A BUG'S LIFE

A MAN once told me that falcons nest in the rooftops of the Manhattan skyscrapers and swoop to feed on the sparrows huddled against the facades of the smart hotels lining Central Park. The man was intrigued and troubled. At first he saw the falcons as a metaphor for the existing hierarchy in contemporary America, then as a wild, exhilarating vindication of the natural world - a contrast to vulgar human predators. Then he decided that their presence represented nature becoming unnatural; the falcons did not belong on these manmade crags.

Catherine Chalmers also lives in Manhattan and is interested in natural predators, but, unlike the falcon-watcher, she is an artist, and ambiguity, for her, is enriching rather than confusing. She works with a camera, mainly photographing insects, and has produced a series of pictures she calls "Food Chain". A bright red tomato is pulped by a caterpillar, which is chewed by a praying mantis, which is swallowed by a frog. Everything feeds on everything else, but we knew that anyway, so what's the big deal?

The difference lies in the vivid beauty of these weird, compelling pictures. The sharp, luscious colours erupt on to a stark, white background, traditionally used in fashion shots rather than nature photography. Nor, when you think about it, is this food chain natural. It's a staged drama. Even the tone of the insects' guts has been preconceived. "When the mantis bit into the caterpillar it was like a paint tube being squeezed," says Chalmers, who discovered she could obtain different colour effects by changing the caterpillars' diet.

Some of the pictures are funny and some are shocking. She has made studies of tarantulas feeding, of mice being born and of the time when she presented a "pinky" - a newborn mouse - to her snake, Pumpkin, who constricted and swallowed the tiny pink form. The picture of the orange-coloured corn- snake brooding over the helpless baby mouse made me shiver.

Chalmer's pictures do not promote themselves as intellectual art. Instead, they provoke an emotional response, making you wonder which side you're on. "That's an important part of it," she says, "watching how your sympathies change. First the caterpillars look pretty, then the praying mantis, well it's got eyes and a head, so it's more like what we consider to be human. Then the frog looks kind of cute. The pinky was harder, because we're mammals too. At one point you feel really bad about it, then you're happy the snake ate and think, well, the mouse was going to die anyway." She thinks. "I never cared that much for the caterpillars, because they bit me. But the praying mantis have red insides to their mouths, as if they wear lipstick. And they're smart."

Chalmers lives in a Soho loft with her dog Leo, a chauchau. Now 40, she is frank and funny and, when talking about her pictures, alternates between the tones of a teenager describing a parent's peculiar occupation, and those of a parent wondering at a strange enthusiasm of its child's. Born in San Francisco, she studied engineering and designed toys before going to art school, ending up at the RCA in London. She was never comfortable with paint. "You have to have a relationship with the medium," she says. "I was always looking for ways to get the subject more on the canvas." She came to New York in 1985. "It was scary," she recalls. "Lots of weird people. I didn't know anybody." For a few years she experimented with different materials, including dead insects. It was partly because she knew nothing about photography that she was attracted to it: "It was a transparent medium; a way of getting closer to the subject matter."

In the early Nineties she was photo- graphing swarms of houseflies when she had her epiphany. "I looked through the lens and the world changed," she recalls. "Instead of seeing patterns of flies I saw them greeting each other and hanging out and having sex, eating and dying." Flies devote their lives to breeding and many of her photographs of houseflies - huge, grey, translucent creatures - are fly- porn. They aren't beautiful but, seen on this scale, a fly masturbating is less repulsive than I would have expected.

Chalmers has watched a lot of sex and violence, and has seen many happy couples fall to eating each other. She describes how she once watched a female praying mantis eat a male. When he tried to get off her, "she reached around and grabbed him and bit his face off. And, she did it, I guess, because when she bites his head off, he continues to give her sperm. Apparently his head acts as an inhibitor ... He's very cautious around her and his caution seems to originate in his head. If she bites it off, she gets more sperm."

The work is painstaking. She sometimes stays up for days on end to get the right shot. She can stage-manage the proceedings only so far. "The situation you've created can be reversed," she says. "A fully grown mantis might turn on the spider."

Because she breeds most of her own insects, her loft is scattered with glass cases full of small, busy lives. These, combined with her plants and the shady lighting, give the apartment a feeling of seclusion and intensity - a microcosm inside the urban jungle. It's a concentrated atmosphere in which Chalmers can explore her unnatural relationship with the natural world. "For hundreds of years," she says, "the majority of the population worked in agriculture and saw every day around them all these processes of life and death." She thinks that we now have confused ideas about what kind of death is acceptable. Human violence is ubiquitous and graphic, but we are squeamish about the processes by which our food is produced, and find it shocking that some animals eat their young. Sometimes we want to impose our ethical system on the natural world; at other times we appeal to its savagery to justify our own behaviour.

Another series of Chalmers' pictures deals more overtly with the question of what constitutes "nature", although the photographs in question often seem more funny than philosophical. They involve cockroaches, her least favourite insects. She rears the roaches, then chills them in a fridge until they are supine enough to hold, and hand-paints them to create cheerfully coloured new species. In the pictures, the bright yellow and black bugs nestle inside the bells of summer flowers. They are pretty nature shots in the style of National Geographic - until one notices the telltale antennae and creepy brown feet. "I call the black and yellow roaches lady-beetles," she says, smiling happily, "and the others yellow orchid bugs. Nice name."

The roaches remain still only for a minute, so it takes five chillings to produce a hand-painted lady-beetle. The most arresting pictures are those in which Chalmers filled a roach-scale house with the pests and then took candid shots of the roach family at home. Vast antennae wave above a fridge; glimpsed through a window, a cockroach as big as a coffee table scuttles across the lounge. At a window, a roach peers out from behind lace curtains at the gathering night, as if waiting for its roach love to return home.

Chalmers might be saying that humans are roaches, or that we have much in common with the species we like least. But her starting point seems to be humour and compassion rather than ideas - and that sets her aside from the pig-in-blue formaldehyde school of conceptual artists. There's a visible battle in her work between revulsion and curiosity, but she emerges as an artist more interested in the processes of life than of decay. "People are always saying we have to go back to the natural way of living," she observes. "So when was that? When the Native Americans lived, they depleted the buffalo herds. England used to be covered in trees. Everywhere, at all times, man has altered his environment."

It's cheering to think that our mistakes might inspire us. Perhaps that's the message of Chalmers' tarted-up roaches with their horrible creepy antennae, or her slick, sly food chain: that we have the power to control our environment, to decide what is or is not natural, and to see the potential for beauty in what we dismiss as ugly.