Why Do Humans Cry But Animals Don't?

Why do humans cry emotional tears when no other animal seems to? 😢 Your dog can whimper, howl, and tremble when it's sad, but it won't cry the way you do at a sad movie. In this video we look at the science of tears: what animals actually do with them, what makes human tears different, and the leading theories for why we evolved to cry. ⏱️ CHAPTERS 0:00 The tear at the movies 0:30 It gets stranger: the 2011 sniff experiment 1:02 Animals DO make tears (turtles, crocodiles and more) 1:44 The 3 types of human tears 2:44 Do any animals cry from emotion? Elephants, chimps and mice 3:30 Dogs, oxytocin and the 2022 Japanese study 4:15 Theory 1: helpless babies and the cry for care 5:04 Theory 2: tears as an honest signal of vulnerability 6:13 Theory 3: the chemistry of tears 7:00 Does a good cry really make you feel better? 7:38 What your tears really are 🔬 WHAT YOU'LL LEARN Why sea turtles and seabirds "cry" without being sad Why crocodile tears are a mechanical side effect, not remorse The difference between basal, reflex, and emotional tears Why the elephant weeping stories are still just anecdotes How dogs' eyes get wetter when their owners come home Why babies scream from birth but only produce tears weeks later How a 2011 study found that sniffing women's tears lowered men's testosterone When crying helps you feel better, and when it doesn't 📚 STUDIES AND RESEARCHERS MENTIONED Weizmann Institute of Science (2011), tears and testosterone, published in Science Japanese research team (2022), dogs' tear volume and reunions with owners, published in Current Biology William Frey's research on the chemistry of emotional tears (still debated and not fully replicated) Ad Vingerhoets, on tears and infant helplessness Oren Hasson, on tears as an honest signal of vulnerability Lauren Bylsma, on when crying improves mood The science of tears is still young and many of these ideas are still being debated, so treat the theories as leading hypotheses, not settled facts. 💬 TELL ME IN THE COMMENTS: What's the last thing that made you cry? I read every one. 👍 If you enjoyed this, like the video and subscribe for more explainers on the strange science of everyday life. #crying #tears #animalbehavior #science #psychology #evolution #dogs #explainervideo