Thor's Day: Two ways of looking at the chicken in the egg

By Morris Dean

[Originally published December 20, 2012]

The following science story came to my attention [the day I originally wrote this]:

It was for quite some time thought that when chickens hatched and immediately began pecking the ground for food, this behavior must have been instinctive. In the 1920s, a Chinese researcher named Zing-Yang Kuo made a remarkable set of observations on the developing chick egg that overturned this idea – and many similar ones.

Using a technique of elegant simplicity, he found that rubbing heated Vaseline on a chicken egg caused it to become transparent enough so that he could see the embryo inside without disturbing it. In this way, he was able to make detailed observations of the chick's development, from fertilization to hatching. One of his observations was that in order for the growing embryo to fit properly in the egg, the neck is bent over the chest in such a way that the head rests on the chest just where the developing heart is encased. As the heart begins beating, the head of the chicken is moved up and down in a manner that precisely mimics the movement that will be used later for pecking the ground. Thus the "innate" pecking behavior that the chicken appears to know miraculously upon birth has, in fact, been practiced for more than a week within the egg. [–"The Name Game," by Stuart Firestein, in This Will Make You Smarter: New Scientific Concepts to Improve Your Thinking (2012), pp. 62-63]

When it comes to understanding the inner significance of the story, there are two ways of looking at it:

TIGER, tiger, burning bright
In the forests of the night,
What immortal hand or eye
Could frame thy fearful symmetry?
...
When the stars threw down their spears,
And water'd heaven with their tears,
Did He smile His work to see?
Did He who made the lamb make thee?
                    –William Blake (1757-1827), "The Tiger"


Chicken, chicken, turning tight
In Zing-Yang's careful, questing sight,
In what twists of physics lie
The secrets of your coming by?

When after many million years
Of nature's restless turning gears,
The same process that brought forth thee
Produced these lines—and me.

Copyright © 2015 by Morris Dean