Why Are Periodical Cicadas So ... Periodical?

[@SciShow]

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[@Gulgathydra]

Every 221 years, these cycles sync up. That is when the cicada armies will rise to destroy us.

[@jep9092]

Do you know when the next sync up will be

[@Gulgathydra]

@@jep9092 *2219* 1998 was a hard-fought year. Luckily for us it was a La Niña year, and the cooler weather slowed the cicadas down. As a bonus, the governments were able to disguise the human fatalities as hurricane-related. With 200 years of global warming, it is anticipated they will come out of the ground the size of housecats, but move even faster.

[@martingelinas1721]

"Let them fight!" Who knows, they might compete with each other. And we might find out pretty soon. Brood XIII and XIX are due in 2024, and there will be some overlap in several states.

[@lorijudd2151]

"What are we doing tomorrow night, Brain?" "We're going to take over the world!"

[@AynneMorison]

cotton pickin' mathematician! away with the magic numbers!

[@richardpowell4281]

Michael's looks over the years are like a Pokemon Evolution. His hair continues to get longer and more luscious.

[@yazanalj1975]

It was better before with the blond/yellow strand

[@LeMAD22]

But for some reason he has no hair on his arms...

[@mcstabba]

I expect him to come out as a vocalist in a death metal band soon.

[@ConstantChaos1]

@@yazanalj1975 I disagree

[@ConstantChaos1]

@@LeMAD22 that's pretty common for someone with Native American/ Pacific Islander heritage which would look about right

[@anjulikamins6420]

Anyone else tune in too see Michael's hair? I adore everything about scishow, but I'm also here for the hair

[@yetinother]

Go Michael go! Grow that hair Grow!

[@666curse666]

I don't tune in to see it but my lord does this man have a beautiful mane growing

[@seanriopel3132]

I miss Hank

[@Shanoninoni8]

Yasss

[@pyrogriffin]

That slight widow’s peak is real nice.

[@murielvaillancourt3855]

During my childhood in France, we had a lot of cicadas each summer and their song stays in me as the best souvenir, followed by all the horse chestnuts that were falling on the ground each autumn. We picked them up and play with them for weeks, making some little animal figures with them and with acorns.

[@davidsalazar13]

Please write a book 🤩

[@atsukorichards1675]

Almost same here. In Japan, my childhood summer would have me running with a small net on a pole to catch the cicadas on the trees, and getting peed on. They are the pure summer to me.

[@Kayleigh_McKee]

Its honestly really wonderful that Cicadas are one of the most universally "summer" things that can connect people all across the world!

[@BlackIndigenousPosse]

@@Kayleigh_McKee Two countries: "UNIVERSAL, ACROSS THE WORLD!" Such is the American education system.

[@b22chris]

In Cincinnati we’re having our 17 year boom. It’s so loud it’s unpleasant to be outside. I’m talking you can be on the highway with windows up naming to music and you can still hear them. It’s wild.

[@weareorigin]

They are math teachers, teaching about division by prime 13 and prime 17.

[@jonathanlevy9635]

All nature is your math teacher, you just need to stop and look at it

[@mike79patton]

Insects don’t qualify for teaching credentials.

[@pedrolmlkzk]

@@mike79patton you'd surprised

[@lyndsaybrown8471]

Tired of being told that "the best years of their lives were behind them" cicadas evolved to spend most of their lives as youngsters. Humans do not understand this. Cicadas do not care.

[@hi5dude2]

That explains why they are so loud when they do emerge. Gotta yell about politics and the worthless younger generation while you can!

[@SaltpeterTaffy]

*laughs in 18+*

[@delliardo583]

The front of my car is covered in cicada guts. Those little bugs really love the highways.

[@maykoramirez2046]

Uu

[@francislapointe8316]

Lights in general

[@jasony25]

Could be attracted to the car sound or just clumsy flyers.

[@The-Heart-Will-Testify]

@@jasony25 they are legally blind

[@Dragrath1]

@@jasony25 They are very very clumsy fliers, they fly into everything either landing or if they can't get a foothold flopping on the ground (possibly flailing about struggling to right themselves) for a bit then get up and fly until they hit something again and the cycle repeats. They have no fear of anything no self defense they just repeat this with the males singing when a lady shows up. Smooth surfaces are probably their biggest "predators" with the cicadas trying to climb the surface only to struggle to get a foothold fall back down regain their bearings and then walk right back to try again until they either give up or exhaust themselves. I've tried helping them out but some of them just fly right back and start trying to climb the same wall again. In the end the dead cicadas start piling up.... They are so derpy but they are kinda cute too I'll miss the little guys

[@georgecrutchfield8734]

They are past their peak here in North Georgia. I could barely hear them when I went outside today and last week they were so loud, one could barley hear their own thoughts.

[@Dylan-vd6rz]

Lucky.. it feels like they exist all summer up here in North Carolina

[@Evergreen64]

The 17 year ones just disappeared over the last week here. The noise of the ones far away is weird. It reflects off things and sounds like the invasion in War of the Worlds.

[@Rem694u2]

That's a scary sound. lol

[@gapetheapegod7976]

Where? In Coleman falls Virginia we didn't get any this year

[@ThatBernie]

Growing up in Texas I was accustomed to the sound of cicadas every summer (we get the annual ones down there), in fact I always found it very soothing as I sat out on the porch on calm summer evenings. Now I’m in the DC area and people here are absolutely freaking out about the Brood X cicadas, complaining that they’re too loud and gross, and I just find it funny.

[@AnarchoLoserist]

@@ThatBernie yeah, I'm a life long Georgia resident and when I was a kid I never even considered that the noise was coming for anything haha. I just thought that's what summer sounded like

[@Evergreen64]

@@gapetheapegod7976 In Arlington, just outside DC.

[@silversam]

First time I found the molted shell of a cicada, I thought it was an alien. I mean... Still not completely convinced they aren't, but y'know.

[@BrandonRalstonUSA]

The shells are hella creepy!

[@ibuttchuglsd6668]

@@BrandonRalstonUSA I havent heard hella in years. Miss it. I miss kick rocks too.

[@BrandonRalstonUSA]

@@ibuttchuglsd6668 Or how about don’t let the door hit you in the ass? lol

[@ibuttchuglsd6668]

@@BrandonRalstonUSA talk to the hand cause the face ain't listenin.

[@kutie216]

I had a childhood friend (a girl) eat one… literally right in front of me and I was so disgusted lol. It was the neighbor girl who lived by my grandparents and I was disgusted by cicadas and still am. The shells scare me and disgust me after watching her eat it lol

[@DylanMatthewTurner]

I was driving home from college after graduation (Indiana to Texas), and my family just happened to travel into the handful of counties in Illinois where the 17 year cicadas just happened to be appearing at that exact moment. It was cool to see them up close!

[@IntrepidFraidyCat]

I've always loved cicadas. Of course, I don't live where the hordes of the red eyed ones come out. We have the cute green ones every year.

[@kdavis4910]

The annuals

[@joshuasims5421]

My question is, how do they manage to come out after exactly 17 years? Do they just have a very reliable life cycle? Or do they have some biological mechanism to wait that exact amount of time before emerging? This may be one of those unanswered questions...

[@harismohammad2005]

Ive read that they feed on the sap in trees and measure seasonal changes and so years using it.

[@MiamiPush2theLimit]

Time periods are completely man made. The cicadas don’t know anything about years.

[@MephieStopheles]

@@MiamiPush2theLimit yes, because before man the earth did not orbit the sun, did not revolve, and had no seasons.

[@samuelstephens6904]

@@MiamiPush2theLimit Cicadas probably don’t “know” anything about anything, but that still doesn’t explain what triggers their emergence on the 13th or 17th year, especially when occasionally some individuals get it wrong and emerge early or late.

[@Dragrath1]

@@samuelstephens6904 Well counting neurons are a thing neurons in various animals which have a very specific job to count. There is even a disorder in humans where the counting neurons aren't working right called dyscalculia. All you need to do is have a counting neuron trigger at some seasonal signal perhaps the wake up of the tree in the spring and keep track of that somehow

[@aniruddhthakar1933]

Ah yes an American football field....the unit of measurement larger than a standard banana

[@Wakish0069]

America has more bald eagles per football field than any other country in the world

[@mfaizsyahmi]

americans measuring lengths: *bases them relative to tangible items* americans measuring temperature: "idk, 100 fEeLS HOT, 0 FeeLS COld lMAo"

[@johnkabiro7098]

There is risk in everything,so be prepared for ups and downs.

[@tonywells9608]

Diversification is relevant, and once you have confidence in your investment, you can adjust your profit and make bigger bets.

[@johnkabiro7098]

Just do the necessary research, study and analyze before making any investment.

[@genitarraw5463]

Many people are struggling from grass to grass, the concept of Bitcoin after it became a household name.

[@tonywells9608]

What's the secret, I bought Bitcoin at $11k but now it's$10,500. I'm losing.

[@johnkabiro7098]

@@tonywells9608 Really sad to know you Buy and hold.the best way to make money in Bitcoin is not storing, you trade in the forex market. As you're a beginner and don't know how to do this.i can recommend a certified broker for you.

[@thomas.02]

Ear splitting shrieks of millions of bugs looking for a mate Describes a street of nightclubs in a college town

[@Lorenzconnok]

This is fascinating! The 13 year lifespan and the 17 year lifespan cicadas will interbreed at their respective frequencies, then every 221 years they're guaranteed to overlap and guarantee genetic variance and a population boon. Kind of a cool life tactic. I wonder if there is a third, fourth etc. type with life cycles of other prime numbers🤔

[@Dragrath1]

There is apparently several species of periodical cicadas in my area they are past peak here but much of that peak was the largest species which all quickly emerged and did their thing. However then there was a smaller species of periodical cicadas that co time their emergence with the end of that spike in numbers they seem to be much more staggered with more emerging to fill the void of their dying brethren they also don't seem to have the same shade of red either. There is also a weird phenomenon where some percentage of the population will emerge early or late by either 1 or 4 years exactly. No one knows why this is but occasionally there is enough that emerge on these off years to set up a new viable brood. It is hypothesized this might have something to do with avoiding their fungal parasites.

[@rodefshalom]

I live in a college town near campus, so I’m used to the ear splitting shrieks of millions of bug looking for a mate.

[@TheSouperShow]

loving the long hair

[@MakeMeThinkAgain]

Thanks for that last video sequence of the cicada molting and leaving it's old shin behind. Those empty shells on tree trunks is what I remember about them from when I was a child in Kentucky.

[@Catssonova]

Michael's hair is anything but periodical, it is a constant and fabulous

[@flaviassimas]

I grew up in a very hot and dry state in Brazil. We used to think the loud buzz of cicadas was their way of requesting rain from the sky. It's probably because when they ceased singing, the rainy season would always arrive and we were all relieved :D

[@hi5dude2]

That's awesome tbh.

[@camerongrow6426]

"Magicicada" like Magic and cicada? I knew the scientific explanation is MAGIC!

[@amrys_argent]

I've tried with no luck to track down why they were given that name. My best guess is that the train of thought might have been: "Long life = wisdom = magi."

[@samuelstephens6904]

@@amrys_argent The name _Magicicada_ was given by Carl Linnaeus. _Magi_ is just Latin for “greater than” or “more.”

[@amrys_argent]

@@samuelstephens6904 Good to know, thanks!

[@dougalexander7204]

The content of this channel intrigued me. Thank you and stay awesome.

[@richardhall1667]

The last time i was this early, today’s cicadas were just nymphs.

[@jpwein88]

I live in the middle of the area of broods II and X so there’s a mass emergence every 8 years by me cause I’m by two broods

[@pkmn7777777]

I haven't watched this show in a while, glad to see Michael looking good!

[@cajintexas7751]

The songs of cicadas (or locusts, as we called them) is one of the familiar summer sounds of my childhood. We used to collect the empty shells of the nymphs, and catching a live cicada by hand was a feat of skill and patience.

[@karlbergen6826]

Here in Utah there is a cicada that comes our every year especially in areas that get some water from irrigation or a stream and not too many pesticides. This cicada is annual, (comes every summer) and is heared from July to October. It produces a high very steady sound which is actually quite pleasant.

[@rm6176]

They sound like the mother ship just hovering over Earth. That was my impression when I first heard them.

[@Arrslicker]

I don't know about anyone else, but SciShow is my all time clickbait. I see it, I click.

[@Feral_Fruit]

I can't believe Hank didn't get to do this episode and let out all of his cicada nerdiness 😢

[@prophetsam]

I grew up in the Tropics of South Florida, on the Eastern Seaboard, & there were Cicadas, & their Molted Skins, every year; in fact, there is Cicada Song in the Background of my Memories for almost the entire first 23yrs....

[@virglibrsaglove]

Yep. There are lots of different kinds. And not all of them stay underground so long. Their songs are a wonderful part of my childhood, too.

[@SuperFlamethrower]

Yes, "wild" peregrine falcons have about 1 chick a year and pairs that nest in cities have 4 chicks a year (because there's more food for them in cities).

[@sallybruska3245]

The first time I heard the cicadas was 35 years ago after I had moved to Maryland. There were so many you couldn't avoid walking on them or their shells. They were so loud your ears would ring afterwards. Amazing!

[@tedphillips2501]

Nymphs know when they have it good. I grew up where they loved Mango trees (the underground part) and would come up to mate. They would first climb up the tree trunk and shed their nymph exoskeletons, which you could collect off the tree bark, before filling the grove with their deafening sound. I wish I had thought at the time to dig down around the roots of the Mango trees to see if the nymphs could be found to see how they related to the tree. Maybe some of you can do this and do a video.

[@EayuProuxm]

Anybody else getting flashbacks to Higurashi: When They Cry?

[@hi5dude2]

Tbh, my flashbacks are Haruhi Suzumiya related.

[@felonyx5123]

@@hi5dude2 Kyon-kun, denwa~

[@virglibrsaglove]

I love cicadas! And videos about them. Also, I think this was the first time I heard Michael laugh. 👍

[@sumerbc7409]

In Oklahoma in the 80s as a kid, Cicadas come out every summer... my early childhood and teens can still hear their calls in the dog days of hot summer on school break ....

[@KaiserMattTygore927]

Haven't seen or heard any here lately.

[@ronjonchef2045]

Hope that Damascus steel fail was a one-off and this one you researched properly.

[@kdavis4910]

Scishow is wrong on occasion. I have noticed also.

[@kikojukic9156]

This channel has quality narrators.

[@Mai_lil]

Awesome video! Helps explain the new generation of cicadas that emerged recently

[@brentstorck3589]

Michael getting that ssj3 hair length. Just needs to die it all blonde and he’ll be battling it out with Majin Buu in no time.

[@nicoleonfeels]

Thank goodness we don’t have these on the west coast 😅

[@soaringvulture]

Why? I'd be thrilled to have a giant hatch every 17 years.

[@petergray7576]

We have cicadas here, only they're more solitary and don't have periodical cycles.

[@soaringvulture]

@@petergray7576 By "here", do you mean California? I haven't seen or heard any around San Francisco.

[@MiamiPush2theLimit]

Yes they are disgusting. I can’t wait to go home to Florida.

[@jake78441]

Bruh i love hearing Cicadas!

[@armageddonplace]

The prime number thing maybe explains avoiding predator cycles of 1, 2, 3, 4, 5, 6, 7 and 8 years. But why did they skip 11? 🤯

[@lizard3755]

I love Michael's hair like this, I hope he keeps it long

[@breeltoocool9842]

I’m on a trip to NJ and I heard them when I was at a foodcort

[@893263007]

Indiana is just passing the peak of it (which was apparently June 9). They are typically the loudest at about 3:30 pm.

[@judethaddeus9856]

I love seeing the evolution of your hair

[@vanessafrey3557]

Michael's hair is glorious

[@flordelphinta]

Perfect I needed this.

[@Katness07]

I don't remember cicadas in the parts of Montana where I grew up (Kalispell and Bozeman) Here in Phx, AZ they are annual, instead of 13 & 17 year cycles.

[@Chris-tz2um]

I'm glad this particular emergence was not similar to the locust emergence on Sera.

[@RosaLichtenstein01]

If you define a prime number as a number that can only be divided by itself and one (as you do in this video), then that will imply 1 is itself a prime number, which it isn't. A prime number is a natural number that has just two distinct natural number factors. That rules 1 out.

[@michaeltoney2277]

A wizard is never late, he arrives precisely when he means to.

[@raginirawat1915]

Thanks to scishow for offering us such a cute looking science professor 😄💕

[@Slow_o.O]

Southern AZ cicadas sound like every other North American cicada. If their noise was amplified and run through some kind of predator voice modulator. Also, they're around for the bulk of monsoon season. Not sure if individuals actually live that long though. Thanks to everything being crazier in the desert, they're around (in varying numbers) every year now.

[@OfficialSamuelC]

I find it fascinating that after say 15 years, they pretty much know the exact day, or at least week, that the cicadas will come out. They got it bang on right this year.

[@jakobraahauge7299]

Mikey! 🥰 Looking good, my Man! Looking good! 😙

[@johnlittle8975]

This sounds like an epicycle between the different species interaction

[@owlbme]

More videos about bugs please! 😁

[@tsya]

i enjoyed this ep! 4 mins went by so fast

[@melorawr1608]

Birds be like: "oh no prime numbers!" *Dies*

[@TheMightyN]

Apart from human interference and the depletion of probable food sources, most birds commonly live up to 10 to 20 years. So, it makes perfect sense why the population crashes once the Cicadas emerge from hibernation; therein, Cicadas have learned to calculate the age expectancy of their enemies. And you wonder where Ninjask got its name.

[@SpiralDown2077]

I love these little creatures Too cool

[@h7opolo]

awesome insights

[@SchnitzelDaemon]

Michael your hair is stunning

[@kdavis4910]

We have annual cicadas up north in Maine. They aren't out yet. They are summer bugs.

[@1MarkKeller]

So far so good for this year, very few cicadas in my area ... at the moment.

[@kilroywashere9343]

I live in NC. This is the first year in my memory where I can remember not hearing cicadas. It’s wild

[@samuelstephens6904]

Cicadas typically don’t emerge until late summer. Only periodical cicadas arrive in the spring.

[@umechanx00]

is it just me or michael's speech pattern is uncanningly similar to hank on this video?

[@shizenkv]

i live in north america but i dont think ive ever seen a cicada before and id like to thank god for that

[@AynneMorison]

In the Northern Region of Virginia - the 17 year cicadas sound like an alien mother ship coming to land. Too many of us in the local Sci-fi fan community agree on that one.

[@xoxo2008oxox]

For those not experiencing this, I'm in ground zero. They are LOUD. Their noise permeates through my house walls! They are everywhere. One landed on my shoulder and BRRRRRRRRRRRT. No, buddy, you are not mating on my shoulder so scram! I refuse to eat them as some suggest, but beware if you have shellfish allergy as these contain similar ingredients. And the 1yr brood has come up, so now they are competing in volume.

[@diamondjub2318]

it's part of the name, they gotta live up to the title

[@567secret]

Due to the breeding cycles being coprimal, they will inevitably go through spacings in their cycles of 0 to 13 years, but what occurs when one of the cicada cycles occurs 1 or 2 years after the other and the bird populations are high in this period?

[@SaltpeterTaffy]

"Their cycles tend to be one to ten years long." A one-year cycle should have no trouble syncing up with any cycle lasting a prime number of years. All prime numbers can divide by one.

[@paradoxiangd8525]

Micheal's hair reminds of rockstars from the 80s.

[@rainbow_vader]

Predators: I fear no man. But that thing, **Points at prime number** _it scares me_

[@KitsukiiPlays]

Magicicada is a pretty dope name

[@tylercooper1551]

All I know is the 17 year cicada makes for some really good fishing

[@warrenlemay8134]

I was outside in Cincinnati today working on taking down tree branches, and had cicadas landing on me thinking I was a tree, before they started chirping, and I had to brush them off. However, I also noticed something else - there were two different noises being produced by the insects, one of which is a "chhhhhhh" sort of sound I hear where I live in Northern Kentucky, but there was also a more distant sound that was more like "aaaaaaaaaaaoooooooo" and I am not sure why this is. May be a good video or study topic - why or how do periodical cicadas that emerge at the same time sometimes sound very different?

[@samuelstephens6904]

Cicada broods are actually composed of several different species with different matting calls. The buzzy “chhhhh” sound is probably the smaller _M. cassini_ while the “aaaaaoooo” sound is the larger _M. septendecim._ There’s also _M. septendecula_ which sound like a series of dry clicks and isn’t quite a noisy as the other two.

[@yanikore]

When I grow up I want to be as fab as Michael's hair

[@JCUDOS]

"Right before they sync up, every 221 years, is the perfect time to buy sesame seed stocks." - Peter Gregory

[@TK199999]

Its also not coincidence that the Sun is on a prime number cycle too, 11 years. So there could also be a correlation between the Solar cycles and emergence cycles.

[@taymccullough8775]

Here in Maryland the Cicadas are still crazy in population here and extremely loud

[@InternetLaser]

Crazy how cicadas only make the news when it's the new York brood even when brood 13 is much more numerous.

[@Insect_Expert1489]

Fun fact:” Did you that Tree Hoppers, Leaf Hoppers and Frog Hoppers are close cousins of Cicadas!!!”

[@trapfethen]

I propose marking your age by virtue of the number of periodical cicada emergence events you have witnessed. By a rough calculation, including both the 13 and 17 yr cycles, you get about 13 events before you die.

[@FB13]

Cicadas yasss

[@mikeissweet]

Wow. Haven't watched Scishow in a year or two. Looking different

[@vinjy2907]

This is literally the theme of Nausicaä of the Valley of the Wind

[@Wakish0069]

He looks so much better like this than he did like 10ish years ago lol, those gauges were too much

[@georgigeorgiev4871]

I believe that might be a survival mechanism. If you vanish for years on end, no animal can afford to specialize in hunting you.

[@sprucesoultree3833]

Currently experiencing the cicada invasion

[@Godlessfuture]

I'm from Indiana. Am I the only one that thinks the cicadas shrieks collectively sound like an UFO sound effect from a 90s video game?

[@marshall-brown]

They're loud AF and everywhere here in Indiana

[@ConstantChaos1]

I used to live near the cicadas, and this year I heard none since I'm not in the right region anymore