Increased Demographic Turnover and Isolation Precede Social Fragmentation in Asian Elephants

Madsen, A.; Pushpakumara, T. V.; Weerathunga, U. S.; Weerakoon, D. K.; de Silva, S.

doi:10.64898/2026.09.24.754174

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bioRxiv · 10.64898/2026.09.24.754174

Increased Demographic Turnover and Isolation Precede Social Fragmentation in Asian Elephants

Madsen, A.·Pushpakumara, T. V.·Weerathunga, U. S.·Weerakoon, D. K.·de Silva, S.

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Abstract

Humans and other animals live in interconnected social communities that are essential for survival and well-being. In principle, social communities can persist despite changes in constituent members. However, gradually accumulating changes to membership could push systems past critical thresholds into alternate states. We investigated social network dynamics for 443 wild female Asian elephants over 12 years by tracking community membership and structure. Following accumulated demographic turnover, networks fractured into smaller and more isolated social communities. Connections were changed not only due to turnover of members but also rewired among remaining individuals. This provides the first empirical evidence of a social network state change in a long-lived mammal.

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Madsen, A., Pushpakumara, T. V., Weerathunga, U. S., Weerakoon, D. K., de Silva, S.. 2026-09-25. Increased Demographic Turnover and Isolation Precede Social Fragmentation in Asian Elephants. https://doi.org/10.64898/2026.09.24.754174

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