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al. 1997; Woodroffe and Macdonald 1995b). Rather, these social advantages
appear to be secondary benefits derived from, but not fully explaining, their
group living habit. On one hand, this spatial congruity is distinct from the
aggregation of jackals or bears at a carcass or salmon leap, and perhaps even
distinct from the community of antagonistic monogamous pairs of maras
(
Dolichotis patagonum
) at a communal breeding den (Taber and Macdonald
1992). On the other hand, the badger spatial group is equally distinct from the
social group of African wild dogs, whose cooperative hunting or collective
defense of prey leads sociologically to per capita advantage (Creel 1997; see
also Packer and Caro 1997). Furthermore, the jackals meeting at a carcass may
come from many different territories, but they may nonetheless meet fre-
quently and have well-established social relationships. Indeed, as Macdonald
and Courtenay (1996) showed, neighboring territorial canids may even be
bonded by familial ties (see also Evans et al. 1989 for genetic evidence of links
between adjoining groups of badgers). It is therefore difficult to formulate a
precise definition, and social group risks becoming a nebulous concept. A
social group constitutes a network of variously close affiliations: closely con-
nected subclusters of individuals comprising subgroups, and groups connected
by primary links between core individuals defined as supergroups. Clusters
preferentially and mutually exchanging services, support, or aid may be said to
display friendships (Smuts 1985), and where clusters act in concert against
others we may define them as coalitions. Of course, the benefits an individual
can accrue through associations are not always mutually beneficial, and Kraft
et al. (1994) designed a diving-for-food experiment to illustrate theft in rat
society. Rats were trained to dive into water in order to obtain food from
another compartment. All individuals learned to dive; however, those that
were able to steal effectively from their diving companions often opted for this
less arduous means of securing food.
Macdonald et al. (1987) distinguished a hierarchy of questions to be tack-
led in quantifying cat sociality, and these could be adapted to a simple descrip-
tion of any society. First, on the basis of their individual comings and goings,
what are the probabilities of a given dyad of cats being available to each other
for interaction? Second, when they are simultaneously present, what proxim-
ity do they maintain? Third, what is the overall frequency of interactions
between them, and how does that translate to a rate per unit time in associa-
tion? Fourth, what are the qualities of interaction? Fifth, what are the direc-
tions of flow from initiator to recipient for each type of interaction?
First, indices of association raise the question of what level of proximity
constitutes being together, and the answer may vary between species from
