Chicken vs. Egg
The eternal question: Which came first?
The answer is a semantic one: What is your definition of “egg”?
Egg: A gestation device laid by birds, fish, and reptiles.
The dinosaurs laid eggs, therefore, the egg pre-dates the chicken.
Egg: A gestation device laid by birds.
Other birds pre-dated the chicken, therefore, the egg came first.
What about a “Chicken Egg”?
What IS a chicken egg?
If you define a chicken egg as: An egg LAID BY a chicken, then:
The first “chicken egg” had to follow the first chicken in order to be laid by one, thus, the chicken came first. We assume the first CHICKEN came from the egg of some other slightly different bird variety that was NOT a chicken.
If you define a chicken egg as: An egg FROM WHICH a chicken is hatched, then:
Some other slightly different bird variety laid the first CHICKEN EGG, which subsequently produced the first CHICKEN. Thus, the chicken egg came first.