How do mice drink water? - briefly
Mice lap water by flicking the tip of their tongue against the liquid surface, forming a thin column that they draw upward with suction. This rapid licking action allows them to ingest sufficient fluid in a few brief strokes.
How do mice drink water? - in detail
Mice acquire liquid primarily through rapid tongue movements that generate a suction force. The tongue tip is narrow and flexible, allowing it to dip into the water surface and withdraw at a high speed. As the tongue retracts, a negative pressure is created within the oral cavity, pulling water up the narrow channel formed by the tongue and the lower jaw. This mechanism, sometimes described as “capillary suction,” enables the animal to lift droplets that are smaller than the tongue’s diameter.
Key anatomical features that facilitate this process include:
- A highly vascularized, muscular tongue capable of oscillating up to 10 times per second.
- A recessed oral cavity that expands during retraction, enhancing pressure differentials.
- Sharp, curved front teeth that help anchor the tongue and prevent water loss during each lick.
Behaviorally, mice alternate between licking and swallowing at intervals of 80–120 ms. Each lick delivers approximately 0.2 µL of water, resulting in an intake rate of 1–2 mL per hour when the animal is thirsty. The animal positions its head low to the water source, often using its whiskers to locate the surface before initiating the lick cycle.
Experimental observations using high‑speed videography show that the tongue tip contacts the water surface for roughly 10 ms before detaching. During this contact, the tip forms a thin film that spreads across the tongue surface, increasing the volume of liquid that can be drawn upward. After each lick, the mouse closes its mouth briefly to swallow, resetting the oral cavity for the next suction event.
Physiological controls involve hypothalamic osmoreceptors that detect dehydration and trigger increased lick frequency. Neurotransmitters such as vasopressin modulate the motivation to seek water, while peripheral receptors in the oral mucosa provide feedback on fluid volume, adjusting the lick rhythm accordingly.
In summary, mouse drinking relies on a rapid lick‑suction cycle driven by specialized tongue morphology, precise timing of mouth movements, and central regulation of thirst. The combined effect allows efficient acquisition of small water volumes from shallow sources.