Living Harmoniously

For the past two years, I have been greeting a house spider (Kukulcania arizonica) who has been living in my garage. She has taken up residence in a crack in the frame of the door leading into the house, and every evening as I go into the garage to get a can of food for my dog, I say “Hi Spider!” She usually responds by scuttling away into her crack, probably because of the vibrations of my voice on her web.

Sometimes, however, when she has caught something, she sits on her web eating, oblivious to my presence. Then I can crouch down to within a few centimeters of her and study her in detail. She is a satiny black, with long legs and a somewhat bulbous abdomen. Although she usually comes out only at night, when she is lost in her food she can keep feeding into the daylight hours, engrossed in sucking out every last scrap of fluid as if she did not know where her next meal was coming from.

The last winter was pretty cold in the garage, and I would see her sitting on her web night after night, waiting patiently for some unwary insect to stumble in. But there were no insects out in the cold. She seemed to shrink in size as the months passed, causing us to worry about her. I thought of trying to feed her, but then decided that I should let nature take its course and let her survive by her own efforts. Fortunately, she made it. Now that it is summer, insects are in plentiful supply, and many evenings I see her munching on a cricket or a beetle that she has snared in her web.

She is the longest animal resident that I know about, but there are many other animals who share our house. Little black ants (Monomorium minimum) have a nest somewhere underneath the foundation, and occasionally make their unwelcome presence known by marching in long columns through the kitchen in search of food when there is nothing to eat outside. Tree Lizards (Urosaurus ornatus) run around on the outside walls, retreating into crevices and spaces under the roof as the cold of winter sets in. An Ash-Throated Flycatcher family (Myiarchus cinerascens) nests in a hole under the eaves, with the parents faithfully bringing back an astounding number of insects for the hungry nestlings. Paper wasps (Polistes) have nests in places where the eaves have slightly come apart. I am sure that there is a plethora of other animals who live in the house without my seeing them or knowing that they are there.

Our houses provide habitat for whole communities of animals. Most of the time, everyone lives in relative harmony, until and unless the population of a particular species grows out of control, much like a disease infecting a person. Then things get out of balance for a while, but the community regains its equilibrium in relatively short order, and harmony is restored.

And when you think about it, our bodies have the same kind of function for a variety of organisms. We have a number of bacteria living in our guts and elsewhere. We have fungi occupying various parts of our bodies. We have mites living in places such as our eyebrows. Most of the time, we are not aware of any of these residents, unless the population of a species using us for food or shelter spirals out of control. Then our immune system kicks in and restores the harmony of coexistence in our bodies.

Just like my house, my body provides food and shelter for lots of different organisms. We all live in harmony, sharing the natural world.

Comments

[zhakee]

I used to have a kitchen spider that lived in a corner of my kitchen window for a year. When its web got too big and filled with unsightly stuff for me, I'd knock it down. By the next day the spider would have a new, tidy web up and ready to catch any fruit flies. Your blog is quite nice, the insight in your commentaries, refreshing.

[Chris Wemmer]

My colleague, Mike Robinson, made me aware of the fact that spiders can become fat. (I'm sure you are aware of this--but a little zootrivia never hurts). He studied the orb weaver Nephila in New Guinea, and learned that Papuans roast the big spiders in bamboo tubes. When hot and juicy they make a nutritious snack.

I must say that from a zoologist's perspective, "old diseased houses" are the most interesting, if not the best human habitations.