June 12th, 2010

dandelion

50 More Urban Species #15: antlion



Antlion. Family Myrmeleontidae.

Some of my first memories of interacting with the natural world involve antlion larvae. The soft-bodied but formidably mandibled creature lurking at the bottom of a slippery sandy pit, waiting for a hapless victim was a great reward to the imagination of a child interested in nature. I remember a distinct disappointment while watching Return of the Jedi, that the Sarlacc, clearly designed as an antlion writ large, did not have huge pinching jaws. (It was the beginning of a pattern of being disappointed by George Lucas decisions that has continued unabated to today, but that's another subject.)

Then the antlion was at the center of an epiphany I had (and wrote about here), which I can summarize for those who don't wish to read my ramblings from six years ago: Even the smallest human actions can alter the natural environment, and favor certain species over other. Shield a small area from the rain, in a rainforest (in my example), and you create a small sandy area, which attracts antlions. It's the basis of the study of urban ecology, and the reason why when I say "urban," I'm really thinking about any place where the hand of man has altered the landscape in any way to favor certain organisms over others.

In "The End of Nature," Bill McKibben points out that since human activity has affected the make up of the atmosphere of the Earth itself, that there is no place on the planet that can not be said to be free from human influence. That "nature," as defined as that which is apart from humans, does not exist any more, at least, not here. Of course, humans evolved on this planet as naturally as any organism, so defining nature that way is pretty self-centered and at odds with science. It is a useful construct, however, in as much as it helps us figure out how we are altering everything else on this little planet, which by the way is still the only place we or anything else we know of can live.

Antlions, under the rainshadows of eaves and ledges, dig their little traps and wait for ants and spiders and other little creatures not blessed with wings or the wherewithall to use them in a crisis, to blunder in. They then chop them up with their scary jaws, and secrete digestive juices onto them, and suck up the result. Antlion parents need to choose locations to lay their eggs wisely, but if the larva finds itself far from prey, it can survive up to three months without a meal. The adult antlion looks a bit like a damselfly but has distinctive clubbed antennae. In all my years of playing with bugs, I have only found two adult antlions. Here is the first.

For reasons that are arbitrary and hard to describe, I suspect the species of antlion whose larva I'm holding in the picture above is Myrmeleon immaculatus, but I can't say for sure.