Another sign of maturity is to see a pattern of knowledge building from a series of experiments. This reflects the discipline’s ability to build on prior work (knowledge, models, experiments). There are various ways of viewing this. We can ask if the study was an isolated eventj if it led to other studies that made use of the information obtained from this particular study. We can ask if studies have been replicated under similar or differing conditions. We can ask if this building of knowledge exists in one research group or environmen, or has spread to others, i.e., researchers are building on each other’s work.