The word organic means different things to different people. To the gardener it means compost heaps. To the chemist it means carbon compounds. To the artist Fabian Pena, it means American cockroaches, those chunky nocturnal charmers often seen skittering around drainpipes or on the street. “;I have collected cockroaches from many different places,”; Pena said. “;From Cuba, Mexico, Miami, Houston, everywhere I travel.”;

He kills the cockroaches with a spray, pops them into a jar, takes them back to his studio in Florida, and then puts their parts to work in his art. He glues their legs together into long, lacy cylinders that look like giant larval casings. He arranges their wings into medically precise images of a human skull, foot bones and hand bones, all scaled to his own head and appendages.

Pena likes the medium of cockroach aesthetically, the way he can use the different tones in the wings as his palette to convey light and shadow. He likes it metaphorically, how we are disgusted by something with which we have so much in common—the same taste in foods, the same easy adaptability to every possible niche. “;Cockroaches are a witness to our daily lives,”; Pena said. He also likes his medium pragmatically. “;It's a material that I can easily find,”; he said, “;and it's cheaper than buying paint.”;

Pena is among the growing ranks of artists who have gone natural, who are scavenging the world's vivarium and rummaging through the life sciences in search of materials, ideas, cosmic verities, tragicomic homilies, personal agency, a personal agent, a way to stand out in the crowd.

Laura Splan, a Brooklyn-based artist and certified phlebotomist, decorates wallpaper with her own blood. On first seeing the wallpaper, viewers have “;a pleasant visual engagement”; with it, Splan said. But after learning of the main ingredient from an accompanying card, she said, a “;more complicated”; reaction unfolds, a blend of ick and fascination, rearing back and coming closer, and mutterings of “;I sure hope she doesn't have any blood-borne diseases.”; With similar transfiguring glee, Levi van Veluw of the Netherlands treats the flesh of his face and torso as topsoil, slathering on layers of moss, grasses, leaves and florets until he looks like a kind of Julius Caesar Chia Pet.

Many examples of mulchy, redolent, unmistakably organic art are on display in a new exhibit called “;Dead or Alive,”; at the Museum of Arts and Design in New York. The museum recently hosted a round-table luncheon in which scientists and artists addressed the hardy evergreen issue of how much the arts and sciences had in common and where they differed. The basic conclusion: both enterprises are important, difficult, creative, driven by insatiable curiosity and a desire to solve problems, but artists are allowed to make stuff up and scientists really shouldn't.

Whatever the symposialchin rubbings, some practitioners of the new crossover art have serious scientific credentials and are not afraid to use them.

Lizzie Burns is a biochemist and artist affiliated with Oxford University who designs jewelry and men's ties based on the chemical structure of celebrity molecules like testosterone or dopamine. “;The designs of chemical structures can have an intrinsic natural beauty and balance,”; she said. Not to mention a certain conceptual consistency: there's caffeine with its three reactive “;hands,”; as she calls the little methyl groups, waving at you to wake up; the lightning-bolt zigzag of the capsaicin molecule that gives chili its fire; and the bicycle shape of Ritalin, inviting the aimless wanderer to hop aboard and ride.

Other artists have little formal scientific training but are avid autodidacts or will collaborate with scientists if it helps them hone their point. Christy Rupp worked with the paleontology department at the American Museum of Natural History to construct accurate, life-sized model skeletons of a dodo, a great auk and other birds that humans have driven to extinction. The skeletons are elegant, and beautiful to behold, and they are made of discarded chicken bones from fast food restaurants like KFC. Rupp's message: throw-away food, thrown-away species—there is a connection.

Jennifer Angus, who teaches textile design at the University of Wisconsin, became an amateur entomologist in the course of creating her “;Victorian Fancy”; series of dollhouses and installations. She builds scenes of perfect domestic felicity, but all the patterns on the walls, floors and furniture are arrangements of beautiful insects, and all the characters in the dollhouses are insects, too—electric-green beetles from Thailand, locusts from French Guiana with spectacular wings of purple and blue, striped weevils, polka-dot weevils, leaf mimics, white cicadas and frog-legged beetles that look like their name. “;I wanted to create a pattern that suggests a domestic space,”; she said, “;but of course the one thing people don't want in their house is insects.”;

Angus hopes to change people's arthrophobia, to “;rehabilitate the image of the insect,”; organisms without which our crops would not be pollinated or our detritus decomposed. Some viewers will ask her, if you love insects so much, why sanction their killing? Hundreds of beauties died for the sake of your fancy! Angus will reply that she uses only adults. “;They've had a chance to procreate, and most species don't live long after they've reached the adult form,”; she said. “;Some of them don't even have the mouth parts to eat.”; If you're really concerned about the future of tropical insects, she will say, get involved in tropical forest conservation. Insects reproduce quickly, and they'll do fine as long as their habitat is intact.

Of course, people have always used natural materials to make their art, for the simple reason that until recently nature was all they had, said Ellen Dissanayake, a scholar on the evolution of art and author of “;Homo Aestheticus: Where Art Comes From and Why,”; among other books. Yet from the beginning, art demanded transformation. “;Even in hunter-gatherer societies, they tend to make their stuff look not organic,”; she said. “;When they're painting, they'll use geometric shapes, make a row of triangles or circles, as though to show humans are more than nature.”; A chieftain in a traditional society may wear a headband of fur, feathers and the iridescent green carapaces of beetles, she said, “;but all those carapaces are carefully lined up.”; As Dissanayake sees it, when people make art, or “;artify,”; they follow several “;aesthetic principles,”; whether they know it or not. “;They simplify, repeat, exaggerate, elaborate and manipulate expectations,”; she said.

In fact, many works of organic art hew closely to Dissanayake's artifying code. The New York artist Tracy Heneberger, for example, created what looks from afar like a kind of samurai shield by arranging 1,155 sardines in a series of concentric circles and then applying multiple coats of shellac.

He got the sardines from a dealer in Chinatown, and it was a challenge, he said, finding ones of just the right length, width and straightness that still had eyes in their sockets. Helen Altman of Fort Worth used a plastic model of a human skull purchased from a medical supply catalog to mold spices, seeds, grasses, beans, lotus leaves and the like into firm, skull-shaped packages, which she then arranges on a wall in a roughly 6-foot-by-7-foot grid. She wants viewers to approach and stick their noses into the skulls, breathe deeply of the clove, the rose, the balsa, and let death get in their face.

“;It's like the traditional sugar skulls you see in Mexico for Day of the Dead,”; she said. “;You make death into a sweet thing to be eaten so that people don't fear it.”; Lonneke Gordijn and Ralph Nauta of the Netherlands gathered dandelions, removed the puffy seed heads and then painstakingly glued each seed head back on; those reinforced flowers were then outfitted with LEDs and wired together in cube frames to create almost viral-looking stacks of modular dandelion lamps.

“;People have this image of the dandelion as a fragile thing, you pick it up and it's gone,”; Gordijn said. “;But it's not gone. Those parachutes blow everywhere and grow everywhere. That's how the dandelion reproduces.”; The dandelion lights, she said, were designed with a similar eye on tomorrow: electronics and nature, bootstrapping each other into the future.

Fish shields, powered flowers and fragrant skulls: simple, elaborate, unexpected, exaggerated, and cycling and recycling, like a chant, or like life.