They Come in Seven Sexes
An old wing of the university
housed the laboratory.
She passed through a narrow corridor
oozing the autumn moisture
of the morning rain.
She put on a white polyester coat,
adjusted her seat and then
placed the Tetrahymena
under the microscope.
“What are you doing? ”
asked suddenly a baritone voice.
Ruth looked up surprised
and saw Tom, a doctoral student
of anatomy, standing next to her.
“Oh, I do some research
on this tiny critter”, she said.
It is a single-celled animal
from the Protozoa family,
called Tetrahymena, a biologist’s
“How can you be interested in
such a primitive creature? ” Tom asked.
“It must be a very boring object
“On the contrary.
This miniscule organism
is a fascinating creature
possessing astonishing attributes.
To insiders it offers more poetry
than your brain could imagine.”
“And why is that? ” Tom said.
His face wore a skeptical countenance.
“Well, mind you, in the 1950s
scientists discovered that
in many ways the battle of genders
among these cilia covered
little critters is far more complex
than among humans.”
“This is hard to believe”, Tom said.
“Yes, indeed. But imagine
that the Tetrahymena has
seven sexes to choose from.”
“You must be kidding.”
“Not at all. This is an established
scientific fact”, Ruth said.
“And the amazing story of
the Tetrahymena does not end
or start with the mystery of sex,
because this Lilliputian animal
also provides us with
compelling evidence about
the unity of all life on this planet.”
“And how is that? ”
“All life forms on Earth,
Including flowers, trees, amoebas,
Jellyfish, birds, tigers and you,
share a common setup:
They all combine amino acids
to make proteins and store
genetic information by using
deoxyribonucleic acid, DNA
molecules in encoding
the universal genetic code
by the same amino acids.”
“This leaves me quite indifferent”,
said Tom with a grin.
“I would get more excited if you
had informed me, for example,
that your critter can laugh and cry.”
“Well, as a matter of fact
perhaps it can. After all,
the Tetrahymena produces insulin,
acetylcholine, and endorphins,
as well as other neuropeptides
that we humans have
In our bodies. Thus, this primitive
and we humans
share the same
Now, bear in mind,
information exchange through
occur in similar ways
in all living organisms by means
of electrochemical processes,
by molecules of emotion.
that this one-celled critter,
similarly to us, also can be sad,
or excited and happy.'
Paul Hartal's Other Poems
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Poet's Notes about The Poem
For further reading:
1. Kathleen Collins, Editor, “Tetrahymena Thermophila”, Volume 109 (Methods in Cell Biology) , Academic Press,2012
2. Candace B. Pert, PhD, “Molecules of Emotion”, New York: Touchstone,1999
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