Danger-junkie orangutans in Borneo climb dead trees and destabilize them until they begin to fall. They scream with excitement as they cling...

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Danger-junkie orangutans in Borneo climb dead trees and destabilize them until they begin to fall. They scream with excitement as they cling to the falling tree. Just before the tree hits the ground the orangs leap to another tree or vine, narrowly escaping death. Researchers call this peculiar behavior snag-riding and liken it to bungee jumping for monkeys. While no one can ask orangutans if they enjoy the same adrenaline rush as a person playing an extreme sport, one animal behaviorist sees this monkey fun as a bit of harmless thrill-seeking.

A growing number of scientists agree that animals are conscious and capable of experiencing basic emotions, such as happiness, sadness, boredom or depression. A few scientists even see the possibility for higher animal emotions like love, jealousy and spite.

Scientific literature, dating back to Charles Darwin, is dotted with examples of animals loving life, but rarely does the scientific community allow such musings. In fact, only one scientist is looking at the eat-or-be-eaten animal kingdom as a place where fun and mischief define the in-the-moment lifestyle of most animals.

Five years ago behaviorist and animal-rights activist Dr. Jonathan Balcombe stood on a Virginia hotel balcony watching two crows intimately groom each other in the comfort of an abandoned billboard. He felt that the birds liked what they were doing, even if engaged in a natural, beneficial act, such as picking parasites off the other’s feathers. That moment changed the way he would view animals forever.

“I watched the crows enraptured and had an epiphany,” Balcombe says. “I thought, ‘Aha! Pleasure,’ then started recording observations through pleasure contexts.” That led to a book, “Pleasurable Kingdom: Animals and the Nature of Feeling Good” (MacMillan, 2006; $24.95), which is filled with hundreds of examples of animals living it up, thanks to developed senses of touch, taste, sight, sound and smell.

Balcombe recounts a favorite example of Kenyan hippos receiving the hippopotamus equivalent of a high-end spa treatment in a freshwater spring. They splay their toes, open their mouths wide and wait for a school of cleaner fish to remove parasites and slough off dead skin, he recalls. Balcombe knows that the hippos and the fish both benefit from this arrangement. “My interpretation is that it is also enjoyable for them,” he says.

The first to admit his premise is hardly unique, Balcombe thinks his work merits a broader look. “Science has neglected this issue,” he said. Identifying positive affect has been a part of animal-behavior studies since the 1930s, when Donald Griffin, the noted biologist who discovered that some bats use echolocation to see in the dark, founded the field of animal thinking called cognitive ethology. Balcombe, who believes nature rewards behaviors that promote evolution, wants to take it a step further.

He illustrates his point by looking at why humans spice food. There may be an evolutionary reason beyond tantalizing our taste buds.

“Evidence currently supports the hypothesis that the antibacterial properties of spices account for our culinary habits,” Balcombe says. “Yet, when you reach for a burrito, are you thinking about banishing bacteria?” he asks. “No, you are enhancing the palatability of your food.”


Some scientists do not share Balcombe’s vision of a freewheeling, happy-go-lucky animal kingdom.

“I know of no anecdotal evidence of higher emotions in animals below great apes,” says University of Washington associate professor Jim Ha.

He admits that there is little scientific study on higher emotions in animals because it is difficult to measure and harder to fund. “It’s as elusive as measuring dreams in animals,” says the primate-, killer-whale- and crow-researcher. Ha wonders how Balcombe can presume to know what animals enjoy.

Ha concedes that “to a degree” scientists can see animal brains respond the same way human brains respond in similar situations. But high-resolution brain scans only capture simple, physiological emotions that involve the release of specific brain chemicals. Without brain scans, most field researchers rely on observed behavior and sometimes that can be misleading.

People smile when they are happy, but chimpanzees grin when they are anxious or under stress. So human interpretation of how animals respond in pleasurable situations is becoming the subject of much debate.

“We know that what makes a dog happy won’t necessarily work for a cat,” says Thea Brabb, attending veterinarian for the University of Washington.

Most of the time, bona fide scientific research omits interpretations of what the observer thinks the animal is feeling. That is called anthropomorphism and is usually taboo because it requires projecting human emotions onto an animal without really understanding the true nature of the behavior. It’s just a guess based on what is already known. Scientists steer clear of this practice, unless it promotes science.

Dr. Jaak Panksepp, a researcher at Washington State University, studies the positive feelings of rats. Recently, he discovered that rats “enjoy” being tickled.

Panksepp measured ultrasonic squeals associated with tickling and petting. He found the rats squealed seven times more while being tickled. Though well beyond the range of human hearing, he noted that other rats reacted positively to the high-pitched sounds. He also discovered that they learned to recognize when they were about to be tickled and ran across the cage faster in anticipation.

Let’s talk about sex

Some pleasure-seeking — especially involving nonprocreative sex — will undoubtedly shock some zoo patrons. Balcombe takes examples from a Seattle biologist’s book to build his argument that sex is pleasurable. Biologist and author Bruce Bagemihl surveyed the Zoological Record (1978-1997), which contains more than a million documents from more than 6,000 scientific journals. His book, “Biological Exuberance: Animal Homosexuality and Natural Diversity,” was published in 1999 and started the discussion about sexuality in the animal kingdom.

“To peruse Bagemihl’s masterpiece is to meet evidence of pleasure-generating sexual behavior on practically every page,” Balcombe says.

If animals have sex only to propagate their species, they would not spend time or waste energy on sexual activity when there is no hope of producing viable offspring. Yet they do.

“Many animals routinely copulate or engage in sexual activities outside of the breeding season,” Balcombe says. “Most biologists today also recognize same-sex sexual interactions as being part of the normal, routine behavioral repertoire of the animals that engage in them.”

Dolphins engage in several forms of recreational sex. Bonobos engage in open-mouthed kissing. Male giraffes mount each other. Mountain goats, wildebeest, rhesus macaques and proboscis monkeys devote a significant proportion of their sexual behavior to nonprocreative sex.

But, much of the sexual activity among animals does lead to the next generation. Oxytocin, a hormone associated with human social bonding, is just as important in giving mother animals the inclination to care for their babies.

“Nature is replete with signs of parental love,” Balcombe says, offering examples. Orca mothers watch as their calves explore and play. Chimpanzee infants cradle and groom logs as part of the transference of their mothers’ love.

Researcher Ha takes issue with Balcombe’s high concept of animal love. He doesn’t deny that many animals, including, dogs, cats, primates and even crows have simple, physiologically triggered responses. But higher emotions, such as grief, love, jealousy, envy and spite come from a different part of the brain and require more than just a burst of brain chemicals. They require a neocortex, a key part of the brain used for higher cognition, which animals have in varying degrees. “With brain chemistry and data, differences between physiological and higher emotions are evident,” Ha says.

But attitudes are changing, says Dr. Al Kamil, chair of the biology department and a bird-researcher at the University of Nebraska. Within the past few years, the concept of intelligent birds is becoming acceptable.

“[My] work has been cited more in the last three years than in the previous 25,” Kamil says. “So, attitudes are changing.”

Balcombe insists the most persuasive argument for pleasure in animals is that it is adaptive.

“Pleasure is nature’s way of rewarding good behavior,” he says. This also helps to reinforce that same behavior the next time it is performed.

Michael Bradbury is a Seattle-based freelance science writer: mikeb@seanet.com