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Abstract In complex social environments, individuals may interact with not only novel and familiar conspecifics but also kin and non-kin. The ability to distinguish between conspecific identities is crucial for most animals, yet how the brain processes conspecific type and how animals may alter behavior accordingly is not well known. We examined whether the communally breeding spiny mouse (Acomys cahirinus) responds differently to conspecifics that vary in novelty and kinship. In a group interaction test, we found that males can distinguish novel kin from novel non-kin, and preferentially spend time with novel kin over familiar kin and novel non-kin. To determine whether kinship and novelty status are differentially represented in the brain, we conducted immediate early gene tests, which revealed the dorsal, but not ventral, lateral septum differentially processes kinship. Neither region differentially processes social novelty. Further, males did not exhibit differences in prosocial behavior toward novel and familiar conspecifics but exhibited more prosocial behavior with novel kin than novel non-kin. These results suggest that communally breeding species may have evolved specialized neural circuitry to facilitate a bias to be more affiliative with kin, regardless of whether they are novel or familiar, potentially to promote prosocial behaviors, thereby facilitating group cohesion.
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This content will become publicly available on December 1, 2026
Oxytocin neural responses distinguish social novelty from familiarity but not kin from non‐kin in male spiny mice
Abstract In most species, individuals must be able to identify threats, peers, and potential mates to survive. The distinction of kin from non‐kin and novel conspecifics from familiars is essential to the successful categorization of these identities. Although oxytocin (OXT) signaling has been implicated in social recognition, little is known about the contributions of distinct OXT‐producing cell groups to distinguishing conspecific type. To determine whether OXT‐producing neuronal populations differentially respond to novelty or kinship status, we conducted immediate early gene tests in male spiny mice (Acomys dimidiatus), a communally breeding species that we previously showed distinguishes between novelty and kinship status. Immunohistochemical analysis of brain tissue revealed that the OXT cell populations in the paraventricular nucleus of the hypothalamus and the anterior hypothalamus did not differentially respond to the kinship or novelty status of same‐sex conspecifics. However, while OXT‐producing neurons in the bed nucleus of the stria terminalis did not distinguish between kin and non‐kin spiny mice, this cell group was more responsive to familiar than novel conspecifics. These results suggest that extrahypothalamic OXT neurons may be involved in aspects of processing the novelty status of a conspecific.
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- Award ID(s):
- 2310626
- PAR ID:
- 10676588
- Publisher / Repository:
- Journal of Neuroendocrinology
- Date Published:
- Journal Name:
- Journal of Neuroendocrinology
- Volume:
- 37
- Issue:
- 12
- ISSN:
- 0953-8194
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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