So I've learned that the CXs are cornish males and white rock females, but if I wanted to rear my own freedom ranger chicks, what kind of cross would that be? Are they a simple cross of two breeds, or is it more difficult than that? For that matter are the CXs a simple cross of two breeds, or a cross of two breeds that have been genetically selected time and again? Also, since I'm new and still researching, I've hinted around at this question already, but.... CXs seem to have issues with heat tolerance and this is going to be a long, hot summer. Someone said that the FRs don't have the same issues with heat. Can someone give me information about how well(or not) the FRs cope with heat into the 90s and higher.