I believe it all started as simply as cells. The spermatozoon and the ovum somehow came into existence (I'm not saying how *cough*GOD*cough* ^_^) and during the impregnation of the ovum, the cell split and a male rooster and a female hen were born, most likely in an environment capable of fetal incubation. In fact, this could apply to all species born on our planet, if people can believe that the universe just popped into existence, why not all life on earth? (*cough*GOD*cough* :lol: )