Why does every mammal get 1 billion heartbeats in their life?

The hidden math that governs life. Sponsored by Brilliant - Try Brilliant for free, plus get 20% off an annual Premium subscription at https://brilliant.org/veritasium

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0:00 How much LSD should you give an elephant?
3:09 Metabolic Rate In Animals
5:27 The Surface Law
8:04 What is Kleiber’s Law?
10:49 Why is ¼ everywhere in biology?
13:33 WBE Theory
19:53 Every animal has 1,000,000,000 heartbeats
23:11 Why Humans Live Longer
24:31 Is it better to live in a city or a small town?
30:12 Is there really a universal scaling exponent for life?

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Much of this video was inspired by Geoffrey West’s book: Scale. Check it out here - https://ve42.co/ScaleBook

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Special thanks to the experts who helped make this video possible:
Brian Enquist, whose work helped inspire this video, for sharing the story behind WBE theory and helping us make its key assumptions and derivation more accurate.


Van Savage, for the generous and detailed feedback that sharpened our explanation of WBE theory, self-similarity, and the current state of the field.


Steven Strogatz, for the insightful conversations, on-camera contribution, and careful reviews that helped us keep the mathematics clear and the story scientifically honest.


Peter Sheridan Dodds, for helping us understand the objections to WBE theory and the debate over three-quarter-power scaling.

And the many other experts who discussed this topic with us as we were developing the script, for their invaluable contributions: Luis Bettencourt, Jayanth Banavar, Aaron Clauset, Juan Rubalcaba, and Douglas Glazier.

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References: https://ve42.co/ScaleRefs

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Special thanks to our Patreon supporters:

Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Sweet_Nemo, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee


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Writers - Daniel Leonard, Casper Mebius & Derek Muller
Producer & Director - Daniel Leonard
Presenters & Narration - Derek Muller & Henry van Dyck
Editors - Trenton Oliver, Axel Oliver & Jonny Lennard
Assistant Editor - James Stuart
Animators - Alex Drakoulis, Andrew Neet, Domonkos Józsa, Emma Wright & Fabio Albertelli
Illustrators - Jakub Misiek & Raphael Aubry
Simulations - Callum Cuttle & Aakash Singh Bagga
Researchers - Aakash Singh Bagga, Callum Cuttle & Gabe Strong
Thumbnail Designers - Abdallah Rabah & Daniel Ellacott
Thumbnail Design Direction - Ben Powell
Production Team - Jess Bishop-Laggett, Glen Griffiths, Matthew Cavanagh, Luke Lewis, Anna Milkovic & Justin St-Laurent
Executive Producers - Casper Mebius & Derek Muller

Additional video/photos supplied by Getty Images, Pond5 and Storyblocks
Music from Epidemic Sound