What breed and pullet or cockerel for the 2 darker chicks in the photos? Both are 4 weeks old today. Was told the black chick is a black sex link pullet, but I have another one that is the same age, and it has a longer tail and less developed comb than this one. Could this be a cockerel? Thoughts on the other dark chick? I suspect that one is a pullet, but any idea on the breed?