Fighting through the heat: How male aggression influences demography under recurrent heatwaves

Sexual selection is a potent evolutionary force that can enhance adaptation and reduce mutational load, while simultaneously reducing survival, or cause sexual conflict that reduces fitness for one or both sexes. Many populations today face not only gradual environmental changes but also extreme, short-term stress events. The combined effects of sexual and environmental selection on population demography during and after such events remain poorly understood, even though such combined effects could be crucial for the persistence of small, endangered populations under climate change. This dataset derives from a multi-generational experimental evolution study investigating how sexual selection interacts with thermal stress to shape population demography in the male-dimorphic soil mite Sancassania berlesei. It includes detailed generational records from 42 populations subjected to a factorial design manipulating sexual selection intensity (via pheromone-induced morph suppression) and e..., , # Fighting Through the Heat: How Male Aggression Influences Demography Under Recurrent Heatwaves

Dataset DOI: [10.5061/dryad.1jwstqk6h](10.5061/dryad.1jwstqk6h)

## Description of the data and file structure

This dataset originates from a multi-generational experimental evolution study designed to test how male aggression, manipulated via pheromonal control of male morphs, influences population survival and extinction risk under recurrent heat stress. The focal species is *Sancassania berlesei*, a male-dimorphic soil mite. Forty-two replicate populations were tracked over eight generations under a 2×2 factorial design:

- **Pheromone regime**: Control (normal fighter prevalence) vs. Treatment (reduced fighter prevalence via pheromonal cues)

- **Temperature regime**: Stable (23°C) vs. Heatwave (45-hour exposure, escalating from 34°C to 38°C)

### Files and variables

#### File: SS_heat_demography_dryad.xlsx

| **Sheet** ...,