Figure 3.

Familial composition of the modal and adjacent size classes (defined as log₂ units 4–6) as a function of latitude. The contribution of individual families changes with latitude; e.g., Veneridae and Arcidae are important in the lower latitudes whereas other families, such as Astartidae and Sareptidae, are more important at high latitudes. Thus, the similarities of the provincial SFDs are not the result of phylogenetic effects, such as the presence of a few species-rich and latitudinally widespread families.