The neural basis of species-specific defensive behaviour in Peromyscus mice

Evading imminent predator threat is critical for survival. Effective defensive strategies can vary, even between closely related species. However, the neural basis of such species-specific behaviours is still poorly understood. Here we find that two sister species of deer mice (genus Peromyscus) show different responses to the same looming stimulus: P. maniculatus, which occupies densely vegetated habitats, predominantly escapes, while the open field specialist, P. polionotus, briefly freezes. This difference arises from species-specific escape thresholds, is largely context-independent, and can be triggered by both visual and auditory threat stimuli. Using immunohistochemistry and electrophysiological recordings, we find that although visual threat activates the superior colliculus in both species, the role of the dorsal periaqueductal gray (dPAG) in driving behaviour differs. While dPAG activity scales with running speed in P. maniculatus, neural activity in the dPAG of P. polionotus ..., , # The neural basis of species-specific defensive behaviour in Peromyscus mice

Dataset DOI: [10.5061/dryad.q2bvq83xc](10.5061/dryad.q2bvq83xc)

This repository contains the source data for the paper *Baier, Reinhard et al. (2025) Nature*, in which we found that two sister species of *Peromyscus* (deer mice) show different reactions to overhead approaching danger. We correlated these differences in behaviour with differential evolution of the dorsal periaqueductal gray (dPAG), which mediates escape in one species, but not in the other. This was confirmed with cFOS analysis, electrophysiological recordings, opto- and chemogenetic manipulations. Here we provide the data that replicates the main figure panels of the paper, specifically: (1) The speed traces to replicate the species differences of Figure 1E, (2) the speed traces to replicate the different modalities of Figure 2, (3) the mean speed and number of cells to replicate the cFos correlation with behaviour of Figure 3B, D-G and I, (...,