Over the years when leading hikes, I would often get many of the same questions about nature. Two of the most common came after explaining some aspect of ecology; how this plant needs that bug for pollination or how wetlands are needed to sustain a multitude of species. Suddenly a light bulb would come on about this web-of-life concept and someone would blurt out, "Well then, what good are mosquitoes?" This, usually after too long swiping them from their face. Or someone else would ask, "So, what is the point of poison ivy?" I actually loved it when these questions would come up, even if some folks thought they were being clever. It gave me the opportunity to continue to expand of the interconnectedness of things...things they could relate to.
So, I would explain the importance of mosquitoes at the low end of the food chain for aquatic life, bats, birds, etc. The poison ivy question was a good stepping off point into the area of how anthropocentric we can be...something can't be good if it is not good for humans. But poison ivy berries are delicacies for some birds (not to be too anthropomorphic about it :), and one of the first foods birds consume in late summer. I would always recommend that if people had poison ivy on their property, and it wasn't in a place where others could get in to it, they should leave it for the birds. Not many takers on that one, though.
I've also led a few night hikes, mostly full moon hikes or took kids out to hear owls, spark Lifesavers in our mouths in complete darkness and watch fireflies. I don't think I've ever had anyone ask, "What good is a firefly?" But it is a really good question.
The larvae of fireflies, sometimes called "glow worms," do feed on worms and snails...but adults merely feed on each other...or maybe nothing at all. Scientists are not quite sure. And adults, like the Monarch butterfly, have an unpleasant taste they produce if attacked, which comes from drops of blood. Consequently, they have few predators, and are not really part of the food chain, per se.
As a someone who dwells in both the worlds of science and faith, I love it when every now and then something is unexplainable, except that it is a gift of sheer beauty and wonder. If someone were to ask me what fireflies are good for, I would have to say I don't know. I just know that when I see the first ones in summer I am thrilled - transported back to some of the fondest memories of my childhood. And in the middle of summer, standing on the deck at Prairie Pond Woods, looking out over the prairie, I am dazzled. Someday, an entomologist may discover their ecological purpose, but until then I am content to leave the question unanswered...and just watch.
I hope you will take a minute or two this long weekend to look for "lightening bugs" in your backyard or at a park. They are fascinating and complex creatures...and becoming harder and harder to find. To learn more click here.