Cats are Water Wizards
Water is essential to survival and land animals have evolved to meet their water needs in various ways. Some absorb water
through the skin, some extract water from the moisture in their food but most animals rely on drinking water to stay hydrated.
At first you might say, well of course animals drink water, but when you start to think about it, the simple act of drinking presents a challenge because fresh water is mostly a horizontal liquid surface in puddles, ponds, lakes and streams so animals must work against gravity to get the water up off the ground and into their mouths. This simple act of survival is actually a remarkable achievement.
It is physically impossible for a cat to suck.
Vertebrates (animals with backbones) use their tongue in two distinctly different ways. Vertebrates with complete cheeks, such as pigs, sheep, and horses, use suction to draw liquid upward and use their tongue to transport it into the mouth. However, vertebrates with incomplete cheeks, including most carnivores (cats are carnivores), are unable (after weaning) to seal their mouth cavity to create suction and therefore rely on their tongue to move water into the mouth. It is physically impossible for a cat to suck.