Biological

My notochord shall grow into
   a chain of vertebrae;
As fins my metapleural folds
  shall agitate the sea;
This tiny dorsal nervous tube
  shall form a mighty brain
And the vertebrates shall
  dominate the animal domain.
 
                - Phillip Pope, Zoologist

Ambystoma's a giant newt who
  rears in swampy waters,
As other newts are wont to do,
  a lot of fishy daughters:
These axolotls, having gills,
  pursue a life aquatic,
But, when they should
  transform to newts, are
  naughty and erratic.
They change upon compulsion,
  if the water grows too foul,
For then they have to use their
  lungs, and go ashore to prowl;
But when a lake's attractive,
  nicely aired, and full of food,
They cling to youth perpetual,
  and rear a tadpole brood.

                    - Walter Garstang, Zoologist

About the Guitar

The Rain Guitar  by James Dickey

La Guitarra  de Federico García Lorca