Laughter

It began at a girls' school in what is now Tanzania and spread to nearby villages.

Chimpanzees, gorillas and orangutans produce panting sounds during tickling and play.

Researchers examine how and why humans laugh.

Laughter appears long before a child learns to speak.

Hearing others laugh can trigger laughter in the listener, even without a joke.

Toddlers can laugh up to 400 times daily, experiencing joy effortlessly and spontaneously. In contrast, adults average only 15-20 laughs per day, highlighting a potential decline in spontaneous playfulness and mirth as we age.

Studies show that laughter increases the production of antibodies and activates T-cells, strengthening the body's defenses against illness. It also reduces stress hormones that can suppress the immune system, promoting better health.

While inaudible to the human ear, rats emit high-frequency vocalizations (50-kHz chirps) when tickled or engaged in play. These sounds are associated with positive emotional states, similar to human laughter, indicating joy.

It triggers the release of endorphins, the body's natural feel-good chemicals, which can temporarily relieve pain and induce a sense of euphoria. This effect is often compared to a "runner's high" and can reduce discomfort.