 First, the production of an outcome F is supposed to be robust. In Shea’s terminology, this means that F is produced (a) “in response to a range of different inputs” and (b) “in a range of different relevant external conditions” (Shea 2018, 55). Depending on the ranges in question, the production of F can be described as more or less robust. Of particular importance is clause (a) of the definition, since it is demanding enough to exclude certain outcomes completely. If, for example, a plant closes its flowers only in response to a change in temperature, then the flower-closing behavior does not qualify as a robust outcome. However, if the plant also closes its flowers in response to some other input, e.g. a change in light levels, then the behavior does count as (minimally) robust (Shea 2018, 213–214).