The Evolution of the Heart (A Love Story)

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In order to understand where hearts came from, we have to go back to the earliest common ancestor of everything that has a heart. It took hundreds of millions of years, and countless different iterations of the same basic structure to lead to the heart that you have today.
Thanks as always to Nobu Tamura for allowing us to use his wonderful paleoart: spinops.blogspot.com/
Thanks to Ceri Thomas for the Ichthyostega reconstruction. Check out more of Ceri's paleoart at / alphynix and nixillustration.com
Produced for PBS Digital Studios.
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Katie Fichtner, Anthony Callaghan, Larry Wilson, Merri Snaidman, Renzo Caimi Ordenes, John Vanek, Neil H. Gray, Marilyn Wolmart, Esmeralda Rupp-Spangle, Gregory Donovan, Ehit Dinesh Agarwal, سلطان الخليفي, Gabriel Cortez, Marcus Lejon, Robert Arévalo, Robert Hill, Kelby Reid, Todd Dittman, Betsy Radley, PS, Colin Sylvester, Philip Slingerland, Jose Garcia, Eric Vonk, Tony Wamsley, Henrik Peteri, Jonathan Wright, Jon Monteiro, James Bording, Brad Nicholls, Miles Chaston, Michael McClellan, Jeff Graham, Maria Humphrey, Nathan Paskett, Connor Jensen, Daisuke Goto, Hubert Rady, Yuntao Zhou, Gregory Kintz, Tyson Cleary, Chandler Bass, Maly Lor, Joao Ascensao, Tsee Lee, Sarah Fritts, Ron Harvey Jr, Jacob Gerke, Alex Yan
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References:
www.ncbi.nlm.nih.gov/pmc/arti...
link.springer.com/article/10....
www.ncbi.nlm.nih.gov/pmc/arti...
onlinelibrary.wiley.com/doi/a...
www.ncbi.nlm.nih.gov/pmc/arti...
www.nature.com/articles/ncomm...
www.nhm.ac.uk/discover/news/20...
www.sci-news.com/paleontology/...
journals.plos.org/plosone/art...
www.ncbi.nlm.nih.gov/pubmed/7...
www.ncbi.nlm.nih.gov/pubmed/1...
genent.cals.ncsu.edu/bug-byte...
onlinelibrary.wiley.com/doi/f...
www.fossilmuseum.net/Fossil_Si...
www.tulane.edu/~bfleury/divers...
academic.oup.com/mollus/artic...
circsystems.weebly.com/mollus...
www.britannica.com/animal/mol...
onlinelibrary.wiley.com/doi/f...
www.thoughtco.com/evolution-o...
www.sciencedirect.com/science...
www.ncbi.nlm.nih.gov/pmc/arti...
www.ncbi.nlm.nih.gov/pubmed/2...

[@akhragee]

"It's also the only part of us that we say we can give to someone else" Great, now our kidneys are in the corner crying again.

[@JeffreyBoles]

Sensitive bunch aren't they?

[@m74568]

That or just ungrateful

[@OlOleander]

And the liver's gone out drinking again.

[@jezpin3638]

let me give you a hand. I would like to Express my feelings by giving you the middle finger. Or if people are happy with each other they give the D

[@drswag0076]

i think both the liver and brain can relate with said kidneys oh well

[@mikereslie3389]

I’d be very interested in seeing the evolution of the eye.

[@shawnwales696]

Click on that magnifying glass icon and search "evolution of eye" and you will get several documentaries on the subject.

[@duhduhvesta]

Mike Reslie this! I’d love to know but also the compound eye.

[@danilooliveira6580]

look for Richard Dawkins demonstration about the evolution of the eye, its amazing.

[@MasterJedi86]

Yes! Me to!

[@Infernoraptor]

Same I heard once that it evolved convergently more than 10 times?

[@arijitpalit2756]

Seriously, only the science channels can give me internal peace ☺

[@asz1029]

PBS Eons: Woooow, cool!! PBS Spacetime: I don't understand 70% of this, but cool. Kurzgesagt: Let's go and cry in the corner while thinking about our insignificance! Because Science: Do you really have to ruin the fun? Facts in Motion: The topic is interesting, but the sound makes me sleep. Also, are those Kurzgesagt animations?

[@arnbrandy]

You're probably discovered it by now, but when we talk about science + internal peace, Journey to the Microcosmos is amazing.

[@aryyancarman705]

Also Bob Ross

[@shivamshandilya573]

Vsauce : m gonna do what's called a pro gamer move(give u existential and identity crisis)

[@boktorinator693]

Same, but didn't expect Kiryu of all people to be watching PBS eons

[@SalianSaxon]

I would appreciate a video about "the evolution of seed plants" or "the recovery of vegetation after the permian mass extinction"

[@manassikdar1]

This

[@InnateDreams]

Bold of you to assume I have a heart beating in my chest.

[@quasar7683]

How are you alive?

[@JoaoPedro-qp9cw]

@@quasar7683 bold of you to assume he is alive

[@bigfootbuthesmokesweed6766]

@@JoaoPedro-qp9cw bold of you to assume they're a he

[@lordgarion514]

Bold? This is KZbin, Google knows everything.

[@patrickmccurry1563]

I don't know if anyone has one at the moment. But artificial hearts that don't beat have been tested on living people. They circulate blood continuously.

[@MedlifeCrisis]

Can't believe I missed this till now. Absolutely excellent video.

[@therealveridicalyt497]

That coming from a cardiologist terrifies me

[@yogurtmale1862]

@@therealveridicalyt497 lmao

[@fang609]

It's fascinating to know how many descendents came from the first creature with blood vessels. And even though all us with a heart may look deferent but we are essentially related through our hearts.

[@aresgood1]

it's not fascinating at all. it is to be expected. having blood vessels (even in the most primitive form imaginable) is still a huge advantage. whatever developed it first, it was obvious it and it's descendants will rule the world

[@SuperMerlin100]

We're still animals. We're multicellular eukaryotes, with an internal digestive system, and go through a blastula stage. The only definitions that exclude us do so explicitly. They give a list of criteria and then add except humans. Since we undergo gastrulation, developing multiple germ layers and clearly defined tissue, be're also eumetazoans. Literally true animals.

[@TheLokoschade]

I just wanted to say that the "hearts" in mollusks and insects have nothing to do with our hearts. Our evolutionary line splits very early off, way before hearts (or similar structures) existed . I feel like they didn't clarify that in the video enough.

[@SuperMerlin100]

The first living things were prokayotes, and at some point our ancesters gained a nucleus. So prokaryotes aren't a clade, for the same reason fish aren't. Bacteria and archea probaly are clades, but which of the 3 domains are closest is unclear. There seems to have been a lot of horizontal gene transfer involved, so there might not really be a clear cut answer.

[@comradesusiwolf1599]

Thats weird nature

[@quintenwhyte6660]

Host: "And the first vertebrates to walk on four legs." Ichthyostega[breaking the 4th wall]: "What's crackin'?"

[@contramuffin5814]

Ichthyostega: it is wednesday, my dudes

[@spindash64]

ContraMuffin If amphibians go extinct someday due to human activity, someone will write about about that day and then call it, “the last Wednesday”

[@spycrab3723]

@@spindash64 But, what if it was a Monday? It would be called; "I Hate Mondays."

[@WickedWildlife]

Could you do a video on the Marsupial Lion Thylacolio? They apparently had the highest bite force of any known mammal, dropped onto its prey from the trees and lived along side human beings for thousands of years, the original “drop bear!”

[@ryandika7443]

Who would win marsupial lion vs smilodon populator?

[@bigpapao8889]

ryan dika Smilodon populator, they outcompeted thylacosmilus, a creature similar to thylacoleo

[@Cheesecakeman105]

@@bigpapao8889 actually, some studies found it died out well before Smilodon even showed up in South America. About 500k years earlier.

[@WickedWildlife]

ryan dika would be no competition at all I’m afraid thylacolio was similar to a leopard where as some smiladon species where larger then lions! Mind you leopards are not less cool just because lions are more powerful...

[@jeznashalie]

Seconded

[@eddypalogrande6090]

6:20 Who else paused and reflected on the incredible development every creature undergoes even in their early stages of life. Thank you, PBS Eons, for putting together great educational information!

[@stopscammingman]

A lot of heart was put into this!

[@hotelbellamuerte3669]

It gets me pumped up

[@spycrab3723]

@@hotelbellamuerte3669 It made my hearty day.

[@DFloyd84]

Though we may look different on the outside, inside we are all the same. Pink and squishy.

[@phonn6935]

not true

[@CloudsGirl7]

Well, this is so much better than obligatory candy or flowers. Be my Valentine, Eons... ❤🌹🍫

[@jaschabull2365]

This just makes me wonder if Eons ever made an episode about flowers... The development of anthophyta sounds like a very interesting topic.

[@CloudsGirl7]

@@jaschabull2365 Don't know offhand, but I think they did make a video on the first flowers. ...I believe they did one on the evolution of sex, too. Welp. We're all ready for Valentine's Day. 😏😆

[@jaschabull2365]

Nothing about candy though... Unless there was an Eons episode about the domestication of sugar canes and beets. Now, that might be cool.

[@Patrick_The_Pure]

But who will your Eons Valentine be, is it Steve?

[@robertcowley-yamamoto4880]

Thank you for using the Greek plural suffix for octopus. Not many people know it, and more should because it's awesome

[@7seatea7]

Latin rather than Greek, but yes, it is much better than octopi.

[@robertcowley-yamamoto4880]

@@7seatea7 Nope Greek. Octopus is originally Greek in origin, hence the -odes plural suffix. The Latin plural suffix for words ending in -us is -i. And grammatically, both are technically correct in English

[@gertgregoor9466]

-i would only be the plural if octopus used the second declension, octopus uses the suffixes from the third declension. Hence both in Greek and Latin the correct plural would be oktopodes/octopodes. Octopi is however considered correct in English. Also octopus is a latin word, which indeed is derived from Greek, but in Greek it is oktopous.

[@sunworship5080]

@@gertgregoor9466 Yes both are correct now lets move on to the proper way to prepare baklava

[@tjmethven2074]

Octopuses

[@DrSepiro]

I think you missed an important part, about Birds circulatory system. Aside from the fact that it's amazing, it's also the most advanced of all circulatory systems, and for good reason (flying is HARD)

[@MrBlack0950]

Perfect Valentine's day video

[@jancukasu]

8:57 Thank you. The next time I give my heart away to someone, I'll make sure that she knows that my give is worth more than half billion years in the making.

[@MrIanJHoy]

I'm a musician, so is there any information on the evolution of hearing and communicating through sound?

[@lazycouch1]

I absolutely love this host. He presents well, is so friendly, brilliantly smart man. Even as a straight male I find him charming. I like science

[@ddsnutz2917]

Prehistoric love, the best kind of love

[@proudspark3853]

I remember being in class learning about the heart. Then here I am now. Clicking on this and enjoying it, not sleeping.

[@cadenrolland5250]

School is 18th century, this is 21st century. Welcome to the future

[@miguelpadeiro762]

@@cadenrolland5250 No.

[@Andy-xd5dj]

@@miguelpadeiro762 what is not correct about that statement besides present not being future?

[@miguelpadeiro762]

@@Andy-xd5dj What isn't correct is that he thinks he can be a heart surgeon/paleontologist by watching a youtube video about hearts aka school is useless and youtube videos are wayyyy better amirite

[@Andy-xd5dj]

@@miguelpadeiro762 probably referred to primary or high school lessons being boring and inefficient in terms of teaching, not university level I definitely took it in a way that studying can be done In a better way than how the current educational system is

[@kathrynedmunds9321]

Couple decade's ago, i searched the Lake Erie beaches. I like glass, pretty stones, tons of fossils. The day i picked the petrified palm size iron red heavyweight rock out of the sands along Lake Erie, i was stunned. I hollered to the universe that i had found a heart of early humans. I can see the flattened chambers, front and back. Odd find? on the beach.

[@evanmcloughlin5010]

I’d love to see an episode on the evolution of the brain. Maybe even the nervous system in general if that isn’t too much to ask.

[@mattwarmka1703]

What an apt Valentine's day video.

[@aureavita8653]

You caused the heart didn't you?

[@holysword876]

Our hearts are also fascinatingly complex. There is a reason why most congenital(fetus related) diseases are linked with the heart as the process that leads up to the formation of the heart is extremely elaborate and fascinating.

[@reflect7559]

I would love to see how hearing evolved. Thanks for another great episode!

[@shanmukhag2349]

I second.

[@Romanticoutlaw]

a tale as old as deep time

[@KAYEscl0sed]

"Like every other part of you, your heart is as complex as the story behind it. So the next time you give your heart away to someone, be sure that they know that your give is more than a half billion years in the making." Wow thanks

[@Summer-xe6in]

I truly appreciate this upload. Great timing and delicious information, PBS Eons! I really enjoyed coming home after work and watching this while eating dinner. Truly a pleasure to learn and understand the complex and ultimately fascinating story of our planets organisms and their existence and story throughout this journey we call, Life. I think this is even better that we don't know everything, makes learning, understanding, and wonder even more fulfilling and satisfying, for me, personally. :)

[@jamessmith65536]

Yummy. LOL.

[@Tomas-qk5fy]

That is beautiful, we have broken hearts and they mended themselves, Happy Valentine's Day to you

[@bee_whisper]

could you do a video on eyes . a spider has been discovered from the cretaceous which has a tapetum( reflective membrane)

[@fabiozwei]

I love both biology and history. This channel makes concise and entertaining content. Keep it up!

[@PartyDude_19]

I love both a lot as well

[@stephenz7238]

Wow. I’m in grade eleven biology right now and so much of this video links back to course material. 👏🏻👏🏻👏🏻

[@bleuemoone8710]

That's great! I'm currently in 2nd yr uni studying biology, and I've found the same to be true.

[@jaschabull2365]

Where's my college 101 squad at?

[@lilitheden748]

I’ve already learned about this a long time ago in school but every single time I see evolution in action I’m still awestruck. It never gets boring, the story of how everything came to be.

[@nate7790]

It's not the first video on PBS Eons where I notice this but I must say I find it really good that he talks of a "healthy debate" among researchers. He acknowledges that there are currently different opinions on the matter without any drama. Disagreeing about something and debating about it can lead to better understanding. It allows people to think in more than one way about the evidence we have and THIS to me is the heart (pun fully intended) of the scientific process. It's a good thing.

[@username-rs4vf]

Could you do a video on the evolution of multicellular life? Like how certain cells became specialized? Another cool episode would be chemical evolution to self replicating cells. I love it and this channel so this would be a dream.

[@carriertaiyo2694]

I love you guys at PBS Eons... with all my dorsal blood vessel! :D

[@gulchhh]

"Hey." "Hey." "Would you go out with -" "My heart was in million years of making." "O... kay...?"

[@Sofie424]

So has mine! We must be meant for each other.

[@GradyIsEpic]

This was an interesting one I've been waiting for! Thank you and I think the evolution of "sleep" would be really enlightening. Keep em coming!

[@MrJohnpilchard]

I fondly remember learning this as an undergrad majoring in developmental and evolutionary biology, yet the specific knowledge is now tucked away too securely in the the deep recesses of my ageing mind. Thank you to the team at PBS Eons for shining a light and providing a key to enable me to re-access these wonderful, inspiring stories!

[@genevievedisemelo5584]

literal body horror to realise that this can happen to memories does it not scare you to lose parts of yourself?

[@spacedolphincorp318]

Went to the google science journal. I didnt know Google was so much more awesome than id ever expect. THATS THE REASON WE ALL NEED GOOGLE FI. Thanks PBS-eons your videos bring my childhood dreams into reality

[@ViraL_FootprinT.ex.e]

6:16 Seeing the way the heart forms in embryos kind of blew my mind just now.

[@TheMango1198]

These are my favourite videos on this website, keep them up! I just spent the last year looking at embryonic development of the heart so it was really cool do get to look at the evolutionary implication of the topic!

[@cadenrolland5250]

From my heart to your PBS Eons

[@rhyswatson366]

I'd love to see a video on the evolution and early appearance of mycorrhizae! Soil fungi and plant symbioses are a very interesting topic (I think so, anyway), and these relationships were likely fundamental to early colonization of land.

[@Leftatalbuquerque]

There's no such a thing as a broken heart, It can't be shattered, can't be torn apart, It won't start bleeding when love seems gone, It just keeps beating on and on and on and on...

[@drewfisher1619]

Best valentine-themed video

[@gamaliel5584]

and some people still have the nerve to say we fell from the sky because of eating some fruit. we have a lot more in common with other animals than we do with angels, or whatever supposed to live up there. theyre not even real. i dont want to bring this up out of nowhere but seeing how often i have to deal with religious people and then watch a video like this afterwards, it gets under my skin. they need to learn a thing or two from this, or science in general. we've evolved through time and its apparent.

[@ryanvaughn5095]

I can see you guys put alot of heart into making this video.

[@lucainvernizzi9715]

Super small detail from a nitpick: the dna model at 5.50 is flipped :D Also, I'm new here and the channel is great. Adding the scientific references in the description is especially amazing!

[@josephhargrove4319]

Another informative video. Thanks. richard hargrove - A pun at maturity is fully groan.

[@veggieboyultimate]

a perfect video for a certain holiday! Do you think you can do evolution of the brain?

[@wonderfulfable]

This video goes well with the Evolution of Blood.

[@AlexAzureOtaku]

Heart video from my favourite youtube channel hosted by my eon crush! Happy valentine's to you too!

[@Totaku20]

This was incredibly fascinating! Thank you for the lesson. Is it possible to see a video on the evolution of brains? Or how different digestive systems evolved? I love your videos by the way! I can't stop binging them!

[@joelalvares8351]

Simply Amazing..... thanks for a lovely episode.....

[@mireyab813]

Omg! The history of all organs!!!! I love it!!!

[@CintreuseGrande]

I only realized this was inspired by Valentine's Day after it ended. Lol

[@Lucas-ix5td]

Make a video like that about every organ

[@tylermerlin8320]

A wealth of information explained extremely well. Thanks.

[@Mumble8988]

Wow, this video has a lot of heart in it

[@DerSaa]

Thank you so much.

[@virium4031]

Please, do a series on the immune system. Love you guys!

[@kingJr1229]

Was waiting for you guys to upload

[@mmcguire6286]

picture me jumping out of my chair and screaming with joy when he said "octopodes"!! !

[@baraskparas9559]

Great presentation. Thanks.

[@frost273]

Really cool presentation, complex and understandable at the same time. Nice touch of movement to the stationary images, makes me to be more attentive to the details.

[@CCumva]

What an awesome investigation! Brilliant!

[@falnica]

Birds have 4 chambered hearts as mammals do, but apparently they evolved independently. You should make an episode about that

[@spindash64]

Fernando Franco Félix Yeah, I was kinda hoping they’d talk about that. Crocodiles also have a system in their heart that lets them bypass the lungs while underwater, iirc.

[@Zharque]

I could feel my heart pumping throughout the entire video....

[@squidlord9110]

9:02 this made me chuckle Oh my dear I will love you forever, but first I must express my love by giving you a uni styled lecture on how the heart in our bodies evolved to be this way. Man my humor sux

[@BJETNT]

I always loved these videos!! One of the best

[@toddmitchellchristensen1848]

I'd really like some more anatomy evolution videos. Why do we have lips? Why do some animals have beaks? When did muscles first appear? Why don't we have claws?

[@tadeuantoniopassarelli1327]

AMAZING, thank you

[@wienzard36]

I appreciate the timing great video as usual 💙

[@bbear1928]

I heart you. Happy Valentines!

[@LeeSwab]

Ugh I love being on notif squad... Where would I be in life without Eons lmao

[@grimhavenz]

Lol I don’t have notifications but I still got here early

[@refink33]

this channel is amazing

[@monsoon_magic2874]

Great video. With a superb ending.

[@arturosolis8567]

Love this show! Great job guys:)

[@alxxxx70]

What a lovely story to tell Valentine's Day, well-done guys

[@robertjones9566]

Great job guys, amazing video

[@barkatullah1620]

What a heart felt story.

[@varunnikam]

This is the highest level of poetry by biology.

[@arkanin5634]

I have a small general question, when and how did the specialization of cells took place?

[@orthochronicity6428]

"octopodes" Can I give you a second like?

[@matthewlopez-duke6073]

Can you do a video on the Megafauna of South America? It’s a very interesting subject because of how everything evolved isolated and that made them very unique.

[@ancientsnox5093]

Best video for the occasion and the host is one of my favorites :)

[@olivergs9840]

I do like that you use the term ''Octopodes''

[@joeycook6526]

True story: I googled "the evolution of vertebrate hearts," a few weeks ago and couldn't find enough on it to satisfy my curiosity. Thanks for this video. Also, this marks the first time the internet has predicted what I want to watch or buy when I didn't get pissed off as a direct result and start talking about how I need to get a VPN.

[@cynopterusbrachyotis9919]

Mañana es San Valentín, y sí, una historia de amor.

[@richardjones8353]

Love this channel! I bet an episode on "ontogeny capitulates phylogeny" would couple nicely with this one

[@Argentarius11]

Wow!!! Fascinating!!!!

[@WHYNKO]

It is interesting to know that the same concepts (features) appears separately, multiple times... It's like life knows what's best for life to thrive.. and there is more than one way to do it.... I would really like you to make a video of an overview of the evolutionary path.. the journey life took to get here... Like the different features that came and went and a few were useful so it stayed... It would actually turn out to be a story of life's features their birth, evolution, and extinction...

[@stopscammingman]

This is very informative. I wonder what hypotheses there are about the evolution of pre heart tubes and what molecular clock data there is.

[@dustyprater7884]

Octopods. I love it. ❤

[@RainAngel111]

What a great topic to tackle on Valentine's day

[@NUSORCA]

Fuxianhuia is the one who truly deserves our valentine chocolate

[@bobjohnbowles]

I just noticed the date this was uploaded - day before Valentine's!

[@mackabokh2252]

Guys you are the best .