1st. ( biology) In nature living things evolve through changes in their DNA. In an animal, DNA from a male sperm cell and a female Ovum meet and combine to form a Zygote, In every animal, every cell contains exactly the same DNA, and the DNA comes from the Zygote. Chicken evolved from non-chicken tthrough small changes caused by the mixing of male and female DNA or mutation to the DNA that produced the Zygote. These changes and mutations created a new Zygote. That is two non-chicken mated, and in their new Zygote contained the mutation/s that produced the 1st true chicken. The Zygote cell is the only place where DNA mutation would produce a new animal, and the Zygote cell is housed in the chicken's egg. So Biological speaking, the egg must have come 1st. 2nd. (Phylosophy/Theology)And God said, let the waters bring forth abundantly the moving creatures that hath life, fowl that may fly above the earth in the open firmanet of heaven. And God created every living creature that moveth, and God saw that it was good. And God blessed them, saying. Be fruitful and multiply and let the fowl multiply in the earth. Therefore a literal historic account of Genesis, would place the chicken before the egg. therefore, depending on wether you believe in a scientic or theological approach: There is no wrong answer to which came first...