Organisms can survive and reproduce even with homeotic gene mutations that produce differences in body shape. This means that homeotic mutations can be an effective means for evolutionary change.

For example, in a mammal, a single homeotic mutation might produce an arm that is shorter, or longer, or broader. Regardless, it will probably still look and work like an arm.

A change in body shape might lead to an advantage for an organism. For example, the mutation may allow it to capture food more effectively or be more attractive in some way. If this is the case, then the mutant organism may have greater reproductive fitness. Its genes may be preferentially passed along to the next generation, thus influencing the course of evolution.