Bill Dunson, born in rural Georgia, skipped 12th grade and went directly to Yale. Bill subsequent-ly received a PhD in Zoology from the University of Michigan, studying softshell turtles. Bill is Professor Emeritus of Pennsylvania State University thanks to a career spent entirely at that institution, teaching and doing research on the physio-logical ecology and ecotoxiciology of reptiles, amphibians and fish. Always curious about nature, Bill has dedicated his life to learning and sharing his knowledge with others. He has served on many advisory boards here in Southwest Florida to preserve the water that gives life to our region.

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Click for a larger view of the Pink Swamp Milkweed , Hibiscus, Pickeral Weed, Mockingbird Nest

Natural Patterns Observed on a Morning Walk.

Many of us gain great solace from walks in the woods and fields observing and communing with Nature. Each of us may be more or less analytical depending on the day's mood or the locality. Some days you may just want to contemplate the overall beauty of the scene, rather than making hypotheses about the patterns observed. This morning I strolled around some of the fields and ponds on our Virginia farm looking specifically for interesting natural patterns that would be an integral part of the adaptations of plants and animals.

A beautiful pink swamp milkweed was in bloom and had apparently attracted two wasps- yet on closer inspection the larger "wasp" was actually a ctenucha tiger moth that is able to fly in the daytime by mimicking a wasp. So consider the amazing process by which the color, shape and behavior of this moth changed to deter birds from eating it. Of course the milkweed itself is the center of a group of insect species that have adapted to eat its poisonous leaves and to use these toxins as protection against predators (monarch butterfly, milkweed bug, several milkweed beetles).

Another flower seen was a large hibiscus, white with a red center, that would appear to be attractive to nectar-loving insects, yet its primary visitors are specialized bumblebees that collect only pollen to feed their young that are reared in underground tunnels. The red center is often called a "nectar guide" although its purpose here must be to guide the bees to the vicinity of the pollen.

A blue flower in bloom in a pond was pickerelweed which attracts a variety of small insects including several species of skippers. The old flower stalks which are going to seed undergo a remarkable process whereby the stalk bends down into the water to release the floating seeds for dispersal.

Finally I noticed a bird nest in a viburnum bush and recognized the speckled eggs as those of a mockingbird. The cryptic coloration would be useful in protecting the nest from discovery by aerial predators such as crows. Nearby tree swallows and bluebirds nesting inside boxes have eggs of pure white and blue respectively. So the egg color both reflects where the nest is made and its need for protection, and some other factors such as the group to which the bird belongs. It would be most logical for hole-nesting birds to have white eggs, and thus bluebirds have no need to have colored eggs, but have blue eggs as do many of their relatives the robin and other thrushes.

As you encounter Nature you will observe many such patterns, some of which may have clear explanations, and others may not. But I find the observation and contemplation of such intricate and complex patterns enhance the experience of interacting with Nature. Just remember that the study of ecology is not rocket science, it is much more complicated!

Bill Dunson
Galax, VA & Englewood, FL

See my blog in a local VA paper at:

http://www.galaxgazette.com/content/natural-patterns-observed-mornings-walk