Nature at its most imaginative. Or maybe, nature re-imagined and re-examined in unlikely and delightfully improbable ways.

That's the common thread running through the art of Pam Johnson, Janet Kastner and Naomi Schlinke in "Bioforms," a jewel of an exhibit now on view at D. Berman Gallery.

In essence, each artist could be linked with the grand tradition of nature painting (nature art, really) -- that eternal fascination artists have with the form, beauty and wonder of the natural world and from which comes everything from still lifes to landscapes to nudes to botanical studies.

Houston artist Johnson offers up drawings and balsa wood sculpture that are at once mysterious and familiar. Her dark Conté crayon drawings vaguely recall historical botanical drawings, known for their sense of preciseness and accuracy. But in Johnson's work, what is it that we are actually looking at? Seeds? Pods? Something perhaps microscopic or sub-cellular? Perhaps not a plant form but an animal? Or perhaps a combination of both. I think it's likely the latter.

That combination is obvious in "A Propagating, Spinal Clavicular Swell." This balsa wood sculpture looks part walnut, part gourd, and yes, part human anatomical form, with its skin split open to reveal pocked seeds. Then there's "Strange Clusters IV," a cluster of balsa wood shapes which hangs by a vine from the ceiling. Sensuous and elegant, the shapes defy exact classification.

Kastner, who teaches ceramics at the University of Texas, trades on a similar sort of ambiguity though most of her forms reference the body. Her porcelain sculptures are simultaneously luscious with their sheer smooth surfaces and also dangerously fragile. Some of Kastner's sculptures are realistic, such as "Teeth," two rows of eight hand-sized teeth that are neatly fixed to the gallery wall. Like in many of Kastner's wall sculptures, the shadows cast by the pieces are an integral part of the overall image. "Teeth" is both clinical and also familiar.

"Jacob's Pillow," on the other hand, leaves reality behind. What to make of the creamy half-rounds decorated with floral decals that form the undulating pillowlike shape? Are they strange pastries? Some kind of larva or egg? Again, precise identification eludes us in a tantalizing way.

Austin painter Schlinke plays with motion in oil paintings, riffing off her background in dance. Again, there are the strangely familiar and yet unfamiliar forms. In Schlinke's can-vases, they seem to float in and out of richly colored backgrounds like objects in water or like the lush, swirling movement of clouds. At first glance, Schlinke's paintings seem calm. But they're actually not -- they vibrate with subtle movement. Take "Afterimage," with its large expanse of green floating with amorphous shapes. Schlinke gives the shapes a sense of motion by adding slight shadows to their outlines, as if the movement of these strange forms was caught in the moment, out of focus with all the resulting ambiguity.