Dinstinguished professor Jackie Gibson, Cornell, based her research on a
decades-long study to ascertain at what age babies obtain depth perception.
She let babes of various ages crawl out across a surface that at a certain
point became see-through. If the babe looked down and continued forward, she
checked the box Does Not Have Depth Perception. If the babe stopped, looked
down, became upset or otherwise involved in the view below, she checked the
box Does Have Depth Perception. I mean, the whole thing was actually a lot
more complex and arcane than that, but them's the basics. I was a "visual
cliff baby," and so was my daughter (now 17) but by that time Jackie was
letting em crawl across water beds and all manner of other freaky surfaces.
My mom says I cried. My daughter had a hell of a good time jiggling the
water bed.
Progress,
HLH