Charlotte Francis finds that animals know how to have fun.

It's been all things animal in my world lately: the new wildlife documentary The White Planet with its frolicking polar bears; watching a blue tongue lizard amuse and confuse a cocker spaniel; and reading about the wonderfully modest Sir David Attenborough, who shrugs off his skill as a wildlife broadcaster extraordinaire by saying, "I've got birds of paradise on my side. All you have to do in my business is not stand in between them and the camera." So it seemed a natural segue for me to dip into Pleasurable Kingdom, Animals and the nature of feeling good by Dr Jonathan Balcombe, a research scientist based in Washington DC.

The premise of this highly accessible book is that pleasure plays an important part in how animals experience the world. In his foreword to the book, Peter Singer (co-author of The Ethics of the Food We Eat) points out that most studies in the animal movement have focused on suffering and neglected to look at animals' capacity for pleasure. Backed up with an impressive bibliography, Pleasurable Kingdom argues that while animal behaviour is influenced by evolution and survival, animals are not necessarily responding consciously to these influences. In other words, animals may experience pleasure for pleasure's sake.

In the absence of rigorous proof that pleasure is adaptive and that feeling good steers animals towards behaviours that promote survival, he presents a wealth of evidence and the book is divided into themes such as play, food, touch, sex, love and transcendent pleasures with a quote introducing each chapter. One of my favourites is from Joseph Wood Krutch: "Most robins seem terribly glad to be eating worms."

The author challenges the idea that humans are the chosen ones and cautions against comparing animal and human intelligence levels. A Wilson's warbler couldn't do a tax return, for example, but is a super navigator migrating thousands of miles each spring to return to a patch of woodland it nested in the year before. And for anyone who believes sheep are stupid, think again! Sheep can recognise 50 or more members of their flock from photographs of their faces. Even more impressive, sheep have been seen to solve the problem of an eight foot wide, hoof-proof cattle grid by rolling over it.

Some forms of sensory intelligence in the animal kingdom go beyond the human experience: the ability to see ultraviolet light, to hear at higher or lower frequencies and sensitivity to smells and tastes we cannot detect. The nose of the star-nosed mole is so well served with tiny nerves that 600 could fit on the head of a pin. Could such creatures be capable of greater pleasure than humans? Statistics also point to impressive social cohesion, and a lower "divorce" rate, in some animal societies - 90 per cent of bird species are believed to be monogamous and half mate for life.

There are similarities between man and beast too; all vertebrates share the same physical structure as humans and have five senses. MRI scans show animals experience similar emotions to ours and evidence suggests that animals with a backbone experience pain. Animals appear to dream, anticipate the future and plan ahead.

The author clearly has a close bond with animals and is the proud owner of pet rats, Rachel, Veronica and Lucy. In the chapter on food, he demonstrates that, given a chance, rats shun the fruit bowl and head for the donuts, or Balcombe's freshly baked peanut butter cookies. Rats also enjoy a good game of hide and seek and the sensation of being tickled.

The chapter on play and thrill seeking is particularly engaging. We are all familiar with the antics of cats and dogs, but perhaps less familiar with the idea of penguins, otters and bears tobogganing, dolphins surfing, elephants trunk-wrestling, ravens flying upside down, gorillas playing with labradors and red-neck wallabies playing tag with magpies. While play helps in the search for food and development of physical strength, it seems that animals also play for the heck of it. Animals playing in waves or water are often seen going back for another "go" and octopuses, turtles and reptiles climb up slides to repeat the pleasure of going down again. In similar vein, anecdotal evidence suggests that birds enjoy flight for the sake of it and also sing purely for pleasure.

Balcombe advises that the chapter on sex is not for the faint-hearted. He gives us a tour of the salacious shenanigans of the animal king - and queendom, explaining that much sexual activity takes place outside the breeding season, another example of animals seeking pleasure that is unrelated to survival. From spinner dolphins to swallows, quite a few animals seem to indulge in orgies but it is the apes and chimps that have the most colourful and, to put it politely, varied sex lives! In summary, animals are neither priggish nor especially shy

On top of sexual abandon, animals, it appears, are no strangers to alcohol and drugs. Birds such as waxwings and robins in North America gorge on fermented fruits, other birds "smoke bathe" on chimney tops and goats are credited with having discovered coffee. Abyssinian herders in the 10th century noticed their flocks becoming frisky after nibbling the red berries.

As any animal lover knows, animals have an enormous capacity for joy, love and loyalty. And it's not just dogs that become overjoyed when reunited with their owners. Merlin, an eight year old raven in the US, clung to his owner's shoulder all day after a six month absence. Many of us will know the famous story of Scottish dog Greyfriars Bobby, who visited his master's tomb every day for 14 years.

Parrots are fiercely loyal, too. American biologist Joanna Burger adopted a parrot, Tiko. After five years, Tiko demonstrated extreme jealousy when Joanna nursed an injured hen. But when Joanna was ill, Tiko laid out her hair strand by strand in a fan shape on the bed covers, rather like a mother brushing her daughter's hair. When Joanna recovered, Tiko performed a celebratory slide down the banister!

With tales of parrot love, pigeons differentiating the paintings of Monet from those of Picasso, chimpanzees marvelling at the sunset and fish enjoying their food, this book not only delights, but on a more serious note also raises ethical and moral questions about how we treat animals. Pleasurable Kingdom highlights our human responsibilities to animals as social beings with a wide range of emotions and feelings.

Pleasurable Kingdom, Animals and the nature of feeling good by Dr Jonathan Balcombe is published by Macmillan. RRP $29.95