 Santos suggests that such a view of things is indicated by modern cellular and developmental biology, but the theoretical descriptions he cites (e.g., 2015a: 30–32; 2015b: 439–440) appear to be consistent with the other metaphysical frameworks described in the previous two sections. The issue of whether enduring structured entities are essential or inessential to the broad frameworks embraced by the special sciences is a large issue that cannot be discussed here.