You can check out Google's Science Journal app at https://g.co/sciencejournal

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: http://spinops.blogspot.com/

Thanks to Ceri Thomas for the Ichthyostega reconstruction. Check out more of Ceri's paleoart at http://alphynix.tumblr.com and http://nixillustration.com

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Super special thanks to the following Patreon patrons for helping make Eons possible:

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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Want to follow Eons elsewhere on the internet?
Facebook - https://www.facebook.com/eonsshow
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References:
https://www.ncbi.nlm.nih.gov/p....mc/articles/PMC53784
https://link.springer.com/arti....cle/10.1007%2Fs00018
https://www.ncbi.nlm.nih.gov/p....mc/articles/PMC26142
https://onlinelibrary.wiley.co....m/doi/abs/10.1111/j.
https://www.ncbi.nlm.nih.gov/p....mc/articles/PMC30974
https://www.nature.com/articles/ncomms4560
http://www.nhm.ac.uk/discover/....news/2014/april/earl
http://www.sci-news.com/paleon....tology/science-fossi
https://journals.plos.org/plos....one/article?id=10.13
https://www.ncbi.nlm.nih.gov/pubmed/7915669
https://www.ncbi.nlm.nih.gov/pubmed/10355031
https://genent.cals.ncsu.edu/b....ug-bytes/circulatory
https://onlinelibrary.wiley.co....m/doi/full/10.1111/b
http://www.fossilmuseum.net/Fo....ssil_Sites/whitesea/
http://www.tulane.edu/~bfleury..../diversity/labguide/
https://academic.oup.com/mollu....s/article-abstract/4
https://circsystems.weebly.com/mollusca.html
https://www.britannica.com/ani....mal/mollusk/Evolutio
https://onlinelibrary.wiley.co....m/doi/full/10.1111/j
https://www.thoughtco.com/evol....ution-of-the-human-h
https://www.sciencedirect.com/....science/article/pii/
https://www.ncbi.nlm.nih.gov/p....mc/articles/PMC44596
https://www.ncbi.nlm.nih.gov/pubmed/28905992

Over the first season of PBS Eons, we’ve explored the history of Earth from the very origins of life right up to the Cenozoic Era that we’re in now. To celebrate our first anniversary together, we’d like to answer some of your most frequently asked questions.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Super special thanks to the following Patreon patrons for helping make Eons possible:
Aldo Espinosa Zúñiga, Betsy Radley, Svetlana Pylaeva, Colin Sylvester, Philip Slingerland, John Vanek, Jose Garcia, Noah offitzer, Eric Vonk, Tony Wamsley, Henrik Peteri, Jonathan Wright, Wilco Verweij, Jon Monteiro, James Bording, Brad Nicholls, Miles Chaston, Michael McClellan, Elysha Nygård, Jeff Graham, Maria Humphrey, Nathan Paskett, Connor Jensen, Ehit Dinesh Agarwal, Sapjes, Dave, Daisuke Goto, Zachary Winkler, Hubert Rady, Yuntao Zhou, Gregory Kintz, Tyson Cleary, Chandler Bass, Maly Lor, Joao Ascensao, Tsee Lee, Sarah Fritts, phil parker, Ruben Winter, Ron Harvey Jr, Joshua Mitchell, Johnny Li, Katie Fichtner, Budjarn Lambeth, Jacob Gerke, Katie M Vasilescu, Brandon Burke, Alex Yan, Jordon Sokoll

If you'd like to support the channel, head over to http://patreon.com/eons and pledge for some cool rewards!

Want to follow Eons elsewhere on the internet?
Facebook - https://www.facebook.com/eonsshow
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References:
https://www.nature.com/articles/nature24679
https://www.researchgate.net/publication/265553416_Semiaquatic_adaptations_in_a_giant_predatory_dinosaur?enrichId=rgreq-d298c20fbadcb0c1e9961c1c4f7d401f-XXX&enrichSource=Y292ZXJQYWdlOzI2NTU1MzQxNjtBUzoxNTgyODkzNTQ1Njc2ODBAMTQxNDc1MDUzMTMyNw%3D%3D&el=1_x_3&_esc=publicationCoverPdf
https://www.theatlantic.com/sc....ience/archive/2016/0
http://quaternary.stratigraphy.....org/workinggroups/a
http://www.igbp.net/download/1....8.316f18321323470177
https://www.sciencedirect.com/....science/article/pii/
http://www.pnas.org/content/pn....as/113/15/3908.full.

Check out our other journeys through geologic time here :
https://www.youtube.com/playli....st?list=PLi6K9w_UbfF

Viewers like you help make PBS (Thank you

Dedico a você Renata...eu te amo....sempre te amarei minha amiga....muaaaaaaaaaaaa....Rose.

A-Ha - Hunting High And Low - Tradução

Performing their first 2 albums accompanied by the Oslo Philharmonic Orchestra.
From a-ha's second album Scoundrel Days

Taking advantage of bees aggregating for mating season, birds have a banquet.
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Wild West
This wild frontier has been forged by the elements and built by monumental forces. Over millennia America's most iconic landscapes have been carved out; wind sculpted deserts, like Death Valley and the Grand Canyon; giant redwood forests fed by precious waters; and extreme coastlines - from the wave sculpted shores of the pacific to the warm sheltered sea of cortex. Nowhere in America is more extreme, more varied and more spectacular than the Wild West.

Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of astounding, entertaining, thought-provoking and educational natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this.

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Taken from Snow Wolf Family And Me. In such a harsh and wild environment it's wonderful to see the family strength and community of a wolf pack and how they interact with a human in there domain.

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Breath-taking images of a wolf chasing and capturing a caribou in the wild. Brilliant images from BBC natural history masterpiece, Planet Earth. Visit http://www.bbcearth.com for all the latest animal news and wildlife videos and watch more high quality videos on the new BBC Earth YouTube channel here: http://www.youtube.com/bbcearth

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Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of astounding, entertaining, thought-provoking and educational natural history content.

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These amazing Bottlenose Dolphins have adopted a unique way of hunting Fish. Taking advantage of the low tide, these super smart Mammals are able to beach themselves on mud banks, and attack in perfect synchrony.

Taken From The Hunt

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As the cubs grow up Giles Clark thinks it's time for Spot and Stripe to start socialising with the adult tigers. Taken from Tigers About The House. Subscribe: http://bit.ly/BBCEarthSub

Watch David Attenborough Dynasties series trailer here: https://www.youtube.com/watch?v=JWI1eCbksdE --~---

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Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of astounding, entertaining, thought-provoking and educational natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this.

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John Hurt narrates the facts behind the discovery of huge Argentinosaurus nesting site in modern day Patagonia. Subscribe to BBC Earth: http://bit.ly/ydxvrP

Narrated by John Hurt Planet Dinosaur tells the stories of the biggest, deadliest and weirdest creatures ever to walk the Earth, using the latest fossil evidence and immersive computer graphics.

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Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of astounding, entertaining, thought-provoking and educational natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this.

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Predator X is back, hunting in deep water where it's able to use it's full power, derived from it's massive size.

Narrated by John Hurt Planet Dinosaur tells the stories of the biggest, deadliest and weirdest creatures ever to walk the Earth, using the latest fossil evidence and immersive computer graphics.

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In this shocking footage from the BBC Wild Africa series, a crocodile tries to attack a herd of buffalo, without success. Subscribe: http://bit.ly/BBCEarthSub

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Welcome to BBC EARTH! Here you'll find 50 years worth of astounding and thought-provoking natural history content. Dramatic, rare, and exclusive, animal videos and nature don't get more exciting than this.

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Follow lions throughout the different stages of their lives and watch them grow from cute cubs to formidable hunters. What does it take for a lion to survive as an adult?
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Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of astounding, entertaining, thought-provoking and educational natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this.

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Canada’s green seas are home to some surprising creatures. From fascinating wolf eels to the largest known octopus in our oceans. Take a deep breath and join diver Tiare Boyes on an adventure into an underwater forest. Use your headset to watch this video in 3D Virtual Reality.
This dive experience was filmed in 3D 360 and utilises spatial sound. Turn up the volume and take a deep breath. Introduced by Patrick Aryee.
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Our Blue Planet VR is a BBC Studios Natural History Unit production.

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Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of entertaining and thought-provoking natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this.

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From the majestic snow leopard to the powerful polar bear, this compilation celebrates some of the most treasured and highly endangered species from the BBC Archive.
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#AnimalsNearingExtinction #AnimalCompilation #BBCEarth

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Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of entertaining and thought-provoking natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this.

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These chimps need to improve on their teamwork in order to procure food.
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Chimps Of The Lost Gorge
In Uganda, the team follows a special family of chimps that were trapped by encroaching villages 10 years ago, too afraid to walk the 8kms that separates them from their rich forest home. The chimps' number is down to 20 and their babies are all males. Already forced to inbreed, if they don't escape the family will self-destruct. Will they risk the dangers of the open-savannah in the search for freedom?

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An Elephant family is crossing a river, but the currents are too strong and the calves risk getting swept away.
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24/7 Wild:
Witness the most charismatic animals on earth as they experience life's ultimate challenges in the first few vulnerable weeks of life. 24/7 Wild journeys with them to understand their tough rites of passage to adulthood and survival.

Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of astounding, entertaining, thought-provoking and educational natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this.

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Animals must try to gain a position of power in their world, this young male chimpanzee wants to be accepted as part of the elite but it's a dangerous journey...Taken from Life Story.

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From their very first breath to their last, the tiger has captured the heart of BBC audiences worldwide - here are the best of our tiger moments.
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Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of entertaining and thought-provoking natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this.

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