Earth

This is a reprint of an entry I did for an Abecedarium project in 2004*. I have edited it to remove the word "the" when referring to Earth (David William Fischer pointed out that no one says, "The Mars"), and to remove a sentence about exoplanets.


Earth is the only object in the Universe known to create and sustain life. Our point of view is biased: Earth is our home and mother. The size of the Universe gives us hope that there are other, similar places, that life can occur again and again. Our limitations prevent us from proving this, however. We can stand on her surface and point telescopes into the void, and we can even send small craft away from her body to transmit information back to us. Distances in space prevent us from ever visiting a planet outside of our Solar System.

How Earth created life is not understood. How she sustains life is the more important mystery. We don't really know to what degree human activity is disrupting Earth's ability to sustain us. My belief is that we may destroy Earth's ability to sustain our species (and the species that have come to depend on us) but we will never destroy her ability to sustain life itself. The important thing to know, is that if we can not live on Earth we have no where else to go.


*never did finish that abecedarium.

100 Species #63: Toadflax brocade

Alexis found a pair of these caterpillars (Calophasia lunula) over by the main perennial beds.

I could simply call this the "toadflax moth caterpillar," but that would deprive us of the pretty and ornate common name "toadflax brocade." Toadflax is the weed in the snapdragon family that the caterpillar feeds on, and brocade is someone's fanciful idea of what the caterpillar's pattern looks like. This European insect was deliberately introduced to Canada in 1960, and to the west coast of the United States in 1968, to help control toadflax.

I don't mean to unduly criticize the agencies responsible for releasing this animal on a new continent, but it appears to me to be a poorly thought out decision. The caterpillar has a single host plant, so is unlikely to eliminate it. For example, gypsy moths can eat many different plants, and so huge numbers of them can actually have an effect on the ecosystem; if the toadflax brocade was to eat ALL the toadflax, they would quickly eat themselves to extinction. The adult moth feeds on the nectar of many plants including toadflax, meaning that the moth plays a role in pollinating and therefore sustaining the population of its caterpillar's host plant.

Since the larva only feeds on toadflax, which is itself an alien invasive, there doesn't seem to be any downside to the release of this non-native species in North America. In fact, you can apparently still get them if you would like to try to control toadflax with them.

This entry probably holds the record for the most dense usage of the word toadflax in the history of the internet.

100 Species #64: Common whitetail

This female common whitetail Plathemis lydia was resting on the fence of our little yard.

There is a swampy area a few hundred feet from our house, and Turtle Pond and Stony Brook are not far down the road. Still we were surprised--but gratified--to see dragonflies hunting in the yard. Dragonflies are active predators, catching other insects in flight. Male common whitetails have fat bluish-white abdomens, but as when this animal was 100 urban species #32, I have photographed the less distinctive female. Spots on the wings caused me to misidentify it as a 12 spotted skimmer, despite having seen the species before.