The Body Cavity in the Bird (Cloaca)

Lyrics

[Intro]
The classroom is fifty-five degrees.
The smell of formaldehyde and old chalk.
Pale sun through the window at ten-thirty AM.

[Verse 1]
This is a sparrow. Passer domesticus.
Pinned to the tray with small steel pins.
Its ventral side is exposed to the morning light.
My textbook is open to page one-seventy.
'Elements of Zoology' by Tracy Storer, 1945.
He drew it just like this.

[Verse 2]
I take the magnifying glass, the one with the brass handle.
Lean in close, feel the cold edge of the desk on my arms.
You can hear the chairs scrape on the floorboards.
Aristotle noted it first, around 350 BCE.
John Ray confirmed it in his Ornithologiae Libri Tres, in 1676.
A singular structure.
A common passage.

[Chorus]
It is called the cloaca.
One opening for the reproductive and the excretory.
For the egg and for the waste.
The bird makes no distinction.
It is an instrument, as da Vinci wrote.
Working according to mathematical law.

[Verse 3]
There is no bladder to hold.
No separate passage for the urea.
Conrad Gessner wrote in 1555.
An efficiency for creatures of the air.
Lightness is everything.
The design is final.

[Bridge]
In the ostrich, it can evert.
Turn itself inside out for a moment.
Like a strange pink balloon inflating.
Then it is gone.
There is no record of what the first students thought.
Their names are missing from the record.
Their shock is unwritten.

[Chorus]
It is called the cloaca.
One opening for the reproductive and the excretory.
For the egg and for the waste.
The bird makes no distinction.
It is an instrument, as da Vinci wrote.
Working according to mathematical law.

[Outro]
I place the magnifying glass beside the tray.
The lesson is concluded.
The dust motes turn in the sunbeam.
The silence in the room is also a kind of law.