rationalskepticism.org

That's interesting because this means (at least some of the) genes involved in heart development were already present and used for development of other tissues before hearts and circulatory systems started evolving. Which simply mean the later systems were diversifications of earlier systems, not new complete systems that developed by chance, mutation by mutation. That gene could have undergone duplication and the duplicate left open for mutation and co-option into circulatory development, or another related tissue.
Am I getting this right?