For millennia, our ancestors have enjoyed, and even regarded as sacred, a variety of mind-altering substances. Cultural artifacts, visionary artwork and rituals in many indigenous cultures and past civilizations point to this fact. As Ethan Nadelmann remarked in a recent TED talk, “Our desire to alter our consciousness may be as fundamental as our desires for food, companionship, and sex.”

While Homo sapien consumption for consciousness-expanding purposes is well-documented throughout anthropology and history, ample evidence suggests we are not the only creatures who seek mind-altering plants and substances in their environment.

Indeed, plenty of our animal friends enjoy mind-altering substances: Some eat fermented fruits, psychoactive mushrooms, and opium poppies. Others rub themselves with crushed ants or angry millipedes.

The initial attraction to these substances might not be just to get high, but for nutritional or protective purposes. For example, fermenting fruits might be attractive to certain species because the process signifies the fruit is at its highest caloric value, and is also going to rot soon. In other cases, naturally occurring intoxicants might serve some curative function or contain nutrients that are otherwise scarce in the environment.

But, there’s compelling evidence to suggest that altering one’s state of mind for the simple purposes of experiencing that altered state is a natural drive common to many inhabitants of the animal kingdom. See for yourself.

1. Lemurs and capuchin monkeys get high off of millipedes.

The idea that some animals get high off other animals is an intriguing one, and lemurs and capuchin monkeys seem to be doing just this with poisonous millipedes. The millipedes store toxic chemicals, including cyanide, which they release in defense when provoked. The primates pick up and agitate millipedes and then rub them all over their bodies, coating themselves in the defensive secretions — here’s a BBC documentary clip on this. As mentioned in the video, the primary reason for this seem to be protection against a variety of parasites, but the monkeys and lemurs also seem to enjoy a thoroughly blissful intoxication as a result. The monkeys, being more social animals, have been seen passing a millipede around, reminiscent of a group of people passing around a joint.

2. Dolphins enjoy the psychoactive effects of poisonous pufferfish.

Similar to the lemurs and monkeys above, dolphins have been observed hanging out in groups of four to seven, passing around an angry pufferfish. The pufferfish releases an extremely potent poison called tetrodotoxin which is more deadly than nerve gas or the venom of the black widow spider, and thus is one of the most toxic compounds known to man. Evolutionary biologist Dr. Christie Wilcox is skeptical of the theory that dolphins are intentionally doing this for the purpose of intoxication and pleasure, but there is some compelling evidence to the contrary. For example, the BBC documentary Spy in the Pod showed dolphins passing around a pufferfish and then floating near the surface of the water, apparently in a “trance-like state.”

3. Many species of birds do what is called “anting.”

A seemingly odd behavior, ravens, myna birds, jays, magpies, and other birds sometimes either rub themselves with ants or get intimate with anthills to coat themselves in ants (see a jay do it here). This is called anting, and its purpose remains unclear.

An article published in the journal of the American Ornithologist’s Union in 1974 reviewed the possible explanations for anting. One theory is that the birds are coating themselves with the ant’s defensive chemical secretions, thus applying a protective coating much like when we apply insect repellent.

Another possibility is that the secretions serve to soothe the bird’s body during molting season. Others point to the curious movement sometimes observed during anting (described by one ecologist as “a curious dance that involved flopping around on the grass with its wings outstretched and its beak open”) as proof of an intoxicated state, suggesting that anting is pleasurable for the birds.

Perhaps the answer is a combination of these theories. Similar to how humans use cannabis, anting may at times serve a protective or curative purpose, while at other times be done mainly for the enjoyment of the altered state it brings about.

4. Many animals seek out fermented fruits in the wild.

It has been widely reported that elephants get themselves drunk from the marula tree’s fermented fruit. Anecdotal reports of these stumbling elephants go back over a century, and the phenomenon was portrayed in the film Animals are Beautiful People by James Uys (Uys also made The Gods Must Be Crazy). The idea is that the fallen fruit ferments either on the ground before being eaten, or in the elephant’s digestive system, yielding one drunk pachyderm.

As fun as it is to think about inebriated elephants, this theory has been debunked by an article published in the Physiological and Biochemical Zoology journal in 2006, and it’s been suggested that the clips shown in the above video were staged by artificially sedating the elephants. For starters, elephants don’t eat the rotten fruit from the ground, instead preferring to ram the tree trunk to shake loose the ripe fruit, even when there’s fruit on the ground available. Another hypothesis, which suggests that the fruit ferments in the digestive system, is also out of the question; the fruits are not in the digestive system long enough for that to happen, and the sugars needed for fermentation are metabolized by the elephant before they can be converted to alcohol by yeast. And, in order to get drunk an elephant would need to eat 1,400 fully fermented marula fruits — an unlikely feat. Despite its improbability, the myth, and convincing videos of seemingly drunk elephants, persist.

However, there have been confirmed reports of other animals that regularly consume fermented fruit. The pen-tailed treeshrew, native to Thailand and Malaysia, is known to regularly snack on the nectar of the bertam palm tree, sharing this indulgence with the slow loris and several other mammals native to that area, according to a study published in the Proceedings of the National Academy of Science in 2008. The palm’s flower bud houses a species of yeast that ferments the nectar, bringing it to a beer-like alcohol content of up to 3.8%. It is estimated that, in one night, the treeshrew can consume the equivalent of nine alcoholic beverages. However, they show no overt signs of intoxication because their bodies use more efficient ways of breaking down alcohol than we do, preventing the accumulation of alcohol necessary for getting drunk. Similarly, bats regularly encounter and consume fermented fruits in the wild. Like the treeshrew, they show no signs of intoxication. When scientists gave bats an alcohol solution and made them fly an obstacle course, they performed no worse than their sober counterparts.

Monkeys also have a taste for alcohol — not only do they seek out fermented fruits, but they also like to steal alcoholic drinks from tourists. And their taste for alcohol has allowed for some pretty interesting research on their drinking habits. Vervet monkeys that were given access to alcohol in a social setting show some striking parallels to the drinking patterns of humans. The monkeys could be grouped into social drinkers, which prefer sweetened drinks and only drink in the company of others; regular drinkers, which prefer their drinks straight, make good leaders, and are socially dominant; binge drinkers, which are aggressive and can drink themselves to death within months if given unrestricted access to alcohol; and abstainers. What’s more, not only the types of drinkers similar to humans, but the proportions of each of these behavior patterns in the monkeys studied reflects those found in human populations. These findings raise the possibility that our patterns of drug consumption are more fundamental aspects of our animal nature than we might think.

5. Horses seek out locoweed for its intoxicating effects.

Locoweed refers to any plant that produces the chemical swainsonine. It is thought that horses are initially attracted to these plants because they remain green longer than other plants once winter comes around. However, they begin to seek it out for its intoxicating effects, increasing their use over time. Farmers do their best to eliminate locoweed from their properties, as its frequent consumption is damaging to the animal’s health. A study published in the Journal of Animal Science in 2003 found that horses that ate the weed for two weeks developed significant weight loss and signs of depression. Swainsonine interferes with a metabolic enzyme, resulting in the buildup of the simple sugar mannose in neural cells. If severe, this buildup can lead to heart problems, reproductive difficulties, and neurological damage to the horses.

6. Jaguars eat the ayahuasca vine.

According to this Discovery article, humans aren’t the only ones that use Banisteriopsis caapi (one of the two plants used to make ayahuasca) as a psychoactive. This Amazonian jungle vine contains several compounds called beta-carbolines that potentiate the DMT in the ayahuasca brew by inhibiting bodily enzymes that would otherwise be responsible for breaking down the DMT. It turns out that jaguars also seek out the leaves of this jungle vine.

Higher doses of harmala alkaloids often result in vomiting and diarrhea characteristic of ayahuasca, so one possibility is that they consume the vine to purge the intestinal tract of possible parasites; a study of the Amazonian Piaroa tribe published in the Journal of Psychoactive Drugs suggests that eating the leaves grants the jaguar heightened sensory perception, helping them hunt. However, the jaguars are also known to roll around in ecstasy after consuming the vine, suggesting to some that its use is primarily for pleasure. See it for yourself here.

7. Reindeer eat the psychoactive Amanita muscaria mushrooms.

These red-and-white psychedelic mushrooms, native to temperate and boreal regions in the Northern Hemisphere and thought to be the sacrament referred to as Soma in one of Hinduism’s foundational texts, are also a favorite snack of reindeer. As Gordon Wasson relates in his book Soma: Divine Mushroom of Immortality, reindeer are reported to prance about after eating the fungi — which are commonly referred to as “fly agaric” — apparently reveling in their intoxicated state. Reindeer are also an integral part of the history of Amanita use by indigenous peoples of Northern Europe and Siberia. As Reset.me recently reported, a 2009 BBC video explains how the Sami people indigenous to the Arctic Circle have long used fly agaric mushrooms in their visionary rituals. It is theorized that the connection between reindeer, Sami and fly agaric mushrooms is the basis for the legend of Santa’s flying reindeer.

Not only did these people herd reindeer, the animal being their main source of food and clothing, but they also got high with a little help from their reindeer friends. The effects of Amanita muscaria are characterized by a certain unpredictability, as their ingestion can bring about a range of thoroughly unpleasant side-effects and physical symptoms. In time, it was discovered that muscimol, the active compound of the mushrooms, is not processed by the body but is instead flushed out through urination while the more toxic compounds responsible for the body load are broken down. This led to the practice in some places of drinking the psychoactive urine of the shaman who had eaten, and thus purified, the mushroom. Some shamans even drank the urine of reindeer that had eaten the mushrooms. It turns out that the reindeer, intelligent in their own right, also realized that they could get high from the urine of a human that had consumed the mushroom, leading to what Cracked humorously referred to as “The Circle of Piss.”

8. Wallabies ravage opium poppy fields.

Tasmania is a leading producer of opium poppies for the pharmaceutical industry, supplying the morphine necessary for the production of painkillers. There’s only one problem: wallabies love the poppies. They’ll raid a field, gorge themselves on poppies, and crush the plantations in the process. As reported by BBC in 2009, the issue of stoned wallabies was even discussed at a parliamentary hearing on the security of opium crops in Tasmania, with the country’s attorney general stating that wallabies were “entering poppy fields, getting high as a kite, and going around in circles.”

9. Pigs dig up truffles containing cannabinoids.

Black truffles, a gourmet delicacy for us humans, are also a sought-after snack for pigs. These mushrooms grow exclusively below ground and are identified by pigs by their aroma, said to be reminiscent of wet earth, dried fruit, and cacao. A recent article in the journal Phytochemistry revealed that the black truffle (Tuber melanosporum) contains the cannabinoid anandamide, a compound structurally related to THC that is also found endogenously in the human body and is a key component of the body’s endocannabinoid system. Anandamide derives its name from the Sanskrit word ananda, meaning “bliss.” Researchers suggest that the anandamide in black truffles might be “an ancient attractant to truffle eaters that are well-equipped with with endocannabinoid receptors,” indirectly suggesting that humans might be drawn to truffles for the same reason.