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Have you ever thought about why we name
things at all? If you have you probably realized that names
are very important for identifying things, especially when communicating
with other people. However not everybody uses the same name for
the same animal. For instance slaters, cheesybugs and woodlice are all
different names for the same animal in different parts of the world.
These are known as common names.
They can vary so much that in the 1750's
scientist Carl Linnaeus suggested a method of naming things that could
be used by scientists all over the world. He introduced binomial
nomenclature, which means two names. Both were in Latin. The
first name identifies the genus and the second the species, such as Homo
sapien. Such names follow a specific format. Because the
names are Latin, they often appears in italics. Only the first
name is capitalized. The science of naming things is called
taxonomy and though it can become quite complicated the basics are easy
to understand.
All the living things are divided into a series of
sets and subsets depending on how closely related they are.
Kingdoms
All living things are
first divided into 5 kingdoms Plants, Animals, Fungi,
very small things called Protoctista, and even smaller things called
Bacteria. These last two are so small you can't see them
without a microscope.
Phylum
All organisms within a kingdom are then divided into groups based on
common characteristics. The living members of the kingdom Animalia
are divided into approximately 36 smaller groups called phyla
singular phylum. One of the phylum is the Arthropoda.
It contains animals that have external skeletons.
Class
Phylum is a very broad classification and is then broken down into
smaller units called Classes. Arthropoda contain the following
classes:
Crustacea - These include the Lobsters, Crabs and Woodlice
Myriapoda - The Centipedes and Millipedes.
The Chelicerata (Arachnida) - Spiders and Scorpions
Uniramia (Insecta) - the true insects, such as bettles, bees, and
butterflies.
Trilobita - These are extinct animals.
Orders
The next subdivision is orders. The uniramia or insecta are divided into 29
even smaller, though still pretty large groups called orders.
For a description of the orders,
Cllick Here.
Families
Orders are then divided into families.
For example, within
the order Lepidoptera (the butterflies) there are about 90 families; within each family
are a number of genera and within each genus are a number of species.
You should note that most animals and plants are
known only by their genus and species names, i.e. the small
tortoiseshell is Aglais urticae, note also that while the genus
name is spelt with a capital letter the species name is normally spelt
with a small letter, and that in printed text the pair are normally
written in italics the rest usually remains unsaid. You should
also note that though an animal will generally share its genus, family,
order and class names etc. with other animals its combination
genus/species name will be unique to it. In some books you may find a
persons name or part of a persons name written after the animals name
i.e. Formica exsecta Nyl., Nyl stands for Nylander the person who
first described and named the species for science, if this name is in
brackets it means that although he described the species first he got
the genus wrong, and it has since been moved to a different genus.
Finally you should know that scientist are still arguing about some of
the family, class and order names so these may be different in different
books, but until you get to university this is not very important.
Note also that identifying, describing and
naming things, i.e. assigning them to particular groups is taxonomy,
while arranging those groups in a coherent order which reflects their
evolution and relatedness is classification. Another word is Systematics
which may be defined as the study of the diversity of organisms and the
way they relate to each other, modern Systematics is called Phylogenetic
Cladistics and has a whole set of special rules telling you how to do it
properly. Cladistics is a good, but young science and like all tools its
usefulness reflects the understanding in the mind of the person using
it, i.e. not all the results that people using cladistic analyses come
to are equally reliable.
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