Animals That Sweat: How Horses, Hippos, Elephants, Camels, and Humans Stay Cool
September 24, 2026
Most mammals never break a sweat, no matter how brutal the afternoon sun gets. The short list of animals that sweat relies on this liquid cooling trick in wildly different ways, and the mechanisms behind it are stranger than a simple bead of perspiration.
Horses lather up like a bar of soap left in the bath too long. Hippos secrete a substance that looks like blood but works like sunscreen. Elephants, despite their reputation for heat tolerance, barely sweat at all in the way most people assume. Camels can go most of the day without producing a drop, and humans remain the undisputed sweating champions of the animal kingdom.
Understanding why these five animals cool down so differently reveals a lot about how evolution solves the same problem in completely different ways. Below is a closer look at each one, along with the science behind their unique approach to staying cool.
| Animal | Sweat Gland Type | Primary Cooling Method | Standout Trait |
|---|---|---|---|
| Horses | Apocrine glands | Evaporative sweating | Foamy sweat containing latherin |
| Hippos | Modified skin glands | Water immersion + secretion | Red-orange antibiotic pigment |
| Elephants | Toe-area pores only | Ear flapping, mud, skin permeability | No true body sweat glands |
| Camels | Eccrine glands | Delayed sweating, heterothermy | Body temperature swings by 6°C |
| Humans | Eccrine glands | Continuous evaporative sweating | Densest sweat gland coverage of any mammal |
1. Horses: Nature’s Champion Sweaters
The horse (Equus caballus) belongs to an exclusive club. Aside from higher primates such as monkeys, apes, and humans, horses are among the only other animals in the world that perspire profusely, making them one of the few that could challenge humans in a marathon. That endurance advantage comes from apocrine sweat glands spread across the neck, chest, and flanks.
What makes horse sweat unusual is not just the volume but the chemistry. Horses have apocrine sweat glands, but their secretion contains the protein latherin, which is a natural detergent thought to help water distribute over the fur to speed evaporation. Anyone who has watched a horse finish a hard gallop has seen the result: thick white foam collecting around the thighs and neck.
This lather forms most where rubbing takes place, and it looks remarkably similar to the suds produced when washing clothes or dishes. The reason horses need this extra help is their coat. Their thick, waterproof hair prevents rapid evaporation of sweat, which would otherwise fail to produce a cooling effect on its own.
Key Insight: Latherin doesn’t just make horse sweat foamy for show. By breaking the surface tension of water on waterproof hair, it lets moisture spread across more surface area, so more heat escapes through evaporation during hard exercise.
The payoff for all that sweating is real. Horses sweat mainly through their bellies and necks, and anyone who has spent enough time working with horses knows they sweat heavily while exerting themselves. This capacity for sustained evaporative cooling is a major reason horses can be worked or ridden for hours in warm climates without overheating, a trait explored further in the detailed breakdown from ScienceABC.
2. Hippos: The Mystery of Red Sweat
The hippopotamus (Hippopotamus amphibius) produces one of the strangest bodily fluids in the animal kingdom. Hippos emit a blood-like substance that looks like sweat, which has fueled decades of folklore about hippos sweating blood. The reality is more interesting than the myth.
Cambridge hippo biologist Keith Eltringham points out a technical wrinkle. The secretions are not technically sweat because hippos don’t have the small sebaceous glands that produce it; instead, bigger, deeper glands release liquid through skin holes visible to the naked eye. He is also skeptical the secretion does much cooling work on its own, since a hot hippo typically just lumbers into the nearest water to cool off.
So what is the secretion actually for? Within a few minutes of perspiration, the colorless, viscous sweat of the hippopotamus gradually turns red, then brown as the pigment polymerizes. Researchers who isolated these compounds found something remarkable: the unstable red and orange pigments are non-benzenoid aromatic compounds that are unexpectedly acidic and have antibiotic as well as sunscreen activity.
That dual function explains a lot about hippo behavior. Since males frequently gash each other during territorial fights, the antibacterial properties likely help keep those wounds from becoming infected. Each pigment’s light absorption peaks in the ultraviolet range, prompting photobiologist Gavin Greenoak to note there’s no question the hippo is getting its own built-in sunscreen. Hippos also tend to be among the animals that sleep a lot during the hottest hours, submerging for much of the day and becoming active mainly at dusk. For more animals sharing that first letter, see this list of animals that start with H.
3. Elephants: The Surprising Non-Sweaters
Given their size and their reputation for baking under the African sun, most people assume elephants sweat buckets. They don’t. Unlike most mammals, elephants cannot sweat to cool down in the way people typically imagine. The reason lies in their anatomy.
Most mammals sweat through glands connected to pores, but elephants have pores only between their toes. That single fact rewrites the entire cooling strategy for the world’s largest land animal. Instead of relying on sweat glands across the body, elephants lean on a combination of ears, skin, and mud.
Important Note: Elephants are frequently listed among “animals that sweat,” but the science says otherwise for most of their body. Their skin does become more permeable in heat, allowing some moisture loss, yet this differs fundamentally from the dedicated sweat-gland cooling seen in horses or humans.
Research published in the Journal of Experimental Biology adds nuance to the picture. Scientists measured heat and moisture released by 13 African and Asian elephants and found their skin becomes more permeable at air temperatures as low as 10°C to 12°C, allowing them to perspire through the skin surface itself rather than through glands. This permeability lets elephants lose more moisture through evaporation, though it also means they need to drink a lot of water to avoid dehydrating, up to 200 liters per day at the height of summer.
Ears do most of the remaining work. When elephants get too hot, they flood their ears with blood to dissipate body heat, and can also fan their ears to increase airflow over the skin. The African bush elephant (Loxodonta africana) adds another trick entirely: a landscape of tiny surface cracks across the skin, especially on the face and trunk, that act like miniature reservoirs channeling and holding water and mud long after a bath.
Mud wallowing rounds out the toolkit. Wallowing in mud or dust is another form of thermoregulation elephants use, since a layer of moisture, mud, or dust traps cooler air close to the skin and also blocks excessive sun exposure like sunblock. Elephants rank among the animals that get by on very little sleep, often resting only a couple of hours a night, which leaves plenty of daylight for these cooling rituals. Learn more about the science of elephant thermoregulation from the AAAS Science journal and the Kariega Game Reserve field guide.
4. Camels: Masters of Water Conservation
The dromedary camel (Camelus dromedarius) takes the opposite approach from a horse. Rather than sweating freely, it delays sweating as long as possible. Camels rarely sweat, and their body temperature fluctuates, rising during the day with the environmental heat and falling again at night when it cools down.
This strategy, called adaptive heterothermy, is one of the most efficient water-saving tricks in the animal kingdom. Camels fluctuate their body temperature between 34°C and 42°C, which minimizes perspiration and avoids water losses through evaporation. Rather than sweating to hold a constant internal temperature the way humans do, a camel simply lets its body run hot for a while.
The numbers behind this trick are striking. Throughout the day a camel’s temperature rises from muscular work, solar radiation, or both, but it does not begin thermoregulating by sweating until its rectal temperature reaches 40°C, allowing it to absorb heat across a 6°C range compared with only 2°C in humans. By tolerating that swing, a camel may save around 5 liters of sweat in a single day.
Pro Tip: Camels aren’t immune to dehydration, they’re just efficient. When water does become scarce, they can still drink enormous amounts fast to recover, so access to water remains essential even for an animal built to conserve it.
That recovery capacity is genuinely dramatic. Dromedaries are capable of drinking huge amounts of water, reaching up to 200 liters at one sitting to compensate for fluid loss. Their cells also handle heat stress far better than human cells do. Camel platelets show relatively higher resistance to temperatures of 43–45°C compared with human platelets, and even extreme temperatures of 50°C aren’t enough to disrupt camel platelet function while causing damage to human platelets. Camels share this heat-tolerant physiology with close relatives detailed at the Natural History Museum, and the full cellular story is covered in research summarized on the National Center for Biotechnology Information.
5. Humans: The Sweatiest Mammals on Earth
Modern humans (Homo sapiens) may not be the biggest or the toughest animal on this list, but they win the sweating contest outright. Humans and other primates rely on sweating as their primary cooling method, alongside horses, whereas cattle and camels only sweat to a lesser extent.
This isn’t a minor advantage. Humans sweat far more than most other animals when compared pound for pound. That capacity comes down to sheer gland density and distribution across nearly the entire body surface, rather than being concentrated in a few regions the way it is in horses or hippos.
The type of sweat matters too. Human sweat glands work differently from those in other mammals that do produce moisture. Humans have sweat glands that secrete water onto the surface of the skin, while horses have a different type of gland common in running animals, according to researcher Yana Kamberov. This eccrine-dominant system is one reason humans can sustain endurance activity in heat far longer than most other primates.
Sweating this efficiently comes at a cost worth remembering. Losing too much fluid through perspiration without replacing it can quickly become dangerous, a concern that applies to every animal on this list, not just people. If sweat-based cooling breaks down entirely, dehydration and heat-related illness can follow quickly, which is why staying hydrated during hot weather activity matters as much for wildlife caretakers as it does for athletes. For a full rundown of every animal known to produce true sweat, the original list of animals that sweat is a useful companion read, and the Smithsonian’s roundup of unusual cooling strategies covers several species that skip sweating altogether.
Comparing these five animals shows there is no single “correct” way to beat the heat. Horses and humans lean almost entirely on sweat glands. Hippos produce something that looks like sweat but functions more like medicine and sunscreen. Elephants and camels prove that skipping sweat, or delaying it as long as possible, can be just as effective when paired with the right anatomy and behavior. Whichever strategy a species evolved, the goal is identical: keep the body’s internal temperature steady enough to survive whatever the day throws at it.