Biology subjects

Nandini, S.

Publications and source records attributed to Nandini, S..

3 recordsLinked to original sources

bioRxiv2026

Calves function as social magnets in a species with high fission-fusion dynamics, the Asian elephant

Individuals living in fission-fusion societies may face unique challenges in maintaining social relationships, as the repeated fission of social units can limit opportunities for social interaction. However, the presence of young offspring may often necessitate cooperation among individuals. To understand whether offspring promote sociality in fission-fusion species, we studied wild Asian elephants (Elephas maximus) in southern India. Using nearly 5900 female group sightings collected over 9 years, we tested whether calf presence predicted female group size and associations. The numbers of adult, young adult, and subadult females in groups were 2-2.5-fold higher in calf presence than absence, which may facilitate collective defence of calves. Furthermore, the number of females without their own dependent offspring, who often provide allomaternal care, was also higher in calf presence than absence. Social network analysis revealed that adult females formed more numerous and stronger associations in calf presence than absence, which may facilitate consistent allomaternal care. Our results thus suggest that the need to protect calves and to provide allomaternal care likely promote sociality among female elephants. We propose that dependent offspring may function as social ties in fission-fusion species, contingent upon the prevailing conditions and the socioecological pressures that have shaped their social systems.

animal behavior and cognition↗

bioRxiv2025

Female Asian elephant clans have age-based order but weak dominance resolution

The variation in dominance relationships in group-living species is often interpreted through socioecological frameworks that link social structures to resource-risk distributions. However, in elephants, such inferences are hindered by a lack of comparable assessments of within-group dominance in different species. To advance our understanding of elephant socioecology, we present here, the first study on agonistic and dominance relationships within female Asian elephant clans (most inclusive social groups), and compare our results with those from African savannah elephants. By analysing agonistic interactions, and dominance and association networks based on over four years of observations of five clans, we show that Asian elephants have a resolved but weakly structured within-clan dominance order. Female dyads showed unidirectionality, but triad motif structures of dominance networks suggested resolved dominance only in some clans. Older females were more dominant although there were moderate levels of reversals against age-based order and age difference did not dampen dyadic conflict. Neither older age nor dominant status conferred more central status in the female association network. Weak dominance resolution and the effects of age contrast with the stronger dominance and age-based order found in African savannah elephants. We identify potential socioecological and demographic explanations of female dominance in elephants.

animal behavior and cognition↗

bioRxiv2018

Effects of male age and female presence on male associations in a large, polygynous mammal in southern India

We present a detailed study of male associations in a roving species, the Asian elephant, using six years of data on identified, nonmusth 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, primarily allow for old nonmusth 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 African savannah elephants. We also found a constraint on the sizes of all-male groups, similar to that seen in female groups in our study population, and with male group sizes being smaller than that of African savannah elephants. However, most males had a significant top associate in female absence. In mixed-sex groups, male associations occurred at random, suggesting that males were tracking female groups independently. Thus, we find some differences in male social organisation compared to the phylogenetically related African savannah elephant that occupies a similar niche, and suggest that ecological factors might have shaped the differences in these male societies.Competing Interest StatementThe authors have declared no competing interest.View Full Text

animal behavior and cognition↗