Imagine them all ... crying

Would be great to know if all hell breaks loose every time
the dad walks out of the room or stops cootchy-cootchy!

I found this clip after participating in a survey on computer generated
laughter vs. human laughter. It was surprisingly difficult to decide on
some of the seven clips played, which one was which. The site also presents
short videos on the science of laughter - did you know, for example, that
rats giggle when they're tickled, and seem to enjoy the activity?

You can participate online here, it's a short and simple test, run by Acoustic Engineering
at Salford University, UK, supported by the New Scientist magazine.