Jan responds:
I have seen similar behavior in least and brindled madtoms and your
interpretation sounds good to me. Its difficult to know how a fish
perceives its environment. For example, conventional wisdom indicates that
paddlefish and sturgeons are not strongly sight-oriented but recent work
shows morphologically well-developed eyes with diverse and distinctive rod
and cone cells. Possibility exists for high-contrast vision, color vision
(perhaps), and sufficient image formation for visual feeding.
On a related topic - the latest issue of "Natural History" has an article on
fiddler crabs that is fascinating! It describes the new field of "visual
ecology" - the science of seeing and interpreting the world through the eyes
of the organism rather than the human observer. Fiddler crab researchers
have developed a crab-cam that simulates crab vision which is very different
than you might imagine (i.e., ground-level objects are seen as a band around
aerial objects, with closer objects appearing smaller than objects at a
distance). It would be neat (and I would guess simpler) to do the same for
fishes.
/-----------------------------------------------------------------------------
/"Unless stated otherwise, comments made on this list do not necessarily
/ reflect the beliefs or goals of the North American Native Fishes
/ Association"
/ This is the discussion list of the North American Native Fishes Association
/ nanfa_at_aquaria.net. To subscribe, unsubscribe, or get help, send the word
/ subscribe, unsubscribe, or help in the body (not subject) of an email to
/ nanfa-request_at_aquaria.net. For a digest version, send the command to
/ nanfa-digest-request_at_aquaria.net instead.
/ For more information about NANFA, visit our web page, http://www.nanfa.org