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We examined side preferences in trunk and forefoot movement during feeding in a wild population of Asian elephants. Trunk sweeping movements to pluck/uproot/gather vegetation and forefoot scuffing movements to uproot vegetation were scored in 206 individuals. We found a much stronger side preference in trunk use than in forefoot use, supporting a modified task complexity hypothesis. The forefoot and trunk appeared to be coordinated while feeding and, among individuals that had significant forefoot preferences, the proportion of right forefoot use was higher among right trunkers than left trunkers. Trunk and forefoot preferences were not dependent on individuals' social associates, and trunk preferences were also not dependent on feeding associates. There was a significant effect of individual identity on forefoot preference strength but no population-level side preference in trunk or forefoot movement, suggesting no dominant eye control over the task, which might be true of feeding-related foot movement in other herbivores also. There was no effect of age or sex on trunk or forefoot side preference or strength. The onset of trunk side preference, however, was very early compared with that observed in other species studied and calls for a comparison of the ontogeny of side preferences in precocial and altricial species. Based on 57 mother-offspring pairs, we found that offspring trunk side preferences were independent of their mothers' preferences, suggesting that these preferences are not maternally inherited.

Musth is an annual, asynchronous, rut-like phenomenon observed in male elephants. We examined whether musth is a roving strategy, and whether musth provides a temporary advantage to young males through increased access to female groups. We collected long-term data on the musth status, associations, and locations of male elephants in the Kabini population in southern India. We sighted older males more frequently in musth than younger males. We found a greater turnover of musth than non-musth males in the study area, suggesting that musth is a roving strategy, enabling males to travel widely and away from their non-musth range. Contrary to our expectation, young (15–30 years old) males spent a smaller proportion of their musth time than their non-musth time associating with females, and associated with similarly sized female groups irrespective of musth status. Old (> 30 years old) males spent only a slightly higher proportion of their musth time than non-musth time with female groups, but associated with larger female groups during musth. Although old males in musth associated with young non-musth males more often in the presence, than in the absence, of females, young males in musth were never sighted with old non-musth males in the presence of females. Therefore, the payoff from musth, as a strategy to gain access to females, was age-specific; musth in old males allowed for increased association with females, while musth in young males restricted their access to females. There was no spatial avoidance between musth and non-musth adult males at scales larger than immediate associations. Our results suggest that musth seems to be primarily a roving strategy for old males to find and associate with females and not a strategy for young males to gain a temporary advantage over old males, within the broad age-classes that we examined.

We present a detailed study of male associations in the Asian elephant, using 6 years of data on identified, non-musth males. Adult males spent greater proportions of their time solitarily than in mixed-sex or in all-male groups. Old (over 30 years) males were sighted more frequently with their age-peers and less frequently with young (15–30 years) males than expected at random in all-male groups. Young males were not sighted more frequently with old males than with young males, and did not disproportionately initiate associations with old males. These results suggest that male associations, in the absence of females, may allow for old non-musth males to test strengths against age-peers. Social learning from older individuals did not seem to be important in male associations, unlike that observed in the African savannah elephant. We also found a constraint on the sizes of all-male groups, similar to that seen in female groups in our study population, and all-male groups were rarer and smaller than those in African savannah elephant. Although male associations were weak, most males had a significant top associate, with whom their association was the strongest, in female absence. In mixed-sex groups, male associations occurred at random, suggesting that males were tracking female groups independently. Differences in male social organization from that of the related African savannah elephant that occupies a similar niche possibly arise from differences in ecology.