I'm a new chicken Mom so I know I have a lot to learn. We have 5 RIRs and 3 Americanas. We get up to 6 or 7 eggs a day. Five are brown and up to 2 are green. I'm assuming one of my Americanas is not laying. Could I have a rooster and just do not know it? Also, in about 1 in every 3 eggs, there is a small dark spot on the yoke of the egg. What does this mean? Once I found a gross looking thing attached to the yoke and have no idea what it was. It was easily removed and the rest of the egg looked fine. Out of a hundred eggs, this has only happened once (the gross thing I cannot even adequately describe.) I'm so confused. Any advise on what a fertilized egg looks like, if this is the case with my flock.