Wednesday, November 16, 2011
A Desert Visit
It's now late Thursday. Ironically, I was pondering a narrative about my trip through the desert off and on all day Wednesday and was thinking about teeth. Today, I visited my dentist, and that cinched it. You see, the technical name for the sagebrush is Artemesia tridentata, so named because the distal margin of each leaf has three projections that resemble teeth (to imaginative botanists anyway). The second photo shows the teeth (i. e., dentition) in a canid skull. I was in too much of a hurry to determine if it was Coyote or Dog. Besides telling my dentist about this blog post, I told him that Dandelion is a compression of the French "dent de leon," tooth of the lion, or lion's tooth, after the "dentate" margins of the leaves. We were having fun sharing the large amount of dental terminology that overlaps that of plant taxonomy.
What struck me about this particular brief visit to the desert was the difference between viewing it at highway speeds vs. getting out and walking around. First, the fragrance of the Sagebrush is impressive - only apparent while driving during specific conditions of temperature and humidity, but always pleasant and powerful when walking among the bushes. Second, one immediately stumbles across evidence of a great deal of animal activity, most of which takes place at night. I think the droppings in the fifth photo are jackrabbit, but they could be deer. I'm not an expert in scatology. The ant hill was impressive. It was a very cold morning, so when I poked the hill with a stick, it didn't arouse any ants. On a hot afternoon, sometimes a single poke with a stick will cause an explosion of ants. I've even seen an ant stampede erupt in response to a little foot stomping from several feet away from their hill. This brief roadside stop brought back memories of exciting times spent in the Sonoran desert from the Mojave to western Texas. Traveling at night with a flashlight is the most exciting, although one does need to watch out for rattlesnakes. Many different kinds of animals spent their days underground and walk and crawl about on the surface at night. The Spadefoot Toad spends most of each year underground, but emerges during the slightest of spring rains to breed. Their rate of development from egg to adult is quite adjustable according to the rate of evaporation of the puddles in which the eggs are laid. The process can take as little as a week. Even though the desert north of Reno is only an hour from my home in Quincy, it is literally another world as it is on the eastern side of the Sierra crest, a rain shadow, and supports literally hundreds of species of plants and animals that are not found around Quincy. One of the things I love about studying natural history in Plumas County is the proximity of so many different biological communities by traveling only an hour or so east or west, or getting off the main highways and experiencing a range of elevations from 2,000 in the lower Feather River Canyon, to many peaks that exceed 8,000' to Lassen Peak, at the northern tip of the county at 10,400'. Also, it is in this county that the Sierra meets the Cascades. Many different species have the northernmost or southernmost extent of their range in this county.
One last thought about teeth. I've always found the dentists' system of numbering our teeth from 1 to 32 rather boring compared to the zoologists' terms: incisors, canines, premolars and molars. In canines and felines these four categories of teeth have much more differentiation of shapes and functions than human teeth. For my comparative anatomy class, many years ago, I did a term paper on mammalian teeth. I collected many skulls in the forests and swamps around New Orleans, Louisiana, then visited slaughterhouses in Massachusetts when I went home for Christmas. My paper included ink line drawings of every skull with emphasis on the similarities and differences of their teeth. I still have the paper; in fact, this year the paper is fifty years old! I think I'll dig it out of my file cabinet and reminisce.