> Vision has proven to be a very effective means of processing information about
> the environment and vision is the most important sensory modality for humans.
> It would be
> pretty surprising to me if it weren't important in most alien species (if they
> exist) as well.
Again, studies of cetaceans have show that their sonar 'vision' is as acute as
our optical vision. Not only that, because of the nature of sound, they can
'see' through many of the objects they bounce sounds off. This give them a
unique kind of 3-d hologaphic perception of the world around them.
Paul