What three factors trigger a subterranean swarm?

In understanding the factors that trigger a subterranean swarm, it is important to recognize the significance of environmental conditions that influence insect behavior, particularly for species that are known to swarm from underground habitats.

The correct factors are closely associated with humidity and temperature because both are key elements that affect the activity levels of many subterranean insects. High humidity levels can create a conducive environment for swarming, as these insects often require moist conditions for their survival and reproduction. Additionally, temperature plays a vital role, as certain thresholds can prompt the insects to leave their burrows en masse.

Light is another important factor, particularly in triggering swarming behavior in various insect species. While subterranean species may be less influenced by light compared to surface-dwelling species, it can still be a contributing factor when they emerge from their underground habitats.

The other factors mentioned, such as soil type and food availability, are more related to long-term habitat suitability rather than immediate triggers for a swarm event. Soil type can influence the colonization and growth of a population, while food availability impacts overall growth and reproduction. However, they are not immediate stimuli that lead directly to the occurrence of a swarm. Thus, the combination of humidity, temperature, and light captures the essential elements that actively