Animal Picassos at zoos abound these days, with many species sticking their paws, claws and more into non-toxic paint to create unique works of art. "Primates are among our most experienced painters," Heidi Hellmuth, curator of enrichment and training at the Smithsonian's National Zoo, told Discovery News. This golden lion tamarin, a small monkey native to Atlantic coastal forests of Brazil, would appear to prove the point.

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Painting is one of many activities that fall under what's known as animal enrichment, a program at zoos providing physically and mentally stimulating activities and environments. Christine McKnight, coordinator of animal enrichment and training at the Minnesota Zoo, told Discovery News that most species can paint in some way. "But some individuals take to it, while others don't," she said. Most primates, such as this golden-headed lion tamarin, are at least curious about the process.

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The list of animal artists at the Smithsonian's National Zoo includes some surprises, including this three-banded armadillo.

For some animals, such as the naked mole-rat, painting is an all body experience. Both Hellmuth and McKnight assured that every paint is non-toxic and water-based, with many products donated by supporters. The mole-rat's works have a Jackson Pollock look. "The animals enjoy the process more if it taps into a natural behavior and if they use a part of the body that mirrors a skill set from the wild," Hellmuth said.

Even hissing cockroaches and other insects can create works of art. From a professional standpoint, it may be difficult to value the skill, especially if the "artist" just runs across the canvas with paint-covered limbs. But McKnight said that "cockroach paintings can go for a high price. They are extremely popular."

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Potentially dangerous predators, such as Baruti the lion, show interest in painting too. McKnight said even grizzly bears at her zoo have created works of art. "They will put their full body in the paint and roll, rub and sit on the canvas," she explained.

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Animal artworks have led to a reliable source of income for zoos. Like true museum pieces, often copies are made of the originals, which may be stored. Paintings by rare animals, like Tian Tian the giant panda, can be quite valuable. "Painting provides great mental exercise," McKnight said. "If an animal doesn't want to participate, it's their choice. Among wolverines, for example, some want to paint while others don't."

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Human artists may invest tremendous energy and emotional effort into their works. The same appears to be true for certain non-human painters. Kojo the western lowland gorilla at the Smithsonian's National Zoo seems to put a lot of thought into his efforts. "The other day he looked creatively tapped out, taking a long time to just do 3-4 brush strokes," Hellmuth said.

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Enrichment activities at zoos and aquariums provide an integral part of an animal's care. This leopard gecko at the Minnesota Zoo seems to be enjoying the messy undertaking.

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Zoo animals have been painting for over a decade now, but the activity has grown in popularity over the past three to four years. More species at more zoos are getting involved. Red pandas Shama and Pili are just two. Art produced by many of the Smithsonian National Zoo's mammal and bird residents will be available for purchase at the National Capital chapter of the American Association of Zoo Keepers (AAZK) Art Show, which will take place during the spring of 2012.

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