Insects are the most numerous organisms on the planet. They can be found in virtually every ecosystem in the world, with the possible exceptions of the polar regions, and the deepest, airless parts of lakes and oceans. They have evolved to live in whatever habitat they find themselves in. Their diets are nearly as varied as their species. Nearly half of all insect species are herbivorous, eating on only plant life. Many of these favor certain plants, and may cause severe damage, such as bark beetles in a coniferous forest.
Mantis contributed by Nancy Maurer
Carnivorous insects are divided into two categories. The first, such as praying mantises and lady beetles, actively catch and eat other insects. We consider these to be beneficial insects because they eat the insects that destroy our prize ornamental or agricultural plants. The other category of carnivorous insects are parasites, which live in, and consume the bodies of their hosts, such as the larvae of some wasp species which lay their eggs on, or inside the body of the prey, literally eating them alive, from the inside out. Sounds gruesome, doesn’t it?
Still other insects are characterized as detritivores because they eat the rotting remains of both plants and animals. This may sound gross, and these insects may be regarded as disgusting, but they are all essential to a healthy environment.
Imagine what our earth would look and smell like if all the dead things were just lying around, not being helped to decompose and make way for new plants and animals to grow.
A big portion of the insect world are the beetles (coleoptera), the largest order in the entire animal kingdom. Beetles can be fascinating. Many are brightly colored and quite pretty. The ancient Egyptians regarded one species, the scarab beetle, as sacred. Some grow to be huge, (over two inches—huge for an insect), others quite small. Like other insects, their diets are varied, as are their habitats. Also, like other insects, some are regarded as pests, and some, beneficial. Some species have been used as an environmental control for harmful insects. This may not work out well, if they are not native, since without natural enemies they may become a problem.
Pleasing Fungus Beetle
Several species of beetles eat only fungi, algae, or lichen. Of these, one of the most interesting is the Pleasing Fungus Beetle (Gibbifer californicus). Yes, that is really its name, and no, it does not live in California. However, it is native to the central highlands of Arizona, and is often observed near streams and in forests during the summer. The pleasing fungus beetle is smallish, ½-3/4”. The beetles seen in this area are a lovely shade of blue. They feed on fungi, where they also lay their eggs, so the larvae have a food source. The adults can be observed walking along the ground, or on tree trunks. They are also capable of flight, and are quite friendly, having been known to land on unsuspecting hikers. There is no denying that insects play an important role in the circle of life. Next time: More interesting insects!
Contributed by HCNH Naturalist Sandy Stoecker