Age-old chicken vs. egg question has differing opinions

“Which came first, the chicken or the egg?” asked sixth-graders from Maureen Petricca's class at Nerge Elementary School in Roselle.

In 300 B.C., Ancient Greek philosophers were scratching their heads about chickens and eggs.

Aristotle pondered the well known tail-chaser about order and origins, recognizing that both the chicken and the egg could feather their nests with bragging rights to being first. Birds come from eggs, but an egg comes from a bird, he asserted. More than 300 years later, Plutarch, another famous Greek philosopher still searching for an answer to the puzzler, made the philosophical leap between this question and the greater mystery of the origins of the world.

So, which came first, the chicken or the egg?

Dr. Jerry Coyne, University of Chicago professor, Department of Ecology and Evolution, took the egg's side.

“If you take it literally, the egg evolved before the chicken, because chickens evolved from dinosaurs that were already laying eggs. And reptiles evolved from early amphibians, which had themselves evolved to lay eggs,” Coyne said.

The chicken's first, according to research cited by Dr. Yvette Johnson-Walker, a veterinarian at the University of Illinois College of Veterinary Medicine.

“In 2010, an English research team concluded that the chicken had to have come first when they identified a chicken protein necessary for the production of the chicken egg shell,” Johnson-Walker said.

Famous physicist Steven Hawking bets his nest egg on the egg. Many life-forms begin with eggs, including fish, reptiles, birds, insects, mammals and some plants.

Professor James R. Stewart, reproductive physiologist at East Tennessee State University, also hatches the idea that it was the egg first. An article in Popsci.com explains Dr. Stewart's theory that a four-limbed reptile evolved 150 million years ago, which produced amniotic eggs with yolks. Like Dr. Coyne said, birds evolved from oviparous reptiles.

In 2006 a panel that included a philosopher, a geneticist and farmer supported the egg, sort of. Their answer was the egg came first, although a prototype for the chicken laid the egg, not the actual chicken.

Dr. Johnson-Walker took a more philosophic approach to this age-old question. Answering the question with a question, she connected the chicken and egg to the one about Tootsie Pops: “How many licks does it take to get to the center? The world may never know.” What do you think is the answer?

Chickens and eggs require special care and nurturing. Learn more about caring for all types of animals at the annual Vet Med Open House from 10 a.m. to 4 p.m. Sunday, Oct. 6, sponsored by the University of Illinois College of Veterinary Medicine and held at its Urbana facilities.

The public is invited to this free event, which will feature more than 40 exhibits hosted by students of the state's only veterinary medical program. Exhibits include cow milking, small animal rehabilitation and demonstrations.

There are many hands-on activities for kids, and prospective veterinarians can learn about applying to veterinary college. No registration is needed. Directions to the open house and a list of exhibits are online at www.vetmed.illinois.edu/openhouse.

For details, call the University of Illinois Public Engagement Office, (217) 333-2761.