Animal Phyla

Introduction

A 1600 Work I

1600 Work II

1600 Work III

Nematomorpha

Arthropoda--Ants

Arth II--Reduviidae

Chordata--Sharks

Chordata-Sharks II

Chordata--Ratites

Mollusca--Slugs I

Mollusca--Slugs II

Animal Phyla--Introduction

Bill Long 4/25/07

Opening Up Worlds and Words

This essay begins my plunge into the wonderfully complex but illuminating world of the animal kingdom. Well, even that designation (i.e., kingdom), which so long held sway in biological taxonomy as one of the most inclusive categories, has been supplemented or superseded in the past 17 or so years as the "highest" ranking in the Linnaean nomenclature system now is a domain: eukaryote or prokaryote. I will discuss those terms as these essays progress. Suffice it to say that biological taxonomists at present "divide the world," so to speak, into the following categories: (1) Domains--eukaryota and prokaryota; (2) Kingdoms--under the eukaryota we have the animals, plants, fungi and protists, while under the prokaryota we have bateria and archaea. Just to make the picture more complex even before we begin, biologists have also posited many steps between domains and kingdoms which will come in for mention sooner or later. Biologists also talk about "clades" and "cladistics" today, which I will get to and explain as soon as I understand them fully enough!

As you know doubt know, our present classification system owes its origin to the brilliant Swedish botanist Carolus Linneaus, whose 300th birthday we celebrate this year. When the world was much more simple, or modern science was much less developed, Linnaeus developed a fivefold classification system for all living things. Kingdoms stood atop the world, followed by Classes and Orders and Genera and Species. He did most of his writing in the 1740s-1770s (he died in 1778). When I was growing up and studying high school biology in the 1960s, the classificatory system I learned was sevenfold: Kingdoms, Phyla, Classes, Orders, Families, Genera and Species. Since that time (and even prior to that, as I am now learning), taxonomists have invented about 20 other categorizations that can sometimes be used to make more precise a particular identification. We will no doubt run into some of those as these essays progress.

Yet, the more we study the animal and plant world, and the more technological progress we achieve (DNA evidence being the latest advance in taxonomy), two things are becoming clear: (1) the location of thousands of species, families, and orders in our taxonomical system is "up for grabs" again and (2) that biologists have discovered, in the last 30 years, almost as many more species of living things as were classified in the previous 200 years. That is, in animal species alone we have classified or identified nearly 2,500,000 species. More are being discovered (and threatened, by the way) almost every month. Thus, the diversity of the animal and plant kingdoms or, to speak more 'modernly,' of the domains of life is a constant gift and challenge to our limited but curious minds.

Reasons for The Study

I am undertaking this study at this point for three reasons that I can readily identify. On the one hand, I would love to become more acquainted with the amazing diversity of life on the planet. All you have to do is take out a picture book on Primates from the library to learn how beautiful, strange, alluring and diverse is this small subset of the world of living and motile creatures which we inhabit. If you have a mind to learn a lot, then the biology of plants or animals (or other things) is a wonderful world to explore. Second, studying the world of living things will give you, literally, a humongous vocabulary. If you want to do it "right," you will have to learn the countless Greek and Latin-based terms that are the basis of the classification system. This is a wonderful discipline, and you will also learn incredibly interesting stories thereby. You will learn, for example, that the Gordioida, a class of the Nematomorpha (a phylum of parasitic horsehair worms), received their name because some biologist saw these tangled critters and decided that they reminded him of the mythological story of the Gordian knot, which Alexander the Great was supposed to have cut, thus presaging that he would rule Asia. So, by learning the Greek and Latin roots of the living things, we often will be thrust back into worlds which we should know something about but are lacking in precision and depth of knowledge.

One more word on words. I discovered, through making a large chart of the Animal Phyla (which underlies this study), that several of the phyla names give birth to English words that are frequently used in spelling bees and other educated venues in our culture. For example, one of the phyla, the so-called velvet worms, is called Onychophora (approx. 110 modern species; literally means "claw-bearer"). The first word I missed last year in the National Senior Spelling Bee (where I placed third) was onychophoran. Had I engaged in this study earlier, the word would have been a snap. Or, to take one more example, we have the phylum Ctenophora (lit. "comb-bearer), the 100-species comb-jellies. I will speak of them below. The "c" is silent, and so almost everyone misspells it, unless you know the word or the group to which it points.

Third, studying the names and actions of living creatures gives you a ready store of examples about human behavior. This may be more important to preachers or others who regularly speak on human behavior, but I find it incredibly useful in conversation or in my attempts to understand human nature. It is far better to say that a person is a certain kind of parasitic worm, when we know the habits of that particular worm, than simply to say that the person is a "parasite." People respond well to those who can speak using analogies. Analogical-talking is an example, I think, of one of the highest orders of intelligence. It encourages creative thinking in one's listeners and it presents learning as a visual discipline.

Looking at the Phyla

In trying to come up with this study plan, then, I decided that I would go to the most all-inclusive category of living things that makes sense to study. There are about 35 phyla (38 in this Wikipedia list) of creatures in the animal kingdom. What I plan to do in these pages is to give you at least 2 essays/phyla on average so that we not only learn how to categorize these creatures but that we also learn new words, categories of thought and pictures that will help us understand ourselves and life more deeply. Rather than going alphabetically through the phyla, I will pick and choose according to my mood and my own learning instincts. But I hope to probe many of them. I currently seem to be fascinated with worms, and especialy parasites, so I begin with the Nematomorpha (lit. "thread form") in the next essay. I will link it to a most interesting video clip, so I hope you will join me.

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