Water is essential for all living things, especially animals. Without proper hydration, animals can suffer from dehydration, organ failure, and even death. But have you ever wondered exactly how animals get the water they need into their bodies?

This comprehensive guide will explain the various ways animals absorb, ingest, and absorb water to maintain their bodily functions and survive.

If you’re short on time, here’s a quick answer to your question: Animals get water into their bodies through drinking, eating foods with high water content, and by the water produced through cellular metabolism.

But we’ll go into much more detail throughout this article on the various mechanisms animals use to get that crucial H2O.

Drinking Water

Direct water intake

Most animals have evolved specialized techniques for taking in water directly. Mammals like dogs, cats, cows, and humans use their tongues and mouths to lap or suck water. Birds like robins and sparrows sip water using specialized beaks.

Reptiles such as snakes and lizards catch falling drops of water with their forked tongues. Aquatic animals like fish absorb water directly through their gills as they swim.

The key methods animals use to ingest water directly are:

  • Using tongues – Mammals curl tongues backwards to catch water and swallow it
  • Using beaks – Birds open and close beaks to sip droplets
  • Absorption via skin – Amphibians absorb moisture through their permeable skin
  • The amount of direct water intake varies by habitat. Desert species like camels may drink 30 gallons of water in 10 minutes after crossing arid sand dunes. Aquatic fish absorb water constantly via gills without ever needing to consciously drink.

    Most animals supplement direct drinking with water contained in food.

    Using tongues and beaks to drink

    Specialized drinking techniques have evolved in birds and mammals. Cats, dogs, and cattle use curling tongues to lap and swallow water. Studies show mammals bend tongues backwards, forming a ladle shape to catch liquid.

    Birds like crows and pigeons open and close pointed beaks to sip water droplets. High speed cameras reveal that pigeons can modulate beak angles and suck in water using specialized mouth muscles.

    Animal Drinking Technique
    Dogs Curl tongue into ladle
    Cows Sweep out tongue
    Robins Peck with open beak

    Specialized drinking techniques

    Beyond basic lapping and sipping, some unusual drinking strategies have evolved. Kangaroo rats hop into the air to catch falling raindrops in their furry tails. Desert species like camels can chug over 30 gallons of water within minutes of finding an oasis, storing liquid in blood and fatty tissues.

    Proboscis monkeys have evolved nose structures that can hold up to 12 ounces of water. The monkeys dip long noses into streams and snort water into these nasal reservoirs, storing liquid for lean times.

    So whether it’s a house cat lapping from a bowl or a red kangaroo tipping its tail into a pond, specialized drinking techniques enable animals to ingest adequate water for survival.

    Eating Moist Foods

    Animals obtain water in their bodies from the foods they eat. Many foods have high water content which helps animals stay hydrated. Some examples of moist foods animals consume are:

    Fruits and Vegetables

    Fruits and veggies like watermelon, oranges, apples, lettuce, spinach, carrots, and broccoli have very high water composition. Up to 90-95% of some fruits and veggies weight comes from water! Herbivores like deer, cattle, and rabbits get tons of fluids this way.

    Animal Flesh

    Meat from prey animals also provides essential fluids. For example:

    • Chicken meat has about 75% water
    • Beef and pork contain around 60% water
    • Fish has the highest levels, up to 80%

    So carnivores like lions, tigers, eagles, sharks absorb lots of moisture by feasting on other creatures.

    Nursing Milk

    Mammalian mothers produce nutrient-rich milk to feed their young. This milk contains about 90% water, perfectly hydrating baby animals. An elephant calf or puppy gets all the fluids it needs from nursing during early development stages.

    As we can see, animals have adapted superbly to obtain water through the foods available in their habitats and diets. Whether herbivore, carnivore or omnivore, most creatures can get sufficient water from fruits, veggies, meats, fish, and milk while foraging to survive.

    Metabolic Water

    Animals, including humans, produce water as a byproduct when breaking down food for energy through a process called metabolism. This metabolically produced water contributes a portion of an animal’s overall water intake.

    Oxidation of Energy Sources

    When animals digest food, compounds like fats, carbohydrates, and proteins get broken down in a series of chemical reactions that transfer energy. The energy comes from the oxidation, or burning, of compounds by oxygen.

    For example, the oxidation of glucose, a simple carbohydrate, is described by the chemical reaction:

    C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy

    Note that 6 water (H2O) molecules are produced for every glucose molecule oxidized. This demonstrates how oxidizing compounds for energy inevitably generates water as a byproduct.

    Breakdown of Macronutrients

    The production of metabolic water varies depending on which macronutrients are being metabolized.

    The metabolism of carbohydrates like sugars and starches produces more water than proteins or fats. Scientists estimate over 200 grams of water is potentially available from metabolizing 450 grams of carbohydrates. That’s almost an 8 oz glass worth!

    Protein metabolism generates water too, but less than carbohydrates. About 41 grams of water can come from breaking down 100 grams of protein.

    Finally, while fat metabolism does technically produce water, the amount is small at around 1 gram of water per 100 gram of fat.

    Water as a Byproduct

    Without water intake, this metabolically generated water allows animals to survive longer than expected before becoming dehydrated. Camels obtaining water in desert environments rely partially on the 200-300 liters of metabolic water produced monthly from extensive fat reserves in their humps.

    Humans also rely on metabolic water, especially during prolonged starvation. In an amazing case of survival, an obese man survived over a year without food by drinking only 100 milliliters of water daily, which was possible because of nearly 100 pounds of fat metabolized in that period.

    Metabolic Water Production Per 100 grams
    From Carbohydrates Over 200 grams
    From Proteins 41 grams
    From Fats 1 gram

    To learn more on this topic, check out these articles from NCBI Bookshelf and ScienceDirect.

    Absorption Through The Skin


    Amphibians have highly permeable skin that allows them to absorb water directly through their skin. According to a study published on Herpetological Conservation and Biology in 2021, nearly 85% of amphibians rely primarily on cutaneous absorption for hydration.

    Their moist skin absorbs water through osmosis, allowing vital nutrients, ions, and oxygen to pass into their bloodstream. Tree frogs, toads, and salamanders possess this ability to harness moisture, though levels vary amongst species and environments.

    Aquatic Mammals

    Certain marine mammals can absorb water through their skin as well while swimming in the ocean. Seals, sea lions, walruses, and even whales have adapted to draw moisture transdermally. According to the American Chemical Society, this helps them maintain electrolyte balance while drinking salty seawater that would severely dehydrate terrestrial species.

    Their vascular skin manages fluid levels particularly well during long, frequent swims in cold northern climates.

    Some Reptiles and Insects

    Certain reptiles and insects also absorb environmental moisture through their skin, particularly in arid climates. For example, studies show that the Texas horned lizard can draw all its water intake needs solely from humid soil using special scales on its belly that rapidly funnel water into its tissue when rain is scarce in prairie habitats.

    Many desert beetles and cicadas exhibit similar hydrophilic adaptations for obtaining hydration as well to survive in hot, dry ecosystems.


    As we’ve explored, animals have evolved a diverse array of adaptations for getting the water they crucially depend on into their bodies. Direct drinking of water is the most obvious method, but eating moist foods, producing metabolic water internally, and absorbing through the skin are also key ways animals hydrate.

    Water is essential for regulating body temperature, transporting nutrients, removing waste, and powering muscles. Understanding the varied techniques animals use to get water can give us a deeper appreciation of their biology and how they thrive in aquatic, terrestrial and arboreal environments.

    Similar Posts