So, There's This Thing With Screaming

 We scream for a variety of reasons. A scream to get help when attacked is different from the screaming on a roller coaster.

Scientists studying screams discovered something interesting: We actually respond more quickly to "positive" screams than to "negative" ones.

That is to say, we react faster to somebody screaming in joy than we do to somebody screaming in pain. Which seems counterintuitive, because an "alert" scream would tell us there's a predator or a danger.

But it led me to an interesting thought.

Gibbons.

Gibbons are a type of small ape. They're highly arboreal, highly social, and they sing. One species, the siamang, even has an inflating throat sac so they can sing even more loudly.

They sing duets with their mates, they sing to mark their territory. It's a beautiful sound, but it's also loud. Trust me. There's a zoo in England with a major gibbon breeding program (Twycross in Leicestershire) and if you stick around to closing time they will serenade you.

Loudly.

And it's possible that the singing serves a similar purpose to, oh, wolves howling. Which humans find it very tempting to join in with.

It's kind of tempting to join the gibbons too.

Is joyous screaming something our hominid ancestors engaged in for the same reason? Do singing and screaming in joy share roots?

Do our brains tune in to joyful screams because at one point that was how we communicated over a distance in the forest?

It's...a thought.