Do not disturb

A stink beetle, Eleodes armata, is wandering in the oak duff. I can hear it scratching against the smooth backsides of leaves.

Up and over all obstacles, at times this creature commonly called a stink bug flips onto its back when attempting to negotiate too steep an incline. Its long legs wave in the air until they grasp something for leverage.

Back on its feet, the stink beetle comes to rest near a green leaf. Slowly it wraps its legs around the leaf, positioning its dinner just perfectly so the beetle's mandibles can grasp the soft plant tissue. The plant bends to the bug's tug, and I see the chewing that ensues.

I go about my business but keep the beetle in the corner of my eye. Ten minutes later, the beetle ambles off, and I take a close look at the leaf. There, where the beetle had been eating, are super-tiny ridges left in the margin of the leaf. Something I never would have noticed had I not watched it happen.

Though this took place several days ago, the beetle's journey keeps coming back to me, especially the marks that it left on the leaf. This beetle has somehow left me feeling tiny.

Because of its minuscule actions and the microscopic sign it left on the leaf, I have become more aware of the vastness of the universe. There is so much that goes unnoticed, so many subtleties not witnessed. It makes me aware of how much truly goes on each day, and this was all brought about simply by seeing a beetle eating.

Although beetles have existed for millions of years, we have a detailed record of their existence in Los Angeles 10,000 to 40,000 years ago thanks to the discoveries in the La Brea Tar Pits.

Of the thousands of insect specimens recovered from their tar graves, beetles were among the most common.

The ancient aquatic beetles, families Hydrophilidae and Dytiscidae, were probably lured into the pits by the thin sheet of water that covered the sticky asphalt. Carrion beetles, family Silphidae, were also preserved, caught feeding on decaying animals mired in the tar.

Many ground dwelling beetles of the families Carabidae and Tenebrionidae were trapped there as well.

Strength in numbers

Beetles belong to the insect order Coleoptera, the largest order in the animal kingdom, more than twice the size of the next largest order. Coleopterans usually have two sets of wings, forewings and hindwings.

The forewings are modified into hard leathery coverings called elytra. The elytra meet in the center of the back forming a straight line. This line down the back serves as an identifying characteristic of Coleoptera. In many species the hindwings are missing or greatly reduced, and they are therefore flightless. Coleopterans have well-developed mandibles and mouth parts adapted for chewing and biting.

Coleoptera have a wide range of diverse traits and are found in nearly every habitat. They eat a variety of foods, from plants to carrion to other insects. Some beetles are known to be parasitic or predacious. In California there are at least 7,000 known species of beetles, many still unidentified.

Night life

The stink beetle is a member of the darkling ground beetle family, Tenebrionidae, that feeds on plants at night. There are approximately

400 species of this family in California and around 100 species in this genus.

The stink beetle is a shiny black bug that grows to a length of 17 to 33 millimeters. The forewings are fused on the midline and taper to a point on the poste

rior edge, making

flight impossible. The beetle's long legs display prominent spurs.

Stink beetles are widespread in this state, found in arid areas in Southern California to the Central Valley. Along with other species in this genus, the stink beetle is known for standing on its head when disturbed and emitting a strong, unpleasant odor.

Eggs are laid in the soil during spring. The larvae in this genus are brown and cylindrical, having a pointed last abdominal segment. Through complete metamorphosis, the larvae eat seeds, roots and herbs. Adults are general feeders.

Another often seen darkling beetle is the wooly ground beetle, Cratidus osculans. It is smaller than the stink beetle, only growing to between 12 and 16 millimeters. Unlike the smoothly tapered stink beetle, the wooly beetle is boxy and covered with reddish brown hair. This beetle is found in chaparral along the coasts from Southern to Central California.

In the beetle world there is a vast array of morphological and behavioral adaptations. From this diversity my mind trips off to the prey and predators of these beetles.

I wonder at the lives of the birds and plants and envision the delicate web to which we are all connected. Endless questions follow.