I bought two RIR day old chicks from a feed store. I paid a higher price for them because the owner said she paid extra from the hatchery to have them sexed as hens. 1 has the typical stripe on top of its head, the other doesn't have one--that is the one my daughter picked. It is more light red compared to the brown one. After setting up in the cage, I put both in. Within minutes, the light colored one kept jumping out. So I put the top on it (it is a Med size dog portable carrier) and it tried to escape through the front gate. I put cardboard inside to block half so heat lamp could work. Well, since I couldn't get the temp up to 90 degrees, I had to think of a new living arrangement. So I found a box about 6" higher than the last one. Well, it jumped up on top. So I found a box 2-1/2 feet high. It is still trying to jump out. The temp is perfect at one end, giving them freedom to move to the other side for cooler temp, food, and water. I am worried because I have two 4 or 5 week RIR chicks in another cage that one didn't try jumping out until it was 3 wks old. That one I suspect is a rooster. It has a larger comb than the other, larger, and is more brave. When I clean the cage several times during the day, it will come to my hand and gently peck the glove, eat, and drink water ignoring me. While the other will stay at the far end until I am finished. My fear is the jumping chick is a rooster and not a hen. Anyone who has raised several RIR find that the jumping chick is a rooster? Please let me know as I am thinking of returning it to exchange for another. The reason I bought two more was to replace the older chick I suspect is a rooster. Will find him a home once confirmed. Where I live, I can not have a rooster otherwise it wouldn't be a problem. Please let me know. Thanks.