Short answers, pulled from the story.
The swallowing process is completed by peristalsis which delivers the liquid through the esophagus to the stomach. Much of this activity relies on gravity to assist the movement while infants employ suction where lips press tight around a source.
Cats lap up water with their tongues in a spoon-like shape that pulls a column of liquid into their mouths. Elephants draw water into their trunks and squirt it directly into their mouths.
A decline in total body water leads to dehydration and eventually death by hypernatremia. An overconsumption of water can lead to water intoxication which dangerously dilutes the concentration of salts in the body.
The USDA recommends a daily intake of 3.7 liters for an adult male. Adult females require 2.7 liters per day according to federal guidelines.
Evidence of fermented drinks goes back as early as the Neolithic Period. The first pictorial evidence appears in Egypt around 4,000 BC.