I have only 4 chickens, 1 Wellsummer, 2 Brahmas and 1 Easteregger. It is very easy to identify which birds layed which eggs. The two Brahmas lay a large med brown egg. The Welsummer lays terracotta speckled eggs and the Easteregger layed longer more pointed pinkish eggs. They have all been laying since late last summer. Well... I noticed that the Easteregger hadn't layed any eggs for about a week. Then, I opened the nesting box one day and there was a lovely green egg. She now lays a green egg about every 2 days. I thought whatever the color was to begin with, it would always remain that color. I am so pleased that she now lays green eggs because they are so different. I love to give them to friends and watch their faces...