Christine Schoene Maccabee
The Mysterious Lives of Insects (Part 2)
coon (size of a large lemon) attached to a twig down by the chicken coop. I feel lucky to have even seen it, as it was covered with dead leaves and looked like nothing special. However, having seen such cocoons in years past, I recognized it immediately as that of a magnificent large moth. Excitedly, I broke off the twig and brought it up to the porch, where I stood it upright in a sturdy container for observation.
With the warmth of early to mid-spring, one of three moths will emerge from this cocoon: it may be a Cecropia or a Polyphemus or Promethea. I am excited to see what it will be, but until then it remains a mystery.
I have found in all my years of observation and discovery that most things we take for granted in nature happen in secret. Not unlike most creatures, including the human creature, insects have very private personal lives. Not only that, they are all specialized with particular talents, and most of them make significant contributions to the quality of life as we know it on this amazingly mysterious Earth.
In my column last month, I left the reader hanging when I said that bees have “stinky feet.” With my apologies to Dr. Dave Goulson1, who discovered this peculiar trait in bees, I will proceed to explain why bees have “smelly,” not stinky, feet. Smelly is not always stinky. Sorry, Dave.
So what does Dr. Goulson mean when he speaks of smelly feet? As he was observing the behavior of bees in his extensive meadows in France, he found that bees are very particular as to which flowers they feed on. Not only do different species of bees specialize in specific types of flowers to suck, but they seem to know, somehow, whether a particular flower has recently been fed on by another bee. Perhaps you have observed in your own gardens bees hovering by a perfectly fresh looking flower, but passing it up for another. I know I have seen this, and often wondered about it.
Dave Goulson set about the “fiddly business” of measuring the quantity of nectar in the rejected flowers, and found that they had less nectar in them than the chosen flowers. Somehow, bees knew which flowers had the most rewards, but how were they doing it? Much like we humans, bees are very busy and have no time to waste sucking dry flowers. Of course, the flowers they reject eventually create more nectar, so perhaps that same bee will come back to suck later.
Now we have two mysteries to solve. First, why are bees in such a hurry with no time to waste (in other words, busy)? And what are those smelly feet all about anyway?
First of all, in flight, a bumblebee flaps its wings two hundred times per second, according to bee experts like Dr. Goulson. This generates a lot of heat, which it needs to keep its body temperature at least 30 degrees Centigrade; but, of course, this comes at a cost: bumblebee flight is enormously expensive in terms of the energy it uses. A bumblebee with a full stomach is only ever about forty minutes from starvation, so it cannot waste energy sucking at dry flowers or it may perish before the days end. So you thought it was difficult being a human when the car breaks down and you have to put hard earned money and precious time and energy into fixing it. I guess bees and humans are not so different after all!
But what about those smelly feet? As it turns out, after examining the feet of bees, Dr. Goulson discovered that every bee—in fact, every insect—leaves a trace of oily liquid wherever they go. Bees, even butterflies, leave a footprint wherever they land, which is then detected by the antennae of other pollinators. Antennae of insects are finely tuned for detecting the oily traces and can readily “smell” just a few molecules in the air around a flower and on the petals themselves. This amazing built-in mechanism saves the bee time and energy that would be wasted climbing inside empty flowers.
I must confess, now I am worried more than ever as to how lawn chemicals and herbicides might interfere with, and even kill, these important, sensitive, insects.
There is much about the natural world most of us do not know, and what I have written here barely scratches the surface.
I don’t know about you, but I will never look at my flowers, and the insects that depend on them, the same this spring and summer.
So, enjoy the emerging beauty in your gardens and the world at large. And never loose your curiosity or your sense of wonder, for that is equally a part of our natural heritage. Even smelly feet!
1Dave Goulson’s entertaining and informative books, A Sting in the Tale and A Buzz in the Meadow are available at our library.
