Click to subscribe to Vsauce: http://bit.ly/POIaN7 Check out Veritasium's channel: http://bit.ly/YY7KDe LINKS and SOURCES below. Follow me on twitter! http://www.twitter.com/tweetsauce Music by Jake Chudnow http://www.soundcloud.com/jakechudnow null Veritasium video on single photons and frog eyes: https://www.youtube.com/watch?v=cztocbHiiqQ British Pathe Robert Wadlow video: https://www.youtube.com/watch?v=5McWw03Ryrs Earth Unplugged channel: null AsapScience Moon Illusion video: https://www.youtube.com/watch?v=49RztN4Bqu0 interactive DNA model: http://learn.genetics.utah.edu/content/begin/dna/builddna/ Igor Vovkovinsky: http://www.thetallestman.com/igorvovkovinskiy.htm Sultan Kösen: http://en.wikipedia.org/wiki/Sultan_K%C3%B6sen Robert Wadlow: http://en.wikipedia.org/wiki/Robert_Wadlow André the Giant: http://twentytwowords.com/2012/01/26/andre-the-giant-holding-a-can-of-beer/ http://en.wikipedia.org/wiki/Andr%C3%A9_the_Giant tallest woman: http://www.thetallestman.com/zengjinlian.htm human height: http://io9.com/5789332/in-search-of-the-worlds-tallest-human http://erinjenne.blogspot.co.uk/2011_02_01_archive.html http://webcache.googleusercontent.com/search?q=cache:lL-vNccMG8MJ:www.naturalheightgrowth.com/2012/09/20/what-is-the-tallest-theoretical-height-of-the-human-species/+&cd=3&hl=en&ct=clnk&gl=uk Genetic manipulation of height: http://www.theage.com.au/articles/2004/04/11/1081621836499.html Square-cube law: http://en.wikipedia.org/wiki/Square-cube_law Largest dinosaurs: http://www.walkingwithdinosaurs.com/news/editorial/biggest-dinosaurs-amphicoelias-bruhathkayosaurus/1/ Giraffatitan: https://en.wikipedia.org/wiki/Giraffatitan Bruhathkayosaurus: https://en.wikipedia.org/wiki/Bruhathkayosaurus http://smart-pustaka.blogspot.co.uk/2011/09/bruhathkayosaurus-matleyi.html Blue Whale: Mars and Earth comparrison: http://upload.wikimedia.org/wikipedia/commons/9/93/Mars_Earth_Comparison_2.jpg Mars-born people being taller: http://www.lifeslittlemysteries.com/1160-would-humans-born-on-mars-grow-taller-than-earthlings-.html biology of body size and shape: http://dinosaurtheory.com/scaling.html http://fathom.lib.uchicago.edu/2/21701757/ http://galileoandeinstein.physics.virginia.edu/lectures/scaling.html http://supersonicman.wordpress.com/2011/11/13/the-square-cube-law-all-animals-jump-the-same-height/ https://en.wikipedia.org/wiki/Allometry Guy Murche book: http://www.amazon.com/The-Seven-Mysteries-Life-Murchie/dp/0395957915 Sound calculator: http://www.sengpielaudio.com/calculator-distancelaw.htm How far away is the horizon? http://mintaka.sdsu.edu/GF/explain/atmos_refr/horizon.html http://en.wikipedia.org/wiki/File:How_far_away_is_the_horizon.png http://www.howitworksdaily.com/environment/what-is-the-maximum-distance-the-human-eye-can-see-if-unobstructed/ Angular size: http://en.wikipedia.org/wiki/Angular_diameter http://burro.astr.cwru.edu/Academics/Astr221/Light/parallax.html Anuglar size calculator: http://planetcalc.com/1897/ Smallest angular size naked eye can see: http://adsabs.harvard.edu/full/1994JBAA..104...86W Animal olfaction: http://en.wikipedia.org/wiki/Olfaction#Olfaction_in_plants_and_animals Human body radiation emission: http://en.wikipedia.org/wiki/Black-body_radiation#Human_body_emission Humans emitting light in visible spectrum: http://www.livescience.com/7799-strange-humans-glow-visible-light.html Final .gif: http://i.imgur.com/X8M5X.gif