TAXONOMY AND SCIENTIFIC TRENDS

Scientific names often seem threatening to most people. It is often asked why use names based upon Latin and Greek when no one speaks those languages anyway? In the early history of science scholars had to decide upon a common language for the communication of technical information. Since the classical forms of both languages were relatively stable and unchanging it was decided to use them as a standard. In addition many early scholars were churchmen and Latin was the formal language of the Church. Thus scientific names are written as they are. In most instances the names are either descriptive or they name an organism in honor of a person known to the scientific community or after a figure from mythology.

It was the great Greek philosopher and biologist Aristotle that first attempted a serious classification of living organisms on the basis of structural similarities. The science of classification is called taxonomy and the science which deals with evolutionary relationships is termed systematics. Both fields support each other in their attempts to understand the development of life on Earth.

It should be remembered that prior to Carolus Linnaeus (1707 - 1778) that all organisms were named in either short Latin or Greek paragraphs. It was Linnaeus, who was a Swedish botanist at the University of Upsula, with his publication of SYSTEMA NATURAE in 1758 that did the scientific literature as well as persons interested in the study of living things a great favor with the development of the system that has become known as "Binomial Nomenclature". In this system each living species is given two names, genus and species.

As a point of interest, the concept of what constitutes a species has often been the subject of heated debate. The most classic definition is a population of similar organisms which freely interbreed and which produce fertile offspring. This is still a widely held idea but it does not take into account the concept of the A cline. A cline can best be thought of as a population of a species which is disrupted by some phenomenon such as geological features. The disrupted populations along the length of the cline can interbreed producing offspring which fulfill the classic definition, but those at the extreme ends sometimes can not. In short the terminal groups through time have had alterations occur in their gene pools such as to isolate them from the average of the over all population. With this concept, a reality which is now well understood, the definition has been modified to read: A species is a population of similar organisms which freely interbreed. Even this idea is open to serious debate. There are those that indicate, and I might add with strong supporting evidence, that the concept of species as we would care to think of them simply does not exist in nature.

Gene pool alteration occurs in several ways. The first and most dramatic is mutation. Mutations generally occur in two ways. There are what we term spontaneous mutations and those which we call Ainduced mutations.Spontaneous mutations are rare yet occur with some regularly in the DNA of cells. If these occur in normal body cells they have little effect except on the cell in question. If however they occur in gametes (sex cells) and these cells happen to be the ones used in the production of an offspring then that offspring will bear what ever the effect of the mutation has produced. If the organism lives then the pressures which Charles Darwin termed Natural Selection have an impact on it for better or worse. If the changes produced were positive and provided the individual with some survival advantage then it lives to procreate and the mutation is passed on. If the mutation were in any way disadvantageous then it is eliminated.

This elimination may come in many ways. Some of the most common are an inability to adapt to predation, the introduction of new disease, and climatic fluctuations.

Induced mutations occur as a result of agents in the environment which have the power to alter the structure of DNA. In the early history of earth one of the major such agents was the impact of ultra violet light coming in through an atmosphere with little ozone to block it out.

Gene pool alterations may also occur as a result of similar organisms not of the same population migrating in and interbreeding with the primary group. When this occurs the introduced genetic material becomes incorporated and slowly the original population is changed.

One of the most fascinating aspects of insect evolution especially that of the lepidoptera is related to the development of the flowering plants. These plants are known as angiosperms. During the 150 + million year reign of the dinosaurs the dominant plant species were the gymnosperms. The name literally means Anaked seed. Such plants are the conifers of today like the pines etc.. Of the several theories put forward to explain the demise of the dinosaurs the advent of flowering plants is one of the most interesting. It is known that many of the larger herbivorous dinosaurs fed on gymnosperms. They were of course the prey of the large carnivores. As the angiosperms displaced the food of the herbivorous species their numbers dropped. We are aware now that at this same period there were migrations from one land mass to another. When ever there are migrations there follow diseases and with limited or no resistance animals die. It was about this same time that the asteroid strike of 65 million years ago occurred. The earth was impacted by and asteroid about six miles across. It came down in the area of what is now the Yucatan in Mexico. The impact was so intense that it is thought to have generated firestorms around the entire planet ending in what can only be likened to the idea of a nuclear winter. It is thought that the resulting cloud cover may have lasted for many years. Such upheaval completely altered the face of the planet and provided the opportunity for massive evolutionary changes to take place. Mammals for example that had been living at the feet of the dinosaurs now had a chance to develop more fully. We are most likely the end of one of those chains of evolutionary processes.

The angiosperms which survived along with the many insect forms developed strong interdependent relationships. Insects developed eyes which could see the infrared spectrum. A fact that plants capitalized on in attracting insect friends as pollinators. May species became so dependent upon each other that the loss of one would spell the doom of the other. A classic example is seen in the pollination dependency of certain species of yucca plants and moths of the genus Pronuba. In return the sole larval food sources of these moths are the very plants which they pollinate. Quite literally uncountable thousands of such relationships developed helping both the plants and the insects in their survival efforts. The butterflies and moths are major pollinator species.

Going back to the concept of taxonomy and the efforts of Linnaeus, when we see a scientific name: Anteos maerula Fabricius, 1775. Anteos is the genus name, maerula is the species name, Fabricius is the scientist that first described the species, and 1775 is the year that his description was first published.

In some instances there are more than just two names applied to a species. In this instance the third name is either a subspecies or infrasubspecific form. An example would be: Morpho peleides Kollar, 1850, subspecies micropthalmus Fruhstorfer.

It should also be noted that scientific names if in print are always correctly placed in italics. Genus names are always capitalized and species names are always in lower case letters. Common names, though seemingly more user friendly, create many problems. The major reason is that from region to region there is often more than one common name for the same organism. There is no standardization in this system.

Thus living organisms are assigned to a KINGDOM which is broken down into PHYLUM, which is broken down into CLASS which is broken down into ORDER, which is broken down into FAMILY, which is broken down into GENUS into which individual SPECIES are placed. Individual species then may be subdivided into SUBSPECIES = GEOGRAPHIC RACE and further if needed into INFRASUBSPECIFIC FORM.

Kingdoms, Phylums, Classes, Orders, and Families my be further designated into slightly larger or smaller groups by the prefix: Super or Sub (Example: SUPERPHYLUM or SUBPHYLUM). In addition Genera may also be grouped into larger categories called TRIBES.

The science of naming living organisms is called TAXONOMY and it is always based upon the science of SYSTEMATICS (Evolution of organisms). Today the whole business is supported by studies in Paleontology, Embryology, and Anatomy and Physiology.