U. Gabathuler et al., THE SOCIAL-STRUCTURE AND DOMINANCE HIERARCHY OF THE MASHONA MOLE-RAT,CRYPTOMYS DARLINGI (RODENTIA, BATHYERGIDAE) FROM ZIMBABWE, Journal of zoology, 240, 1996, pp. 221-231
Cryptomys darlingi is a social subterranean rodent mole which inhabits
the mesic regions of south-eastern and central Africa. Mashona mole-r
ats live in small colonies (5-9 animals) in which reproduction is norm
ally restricted to the largest male and female in the colony. The nonr
eproductive members in a mature colony cannot be placed into clearly d
efined work-related groups based on body mass. The dominance hierarchy
of a young colony was found to be linear, with a value of 1.00 calcul
ated from Landau's linearity index, while that of a mature colony of n
ine mole-rats was almost linear (0.77). Dominance was found to be rela
ted to gender in the mature colony, with males more dominant than fema
les, and to age in the young colony. The reproductive mole-rats are th
e dominant animals within their respective genders. Dominance appears
to correlate positively with body mass (rs = 0.77 in the mature colony
and rs = 0.93 in the young colony). Popularity studies show that smal
ler animals and females tend to be more popular than the larger massed
individuals or males. In the mature colony which contained predominan
tly adult animals, the reproductive pair was among the least popular.
While in the young colony, composed predominantly of sub-adult and juv
enile animals, the reproductive pair was the most popular. Social orga
nization within Mashona mole-rat colonies is compared with other south
ern African Cryptomys species.