Great video about that by Kurzgesagt: https://www.youtube.com/watch?v=bgo7rm5Maqg&ab_channel=Kurzgesagt%E2%80%93InaNutshell https://www.youtube.com/watch?v=bgo7

Great video about that by Kurzgesagt: https://www.youtube.com/watch?v=bgo7rm5Maqg&ab_channel=Kurzgesagt%E2%80%93InaNutshell https://www.youtube.com/watch?v=bgo7rm5Maqg&ab_channel=Kurzg... They show how deep they had to go to find the original source of the claim that a single human's blood vessels, if lined up, would stretch 100,000km... and how that was quoted by so many that no one really know where the claim came from. And of course, it was wrong.