I have five Ameraucanas between 13 and 14 weeks old. A grey/blue one has the largest comb. Of the other 4, none has a comb anywhere near the size of the grey/blue one. However, some are starting to develop the longer tail feathers I associate with cockerels. I'm still a month from having to cull, but I am wondering if I should rely more on the comb or the tail feathers to guess at the gender. I know, pictures would help. I have to get a new camera.