http://news.sciencemag.org/sciencenow/2009/06/04-01.html
It's something all humans do, regardless of race, culture, language, or creed: laugh.
And, it turns out, some 10 million to 16 million years ago, the last common ancestor of humans and apes was laughing, too, most likely when tickled.
That's the conclusion of an analysis of the recorded laughs of young orangutans, chimpanzees, and human children....
Very true....thanks! Fred
ReplyDeleteYou're welcome, Fred...
ReplyDeleteReactions to tactile touch,
particularly to that related
to playing and social relations,
is essentially the same for
humans and apes as well.
Only differs with when and how it sounds:
we laugh only while exhaling,
but apes laughed while inhaling too.
Ours are more "voiced" sounds
that yield rich harmonics because
of the vibration of the larynx's
vocal folds at regular frequencies,
while theirs are more "noisy" sounds
like grunts from irregular
vocal folds vibrations.
When tickled, there arise
some involuntary movements
causing laughs...
One question though is,
could the laugh also be a psychological
reaction more than physiological?
Some humans particularly sensible
to tickling frequently start laughing
even before being really touched,
as a defense or conditioned reflex
against more possible physical contacts....