Why do rats squeak when fighting? - briefly
Rats emit high‑frequency squeals in combat to signal pain, submission, or aggression, which can discourage further attacks. The vocalizations also serve as an alarm to nearby conspecifics about the ongoing conflict.
Why do rats squeak when fighting? - in detail
Rats emit high‑pitched vocalizations during aggressive encounters as a multimodal signal that coordinates the fight and conveys the participants’ motivational state. The sounds arise from rapid vibration of the laryngeal muscles, which are activated by the sympathetic nervous system when the animal perceives a threat. This physiological response increases airflow and tension in the vocal cords, producing squeaks that can reach frequencies of 20–30 kHz, often beyond human hearing but detectable with ultrasonic equipment.
The acoustic emissions serve several specific purposes:
- Warning: The squeal alerts the opponent that the caller is prepared to escalate the conflict, potentially deterring further attack.
- Assessment: Frequency and amplitude correlate with the emitter’s size, health, and aggression level, allowing rivals to gauge relative strength without prolonged physical contact.
- Recruitment: In social colonies, distress calls can attract nearby conspecifics, either to intervene or to reinforce the dominant individual’s position.
- Stress regulation: Emission of vocalizations activates the rat’s own stress‑modulating pathways, reducing the likelihood of fatal injury by encouraging a quicker resolution.
Research using playback experiments demonstrates that rats respond differently to recorded squeaks depending on the acoustic parameters. Higher‑frequency, louder calls provoke avoidance or submissive postures, whereas lower‑frequency, softer calls elicit approach behaviors, indicating that the signal carries nuanced information about the caller’s intent.
Evolutionarily, vocalized aggression reduces the energetic cost of physical combat and minimizes the risk of severe wounds. By providing a rapid, non‑visual channel of communication, squeaking allows rats to negotiate dominance hierarchies efficiently within dense, low‑visibility burrow systems where visual cues are limited.
In summary, the squeaking observed during rat fights is a biologically programmed, ultrasonic vocal response that functions as a warning, assessment tool, social recruiter, and stress modulator, thereby facilitating conflict resolution and preserving colony stability.