Unyielding rock can be simultaneously inhibitor or constraint as well as a castle or protector. Here Delosperma carolinense makes the most of its container-like home; not called a klipvygie (stone mesemb) for nothing.

Whatever nature provides is taken up by some species as its evolutionary challenge and destiny, becoming painstakingly over many generations what fits with the available feature and thus be the fittest for its circumstances (Smith, et al, 1998; iNaturalist).