When we
see something new, we stare at it. But given a small magnifying glass, which
eye do you use. I tend use my right eye, which means the left side of my brain
is given the job of processing the image. The left hemisphere is where the
analytical approach is dominant and where the job of putting things into
categories by evaluating differences is done. The right side being more
freewheeling and creative, where we look for patterns and the like.
The
pressing question for today is: “do striped dolphins have a right or left eye
bias?” Humpback whales feeding at the bottom of the sea favor their right eye
for the job. Does that mean that they are being carefully analytical about what
they gulp down? Whales and dolphins favor their left eye when getting friendly
with their kin, which seems to fit in with a freewheeling, creative thinking.
However,
back to our striped friends. Siniscalchi et
al from the U of Bari “Aldo Moro” have presented their study of Stenella coeruleoalba in the wild in
this week's PLoSONE (1). The investigators dangled objects in front of
cavorting dolphins and recorded which eye they used to check the objects
out. They tried a striped soft ball, a
cuddly large-mouse toy and a life size plastic blue fish.
The
obliging dolphins got down and dirty with the plastic fish giving it the eye with
their left. Dolphins in the wild rarely come across striped balls or large
brightly colored cuddly mice and these toys were scrutinized with the other eye
that is, the right one.
All this
makes perfect sense to us mammals with the right side checking out what the
object looks like when compared to similar things and the left being used to
process novel things such as dangling cuddly mice in the middle of the ocean.
But this doesn’t seem to be the same with fish and birds who have the opposite
brain-side activities. Of course, we mammals don’t have feathers or scales
either. We went our own way a long time ago.
