Why do we laugh?
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Why do we cry? The three types of tears
Whether we cry during a sad movie, while chopping onions, or completely involuntarily, our eyes are constantly producing tears. Alex Gendler tracks a particularly watery day in the life of Iris (the iris) as she cycles through basal, reflex and emotional tears.
Why is yawning contagious?
*Yaaawwwwwn* Did just reading the word make you feel like yawning yourself? Known as contagious yawning, the reasons behind this phenomenon have been attributed to both the physiological and psychological. It's been observed in children as young as four and even in dogs! Claudia Aguirre visits the many intriguing theories that might explain contagious yawning.
Why do we hiccup?
The longest recorded case of hiccups lasted for 68 years … and was caused by a falling hog. While that level of severity is extremely uncommon, most of us are no stranger to an occasional case of the hiccups. But what causes these ‘hics’ in the first place? John Cameron takes us into the diaphragm to find out.
Why do we itch?
The average person experiences dozens of individual itches each day. We’ve all experienced the annoyance of an inconvenient itch — but have you ever pondered why we itch in the first place? Is there actually an evolutionary purpose to the itch, or is it simply there to annoy us? Emma Bryce digs deep into the skin to find out.
Why do we sweat?There are a number of scenarios that can make us sweat–including exercise, eating spicy foods, and nervousness. But how does this substance suddenly materialize, and what exactly is its purpose? John Murnan explores the science behind sweat.
Why do we dream?
In the 3rd millennium BCE, Mesopotamian kings recorded and interpreted their dreams on wax tablets. In the years since, we haven't paused in our quest to understand why we dream. And while we still don’t have any definitive answers, we have some theories. Amy Adkins reveals the top seven reasons why we might dream.
Why do we love? A philosophical inquiry
Ah, romantic love; beautiful and intoxicating, heart-breaking and soul-crushing... often all at the same time! If romantic love has a purpose, neither science nor psychology has discovered it yet – but over the course of history, some of our most respected philosophers have put forward some intriguing theories. Skye C. Cleary outlines five of these philosophical perspectives on why we love.
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