Lydia Mackay
4/14/98
Dr. Clark
Animal Life
Article Summary #2 – Beetles
When you think about beetles, little bugs that crawl around come to mind. The fact that North America has almost 1,500 different species of beetles, and the world has more than 30,000 is an amazing fact. And those numbers make up only one family of beetles, more than 150 other beetle families exist. In fact, about one of every four animal species known on Earth is a beetle. Needless to say with beetles being the most biologically successful species in the world, there are probably many thousands of beetles yet to be discovered.
In terms of their variety, do beetles have the greatest success story in the history of life? The answer to this question may very well lie in their defining characteristic: the elytra which covers the abdomen and the wings is like a hard case, and over time these covers grew stronger and more streamlined so that beetles quite literally became like little fortresses. This elytra also has the ability to store air, which helps some beetles breathe under water. When you think about it there is really no steel or modern plastic that could match the combination of strength and flexibility of an exoskeleton made of chitin, which is a polysaccharide similar to ordinary cellulose. Another feature which I found interesting about beetles, was that their equivalent of roaring was to loudly rub their wing covers. So watch out!
Beetles food sources rely on things such as leaves, roots, wood, fungi, or plant debris. With the up and coming new forms of vegetation, this meant and still means new opportunities for beetles, in that these insects can proliferate into an almost superabundance of forms.
At this point I’d like to mention some beetles in particular that I found interesting in this article. The Metallic Wood-Boring beetle, is often called the jewel beetle because of its dazzling iridescence which makes it a favorite among collectors. Their feeding habits just so happen to help deplete the wood in forests worldwide. The Weevil superfamily which makes up 8 families, are known as major crop destroyers because they chew into nuts, seeds, and plant stems. One of the most interesting species is the giraffe weevil which has a very long, jointed neck much like a giraffe. One of the most peculiar looking beetles is the Long-Horned beetle. The antennae which extend from their heads can approach or even exceed their own body length. They are known to be recyclers of dead plants. And lastly, one other fascinating beetle is the Scarab beetle. It is essential to the ecosystems of the world, because these beetles recycle plant matter and feces. Although some of them are brilliantly colored, it was a black dung beetle that ancient Egyptians revered as sacred. To them it meant a sacred symbol of rebirth, ever emerging from the ground.
So you see, beetles have proved invaluable in the control of damaging insects and invading weeds, and they continue to be major pollinators. Overall I think beetles are pretty interesting little creatures, and if they help our ecosystem then I say more power to them.
SOURCE: National Geographic, Vol. 193, No. 3, March 1998. Planet of the Beetles, by Douglas H. Chadwick. Pgs.100-119