How do rats dig the ground? - briefly
Rats excavate soil by using their sharp incisors to loosen material while powerful forelimb muscles pull the loosened earth backward with their paws. Whiskers detect substrate consistency, and body movements compact the tunnel as digging progresses.
How do rats dig the ground? - in detail
Rats excavate soil using a combination of dental and limb adaptations that enable rapid substrate removal. Their continuously growing incisors cut through loose earth, while strong forelimb muscles and sharp claws loosen and lift material. The process proceeds in distinct phases.
The initial phase involves scratching the surface with foreclaws to create a shallow groove. Incisors then bite into the loosened soil, producing a series of small chips. Each chip is pushed backward by coordinated forelimb thrusts, allowing the animal to advance the tunnel front.
Subsequent phases develop a permanent burrow system. Rats alternate between forward digging and lateral expansion, forming branching galleries that serve for foraging, nesting, and escape routes. Ventilation shafts are incorporated to maintain airflow, reducing carbon‑dioxide buildup.
Soil characteristics strongly influence digging efficiency. Sandy or loamy substrates require fewer strokes per centimeter of advance than compact clay, where additional muscular effort and increased claw penetration are necessary. Moisture content affects cohesion; moderately moist soil provides optimal resistance for claw traction without excessive clumping.
Typical excavation rates reach up to 150 g of soil per hour for medium‑sized individuals, with some reports of daily displacement exceeding several kilograms. «Rats are capable of moving several kilograms of soil per day», illustrating their high energetic investment in burrow construction.
The resulting network consists of primary tunnels 5–15 cm in diameter, extending 1–3 m in length, with secondary chambers for food storage and rearing. Regular maintenance—removing debris, reinforcing walls, and adjusting tunnel geometry—ensures structural stability throughout the rat’s lifespan.