Motion helps you see things you might miss otherwise.
Click and hold to stop a shape's movement across the colored
background.
What do you see when you stop the shape inside the colored
background? What if it's only partially inside?
If a bird comes upon a grasshopper in a bush, the grasshopper
may freeze in its tracks. Why? Because the grasshopper has evolved
to protect itself by blending in with its surroundings, like
the camouflaged object in this simulation. And one way to blend
in is to
stop moving
—because motion reveals the
edges that separate a creature from the background.
Of course, predators can play that game too. For example, watch
a cat sneak up on a bird. If the bird begins to take notice,
the cat freezes in place. In the dangerous world of predator
and prey, motion is a dead giveaway—which is why motion
detection is such an important characteristic of most animals’
visual systems.
