Organism build tissues that seemingly never use and serve no purpose. Many animals build tissues and structures they do not appear to use, and then they disappear. Computational simulation of evolution suggests that organisms jump through these extra hoops to avoid disrupting a developmental process that works. In a developing embryo, each new structure is built in a delicate environment that consists of everything that has already being developed. Therefore, mutations that alter that environment, such as eliminating a structure, can thus disrupt later stages of development. Structure that are actually not used, may set the stage for other functional tissues to grow properly. Newly developed traits tend to get added at the end of development, because there is less risk of disrupting anything important. Thus, this indicates that developmental order does resemble evolutionary order.
