* Moisture: Isopods need a moist environment to survive. Under rocks, they find a humid microclimate that prevents them from drying out.
* Protection: The underside of rocks provides shelter from predators like birds, lizards, and even larger insects.
* Food: Isopods are detritivores, which means they feed on decaying organic matter. Under rocks, they find a plentiful supply of decaying leaves, wood, and other debris.
* Temperature regulation: Rocks can help regulate temperature, providing a cooler environment in the heat and a warmer environment in the cold.
In short, the space under rocks provides isopods with a safe, moist, and food-rich environment that meets their basic needs for survival.