Dimorphism refers to the existence of two distinct forms or shapes within a species. It typically refers to the presence of noticeable physical differences between males and females.
This aspect must be evaluated in association with the pronounced body - size variation within the sample, which implies marked differences between age ranges and a considerable degree of sexual dimorphism in Au. (elifesciences.org)
This seal shows extreme sexual dimorphism in size, seemingly the largest of any mammal by mass, with the males typically five to six times heavier than the females. (en.wikipedia.org)
Regardless, these footprints do expand the upper limit of size in (presumably) A. afarensis, and offer strong support for arguments favoring strong sexual size dimorphism in this extinct species. (elifesciences.org)