survival to be able to react quickly, even though it was imprecise.

[@YurinanAcquiline]

Interesting, when that happens to me.. I don't turn back. 😅

[@arta.xshaca]

@@SIC647 And I am thankful our ancestors evolved those. More thanks to those jawless fishes who made the "brain" in the first place :)

[@BenjaminGunnell]

Yes. I'm conflicted about my emotions towards snakes. A viper bit my cousin once, other ones swam near my pet dog, and yet another time in Cub Scouts I once cried over a dead rattlesnake. They killed it in 'our', campsite, but it did nothing wrong to us.

[@TheRuanay]

The first time I saw the picture at 5:22 was in Mrs. Johnson’s 4th grade classroom on a reading comprehension assignment in 1998. Here I am 25 years later still psyched by our hominin ancestors.

[@udonenomee2117]

For me it’s the times I step on a stick and the way it shifts in the leaves about 4 feet away freaks me out. I’ve seen actual snakes in my path before too and off to the side. There is absolutely a built in reaction, almost to the point of jumping straight up into the air. It feels like my heart jumps at least, even if my feet don’t have time to.

[@williamlazenby314]

I grew up in the Southeast USA. Any walk I went on with my dad was less about enjoying the natural world and more about how to spot dangers. That's how most people I know were raised. Snakes and poison ivy were at the top of the list. Not only was it culturally imposed on me, but apparently genetically. Honestly, what's weird is that I have always felt comfortable and soothed when holding snakes. Having a boa move around my neck and arms is more relaxing than a massage. That being said, I still jump at danger noodle shapes when I take a walk 😂

[@zippyparakeet1074]

I love this little conflict our conscious and subconscious sides have. I too love snakes and have held them many times but I absolutely jump if I spot a snake shape from the corner of my eye. It's just instinct.

[@safaiaryu12]

Same! I adore snakes, I really want to own one someday, but seeing an unexpected squiggly thing or hearing a rattle WILL make me jump out of my skin.

[@chakraborty1989]

Could you share your/your fathers wisdom regarding danger detection?

[@jasonhaven7170]

Not poison ivy. You're a coloniser, there's no evolutionary pressures that have existed long enough for you to fear poison ivy instinctly. Instead, you were just taught to fear poison ivy.

[@etuanno]

I have seen a real snake in the wild twice in my life and instantly I was wide awake and a terrified. I knew that 95% of the snakes here in Switzerland are not venomous, but my snake instinct didn't care at all. It didn't even notice me really and went its own way a few meters away from me, slithering into a bumch of leaves searching for food. Monke brain does monke things xD

[@Horizontalvertigo]

I remember almost stepping on a snake in Japan. I was like "UWAH!?" And the snake was like "UWAH!?" and slithered away.

[@Lazazia]

Well, that was an awesome episode. I want to see more about snakes!

[@tarcisomelezmartins2281]

Amazing job, guys!

[@noobkaka567]

This was a really great video! I wish you could go more in depth about human eye vision and how it compares to most other mammals or even aquatic life.

[@arta.xshaca]

I would say birds have the best eyesight: they have the most visual acuity and can see the most of the EM spectrum. We only see red to violet, they can see upto ULTRAviolet.

[@Infernoraptor]

Here's a thought: if we didn't start our cultural evolution so quickly and stuck with throwing stuff longer, maybe there'd have been an explosion of ranged combat adaptations in other groups

[@maxpulido4268]

Like what? I can imagine a deer ducking instantly when he hears the twang of a bow, or a footstep. Maybe zigzagging as they run? This might make them easier to catch by persistence hunting, though, so maybe won't work. Maybe hard cartilage plates guarding their vitals. Like wombats have that hard cartilage plate to guard the opening of their den(and their butts). But a deer having it over their entire rib cage. Maybe fused ribs? It would be heavy, but it could protect against projectile weapons.

[@RamonChiNangWong078]

imagine snakes would have developed fire

[@Ezullof]

Not sure what you mean there. Our "cultural evolution" didn't change anything about our habit to throw stuff until very recently, when we invented firearms. And even now there are still people hunting by throwing things.

[@maxpulido4268]

@@Ezullof Yeah but very rare. Basically all cultures evolved to using tools to throw things farther and more precisely, like bows, atlatls, and blowguns. Weren't the only people still throwing things by hand Australian aborigines?

[@maxpulido4268]

@Ops Blac I think the porcupine would definitely develop the ability to spray like a skunk. Or maybe develop painful toxin on their quills.

[@AffectiveApe]

great, great video... well done.

[@jasperzanjani]

this is such a great channel, I'm glad it's got millions of subs

[@jl3039]

That was one of the best episodes in a long,long time. I love danger noodles 🤩 thank you!

[@natebelcher3401]

I love how they kept his chuckle in the final cut after he said danger noodle. So wholesome

[@BrickedUpBuilds]

I love this channel for videos just like this

[@xxx_putin_has_a_flaccid_pe5374]

I feel like this is why I get startled seeing ANY snake at first. It takes a second for my brain to go “Oh, friend snake not danger noodle”

[@westrim]

I like the SDH, but do feel like it's a of a reach to assign it anything more than minority responsibility for many attributed adaptations. I think it's far more important that many of our ancestors spent at least some of their life in trees. For example, visual acuity. A primate would occasionally encounter a snake, but constantly encounter branches, and the only way to judge the next branch you're jumping to is sight - no other sense is particularly helpful.

[@garrett6064]

I don't think he said forward facing eyes were because of snakes, just that it made more vulnerable to their toxins. Nor did color vision.

[@astrowyrm6871]

@@MrNicoJac it would be necessary to identify different fruits though

[@Josh729J]

but didnt they say other primates had worse vision in places with least snakes?

[@MaryAnnNytowl]

It'd be interesting to know what might be different, if anything, between those of us who like snakes, and keep (or want to keep) them as pets, and those of us who are frightened (even terrified) of snakes. Thanks for this video, Eons! I really love this stuff! ❤❤‼️💯

[@zedantXiang]

Probably just human nature, humans tend to be interested in dangerous thing in general, not just snaked.

[@stefanostokatlidis4861]

A study like this has been made in Australia. Even humans who keep snakes are much more sensitive to snake images and can detect them faster.

[@kaloarepo288]

I'm one of the people who absolutely loathe them even on videos and in books -but I'm glad there are some people who are not so scared of them and keep calm when they are around -otherwise we would have no one to study them or breed them so we can make anti-venom and save people's lives.

[@annominous826]

@@zedantXiang Pet snakes are generally harmless, though, and the people who keep them do not see them as dangerous or threatening, but as adorable little silly kittens.

[@zedantXiang]

@@annominous826 That's what I'm saying

[@tyverymuch2094]

I love the odd ball science like this that you wouldn't normally think of

[@benhiebert6140]

Fantastic video

[@froginaboxVEVO]

Not so much of an "arms race" for the snakes...

[@grokeffer6226]

😄👍

[@westrim]

More of a harms race?

[@eugenio5774]

fascinating!! absolutely fascinating! as usual, PBS Eons gives excellent answers to questions I didn't even know I had.

[@Miamcoline]

Very cool! Good plug too!

[@Blueeyesthewarrior]

I love the little vestigial legs on the illustrations of early snakes.

[@jmartinez310]

LOVED this episode...maybe my favorite yet! Please, more episodes with theories that are not nearly definitively proven!

[@elvancor]

I'm probably getting ahead of myself, but if the way our snake detection improved was by upping our general pattern recognition, it may have made us a lot smarter in general as a side effect.

[@tylerhawley4012]

A simple adaptation that stumbles into being far greater an advantage than “intended”, I believe this is a common theme of evolution.

[@CLipka2373]

Wasn't it the snake that told Eve to eat the fruit of the "tree of knowledge [...]" in the garden of Eden?

[@elvancor]

@@CLipka2373 Yes, snakes are demonized in many places throughout human mythology. Even dragons are part inspired by snakes, sometimes poetically referred to as serpents. Strangely though, snakes have also long been worshipped and linked to knowledge and medicine (see rod of asclepios). I don't know where I'm going with this, I'm just saying us and snakes have a weird relationship.

[@salemsaberhagan]

Pattern completion items are indeed common features of IQ tests and abstract reasoning tests.

[@Blissfulbizz]

Snake in the grass

[@touchm3]

Imagine getting so terrified of a thing that you pass on that fear thousands upon thousands of generations down your evolutionary line.

[@baneofbanes]

I mean the monkeys that weren’t scared of snakes eventually got bit by a venomous one and died.

[@supahfly_uk]

I love this channel subbed

[@thedoruk6324]

Chad *Primates* versus virgin *Snakes*

[@ecurewitz]

Almost stepped on a snake this summer, the thing totally freaked me out. But snakes generally don’t bother me, unless they surprise me

[@ishaanharry8995]

7:33 that little giggle 🤣🤣 didn't stop laughing for a while

[@GaasubaMeskhenet]

in love with the use of the word "touchy" here

[@willedwards4782]

Can you start doing a land acknowledgement in the videos? I know another PBS show does them, but I think it's important to do them everywhere we can

[@BonaparteBardithion]

I believe this is the show that usually does. It's possible they didn't in the last couple because there weren't any fossil or archeological sites being discussed. In general, I agree and would like to see more shows take up the practice.

[@Scraggledust]

I kept spotting tiny (talking less then a half-inch in length) pink snakes in our yard. My family said no way, has to be worms. Sure enough, they were snakes! Baby Texas Blind snakes!

[@InMaTeofDeath]

Reminds me of the snake I caught most recently. Just a common garter I used to catch them all the time as a kid. The cool part was I didn't even realize I was looking at it at first I noticed the orange/yellow striped pattern before anything else.

[@oneshotme]

Enjoyed the video and I gave it a Thumbs Up