Why do we scream?

Image courtesy of CC0, Public Domain.




Joel Kontinen

"Screaming Is well-studied in animals, where it's thought the behaviour has evolved as a way to startle an attacking predator and provide a chance to escape, or, in social animals, to recruit help when in trouble.

Surprisingly, much less is known about how human screams function in communication, or how similar or different human screams are from those of other species."

Now, the article in Medical Xpress does not say that screaming evolved, but it look at people just as if they are animals and says it evolved from something, as laughter did.

Only humans are known to cry for emotional reasons.


Source:

Acoustical Society of America. 2019. Scientists suss out the secrets of human screams. Medical Xpress (15 May).

Laugh Like An Ape?

Don’t tickle me. New ape study examines similarities between laughter in humans and apes.




Joel Kontinen

Since the days of Charles Darwin, evolutionists have attempted to see human traits in animals and animal traits in humans. A new study published in the journal Current Biology observes this tradition of Darwinian storytelling faithfully.

A research team led by psychologist Marina Davila Ross of the University of Portsmouth, UK, tickled 21 young orangutans, gorillas, chimpanzees, bonobos, as well as one siamang and three human babies. They examined the resulting laughter, using 11 acoustic variables.

Davila Ross and her colleagues concluded that the laughter of the gorillas and the bonobos resembled human laughter most.

It might still be difficult to bridge the gap between apes and humans with laughter. Apes prefer to use four legs for walking and they usually breath in synchrony with their walking. Humans are able to breath independently of their walking and are not known to crawl on all fours.

The difference in how humans and apes laugh might remain a ticklish issue. After all, laughter is not the only thing that separates us.

Professor Stuart Burgess of the University of Bristol, UK, has pointed out that whereas apes have about 26 facial muscles, humans have approximately 50. Moreover, with all their muscles apes can produce four expressions, none of which are especially pretty. In contrast, humans can produce 10 000 expressions. Some of them can be quite beautiful.

It might thus be difficult to make monkeys out of humans with any amount of laughter. Or humans out of apes.

Moreover, one should probably only choose small apes for laughter experiments. A King Kong sized gorilla might bite the researcher’s little finger, in spite of its being Darwin year.

Sources:

Burgess, Stuart. 2006. The Design Argument. Lecture in the Creation Without Compromise conference in Swanwick, UK, 22 April 2006.

Laursen, Lucas. 2009. Human-ape links heard in laughter. Nature news 4 June.
http://www.nature.com/news/2009/090604/full/news.2009.541.html