--- title: Humans Sleep Less Than Closely Related Mammals description: Some mammals sleep for 17 hours a day, we don't canonical: https://time.com/4149935/humans-sleep-mammals/ author: Victor Luckerson article:opinion: false article:content_tier: free article:published_time: 2015-12-15T19:04:52.000Z article:modified_time: 2026-02-22T13:23:39.043Z article:section: Science og:title: Humans Sleep Less Than Closely-Related Mammals og:description: It’s because our sleep cycles are more efficient og:url: https://time.com/4149935/humans-sleep-mammals/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt63cf1de250aa1296/69887571e20a871ddfa8ea85/sleep.jpg?branch=production&width=1200&quality=75&auto=webp&crop=16:9 og:image:width: 4689 og:image:height: 2638 og:image:alt: sleep og:type: article twitter:card: summary_large_image twitter:title: Humans Sleep Less Than Closely-Related Mammals twitter:description: It’s because our sleep cycles are more efficient twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt63cf1de250aa1296/69887571e20a871ddfa8ea85/sleep.jpg?branch=production&width=1200&quality=75&auto=webp&crop=16:9 ---  # Humans Sleep Less Than Closely-Related Mammals > Sponsored content. 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It reaches 40,000 subscribers with a 34.2% open rate and a 2.1% click rate as of August 2026. #### Where can I follow the energy transition as a business story? Future Proof covers climate and energy as an economic and business story rather than only an environmental one. It publishes every Friday and is free at time.com/newsletters. #### Who writes Future Proof? Justin Worland, a senior correspondent at TIME and an award-winning climate journalist, writes Future Proof. #### Is Future Proof free? Yes. Future Proof is free at time.com/newsletters. by [Victor Luckerson](https://time.com/author/victor-luckerson/) ## Victor Luckerson Dec 15, 2015 7:04 PM UTC  Getty Images by [Victor Luckerson](https://time.com/author/victor-luckerson/) ## Victor Luckerson Dec 15, 2015 7:04 PM UTC Even if you’re managing to get eight hours of sleep every night, you’re still sleeping way less than gray mouse lemurs or African green monkeys. That’s according to a new study by Duke University researchers which found that humans tended to have much shorter and more efficient sleep cycles than other mammals. The average person gets just seven hours of sleep, while species like the gray mouse lemur sleep for as many as 17 hours per day. Part of the reason humans get by sleeping less is because we spend more time in deep sleep. Dream state rapid eye movement sleep comprises 25% of a person’s nightly slumber, while accounting for just 5% of the nightly sleep of mongoose lemurs and other mammals. Researchers also found that constant exposure to artificial light and computer screens wasn’t making people sleep less. People in hunter-gather societies who don’t use electricity were found to sleep slightly less than people who regularly use modern technology. \[[_Science Daily_](http://www.sciencedaily.com/releases/2015/12/151214130926.htm)\] ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4149935/humans-sleep-mammals/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4149935/humans-sleep-mammals/"},"headline":"Humans Sleep Less Than Closely-Related Mammals","datePublished":"2015-12-15T19:04:52.000Z","dateModified":"2026-02-22T13:23:39.043Z","description":"It’s because our sleep cycles are more efficient","url":"https://time.com/4149935/humans-sleep-mammals/","keywords":["animals","Sleep"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt63cf1de250aa1296/69887571e20a871ddfa8ea85/sleep.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Victor Luckerson","jobTitle":null,"url":"https://time.com/author/victor-luckerson/"}],"articleSection":"Science","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt63cf1de250aa1296/69887571e20a871ddfa8ea85/sleep.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"sleep","caption":"sleep","creditText":"Getty Images","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/science/","name":"Science"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/animals/","name":"animals"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/4149935/humans-sleep-mammals/","name":"Humans Sleep Less Than Closely-Related Mammals"}}]}] ```