title: Fiat or bona fide boundary--a matter of granular perspective.
abstract: BACKGROUND
  Distinguishing bona fide (i.e. natural) and fiat (i.e. artificial) physical boundaries plays a key role for distinguishing natural from artificial material entities and is thus relevant to any scientific formal foundational top-level ontology, as for instance the Basic Formal Ontology (BFO). In BFO, the distinction is essential for demarcating two foundational categories of material entity: object and fiat object part. The commonly used basis for demarcating bona fide from fiat boundary refers to two criteria: (i) intrinsic qualities of the boundary bearers (i.e. spatial/physical discontinuity, qualitative heterogeneity) and (ii) mind-independent existence of the boundary. The resulting distinction of bona fide and fiat boundaries is considered to be categorial and exhaustive.
  
  
  RESULTS
  By Referring to various examples from biology, we demonstrate that the hitherto used distinction of boundaries is not categorial: (i) spatial/physical discontinuity is a matter of scale and the differentiation of bona fide and fiat boundaries is thus granularity-dependent, and (ii) this differentiation is not absolute, but comes in degrees. By reducing the demarcation criteria to mind-independence and by also considering dispositions and historical relations of the bearers of boundaries, instead of only considering their spatio-structural properties, we demonstrate with various examples that spatio-structurally fiat boundaries can nevertheless be mind-independent and in this sense bona fide.
  
  
  CONCLUSIONS
  We argue that the ontological status of a given boundary is perspective-dependent and that the strictly spatio-structural demarcation criteria follow a static perspective that is ignorant of causality and the dynamics of reality. Based on a distinction of several ontologically independent perspectives, we suggest different types of boundaries and corresponding material entities, including boundaries based on function (locomotion, physiology, ecology, development, reproduction) and common history (development, heredity, evolution). We argue that for each perspective one can differentiate respective bona fide from fiat boundaries.
authors.affiliation: Institut für Evolutionsbiologie und Ökologie, Universität Bonn, Bonn, Germany. lars.m.vogt@gmail.com
authors.forename: Lars
authors.initials: L
authors.lastname: Vogt
authors.forename: Peter
authors.initials: P
authors.lastname: Grobe
authors.forename: Björn
authors.initials: B
authors.lastname: Quast
authors.forename: Thomas
authors.initials: T
authors.lastname: Bartolomaeus
mesh_terms: D005075:Biological Evolution; D015350:Contrast Sensitivity / Q000502:physiology*; D006801:Humans; D014796:Visual Perception / Q000502:physiology*