Essay/Term paper: Scientific classification

Essay, term paper, research paper:  College Papers

Classification is grouping together similar things. It is something that
you have done in your daily life since you were a child. There are many
different ways to classify organisms. There are aquatic and terrestrial
animals. Certain plants can be grouped together as either trees or shrubs
according to their outward appearance. Using these methods is useful for
some purposes. Generally it is more useful to classify organisms in
accordance with their relationships with one another. More to the point
the systems discussed today are the ones used universally and based upon
Carolus Linnaeus' original work. Carolus Linnaeus is probably the single
most dominant figure in systematic classification. Born in 1707, he had a
mind that was orderly to the extreme. People sent him plants from all over
the world, and he would devise a way to relate them. At the age of
thirty-two he was the author of fourteen botanical works. His two most
famous were Genera Plantarum, developing an artificial sexual system, and
Species Plantarum, a famous work where he named and classified every plant
known to him, and for the first time gave each plant a binomial. This
binomial system was a vast improvement over some of the old descriptive
names for plants used formerly. Before Linnaeus, Catnip was known as:
"Nepeta floribus interrupte spicatis pedunculatis" which is a brief
description of the plant. Linnaeus named it Nepeta cataria--cataria
meaning, "pertaining to cats". The binomial nomenclature is not only more
precise and standardized; it also relates plants together, thus adding
much interest and information in the name. For instance, Solanum relates
the potato, the tomato and the Nightshade.

Binomial Classification Early on in naming species taxonomists realized
that there would have to be a universal system of nomenclature. Why? For
example, it would seem to be a lot less complicated to just give a species
a vernacular name that is easy to pronounce. Let's look at the loon of the
North American lakes for example. In English it is called the common loon
in North America. Seems simple enough, but in England it is called the
great northern diver. In French it is plongeon imbrin, in France, and in
Quebec le huart a collier. In Spanish it is called somorguajo comun, Islom
in Swedish, and Eistaucher in German. So you see how much time and calling
the species Gavia immer can save confusion. Binomial classification in its
simplest form is a way of naming a species by means of two names both in
Latin. (binomial nomenclature) It was first introduced by Carolus
Linnaeus. In Binomial classification the first name, which begins with a
capital letter is known as the Genus it is always capitalized. The genus
is a group of species more closely related to one another than any other
group of species. The genus is more inclusive than the species because it
often contains many species. The second part of the binomial represents
the species itself and is always printed with all letters in lower case. A
species is a group of individuals that are alike in many different ways.
Individuals are in the same species if they are: 1. Are able to mate with
those similar to themselves. 2. Produce young that are themselves able to
reproduce.

As an example, in the cat family, the genus Panthera is coupled with the
species leo to form Panthera leo, the Lion. Likewise, Panthera is coupled
with tigris, to form Panthera tigris the Tiger. In simplified terns both
the Lion and Tiger share common traits and a common genus - Panthera,
whilst clearly remaining separate species.

Closely related species are a genus, closely related genera (plural form
of genus) are grouped together in a family. Closely related families are
grouped into an order, and so on, into more inclusive categories, or
levels in the classification hierarchy. Taxonomic Hierarchy Approximately
one and a half million species have been classified and there are
estimates that over five million species remain to be discovered. For
biologists to order this mass of information, a scientific system called
taxonomy was introduced. The basic idea is to group species with similar
characteristics together into families, and to group the families together
into broader groupings. To this end, the taxonomic categories where
devised, and they create the taxonomic hierarchy. The hierarchy goes (with
an example):

*Categories Example
Kingdom Animalia
Phylum (Plural = Phyla) Cordata *In plants, this category is
often called a division* Class Mammalia

Order Carnivora
Family Canidae
Genus Canis
Species Lupus (the Wolf) * Kim Puts Candy Out For Good
Students*

Every species is in only one genus. Similarly, every genus is in only one
family, and so forth up the hierarchy. The most inclusive category for
classifying groups of similar organisms is the kingdom. It is argued
exactly how many Kingdoms there are though. Up until recently, only two
kingdoms were generally used, the plant and animal kingdoms. Now however
there are 5 established kingdoms and one controversial unofficial kingdom.


The 5 kingdoms:
1. Kingdom Animalia (The Animal Kingdom)
ex: Multi-cellular motile organisms, which feed heterotrophically
(Humans)
2. Kingdom Plantae (The Plant Kingdom)
ex: Multi-cellular organisms, which feed by photosynthesis (Tulips)
3. Kingdom Protista (The Protist Kingdom)
ex: Protozoa and single-celled algae
4. Kingdom Fungi (The Fungus Kingdom)
ex: Yeast
5. Kingdom Monera (The Monera Kingdom)
ex: Bacteria and blue-green algae

Parallel to these Kingdoms, but not included, are the Viruses. These are
acellular entities with many of the properties of other life forms, but
are genetically and structurally too dissimilar to the species
categorized above to fit into that scheme of taxonomy.