Great question! Did you know that scientists at
UCSB are asking this very same question? They
would like to understand how these fish (and other
marine animals like them such as octopi and squid)
do this so that they can develop camouflage
technologies or other technologies such as solar
panels and materials that reflect or capture
light. By the way - have you seen a peacock
flounder in it's native habitat in the
Indo-Pacific oceans? I hope so - they are
The basic answer to your question is that
the fish has specialized cells in its skin that
contains various pigments (compounds that have
color) - these cells are somehow wired into the
vision of the fish. Whatever the fish "sees"
is transmitted to the cells and they adjust the
pigmentation to match the environment.
Scientists don't understand exactly how this
happens, but you can do an experiment to test the
connection between the eyes and the cells with the
pigment. Can you guess how?
Yep - scientists can cover up one eye with sand
(for example) and the fish has a really hard time
matching its color to the environment.
There are lots of ways for animals to
camouflage or to change color in response to
stimuli (especially for mating) and we are just
now starting to understand the molecules and the
biophysics of how that works. Scientists and
engineers are really curious about it because it
might give us new ideas about how to make better
or new devices - this is called "Bio-Inspired
Materials." Scientists are also just plain
fascinated by how these beautiful creatures change
color - just one more question about the amazing
world that we live in!