But these genetic mutations must occur in the zygote or initial cell, so a creature very similar to a chicken (which we could call a porto-chicken would have mated with another proto-chicken and because of a small genetic mutation created the first chicken, which grew in an egg.但這些基因變化必須發生在受精卵或原始細胞,所以一個很接近雞的生物 (我們稱之為「原型雞」),要與另一隻原型雞配對,同時因為微小的基因變化,而創造出第一隻雞,而它由蛋所生。