How do mice drink? - briefly
Mice ingest liquids by rapidly flicking their tongues, pulling a thin film of water into the mouth. The tongue tip contacts the liquid surface, then retracts, drawing the fluid upward through surface tension.
How do mice drink? - in detail
Mice obtain liquids through a rapid licking motion that creates a transient negative pressure between the tongue and the oral cavity. The tip of the tongue is narrow and flexible, allowing it to penetrate the liquid surface with each contact. When the tongue retracts, it pulls a thin column of fluid upward, which is then swallowed by a brief contraction of the pharyngeal muscles.
Key anatomical features that enable this process include:
- A flattened, elongated tongue tip that minimizes surface tension disruption.
- Strong, fast‑acting intrinsic tongue muscles that produce high‑frequency strokes (up to 10 – 12 Hz).
- A highly mobile mandible that opens and closes synchronously with tongue movement, maintaining a sealed oral cavity.
- A well‑developed submandibular gland that secretes saliva to lubricate the tongue and reduce friction.
The sequence of actions during a drinking bout is:
- Tongue tip contacts the liquid surface.
- Rapid retraction creates a pressure differential, drawing fluid along the tongue.
- The tongue lifts the fluid column toward the mouth.
- Pharyngeal muscles contract, moving the fluid into the esophagus.
- The cycle repeats, producing a continuous stream of intake.
Observations from high‑speed video recordings show that each lick lasts approximately 80 ms, and the total volume per lick averages 0.1 µL. This efficiency compensates for the mouse’s small body size and high metabolic rate, ensuring adequate hydration with minimal time spent at the water source.