Mr. T's Science Scene

Classification and Taxonomy

Classification of living things was born out of necessity!  In the early and mid 1800s a man by the name of Carl Von Linne was growing up a farmer in Southern Sweden.  At the age of 16 or so he entered university to become a doctor and soon after switched to the University of Upsalla in order to study botany.  He would spend the rest of his life there; first as a student and then as a professor of Botany.

This, however, is not why classification came about.  As Carl and his friend Petris were attending Upsalla, they discovered that animals and plants were named through the use of common names that only a select few in a select circle would know.  It was frequently the case that a person with a specimen on one side of the campus would be using a different name than a peson with the same specimen on the other side of the campus!  There was no organization as to how things were being named.  

This, by itself, wasn't a big deal until you factored in any learning derived from those collections; learning such as what was harmful and what was not, what was a new species and what wasn't, what medical disease you had and whether or not there was a cure or medicine for it.

So, Carl- who was now known as Carlus Linneus- and Petris starting documenting plants and animals establishing two names- binomial nomenclature or their scientific names- using latin and greek.  Along with those names were hand drawn pictures and elaborate descriptions of the plant or animal.  Essentially, the two of them took every living thing they came across and divided them into two kindgoms- Plants (Planta) or Animal (Animalia) and then name them with a Genus and a species.

These books eventually went to print (because SO MANY people were using them) as the Systema Naturea or Nature Systems and thus began the Classification System used around the world today.  So, no matter what language you speak, anyone, anywhere can accurately classify the life around them (and learn, discuss, discover things about life) in a common language (Latin or Greek).

The system, TODAY, looks like this:

Kingdom:  Very broadly related (Blue whale and an ant)          Human:  Animal

Phylum:  More related  (Blue whale and a lizard)                     Human:  Vertebrate

Class:  More related  (Blue whale and a mouse)                       Human:  Mammals

Order:  More related  (Moose and deer)                                    Human:  Primate

Family:  More related  (Australopithecus and Humans)             Human:  Hominidae

Genus:  More related  (Horse and Donkey)                                Human:  Homo

specis:  As related as you can get  (gray squirrel)                      Human:  Homo sapiens sapiens

A silly sentence to remember the order is "King Phillip Came Over From Greece Saturday".  While there were only two kindgoms back then, we now have 5 (6) kingdoms:  Animals, Plants, Fungus, Protists (single celled organisms WITH a nucleus), and Monera (disease; bacteria and viruses- signle celled NO nucleus).  In some cases, Monera is divided into Eubacteria (common) and Archaebacteria (uncommon, ancient).

As you move from Kingdom to species, the number of different organisms within the category decreases!


Taxonomy, Classifiation, Identification, Dichotomous, and Biologicial key are all terms that mean the same thing:  A device used to isolate a specific thing so that you can name or classify it.  There are many examples of these keys- many are found in identification books, there are keys at stores like Home Depot and Lowes to help you find the correct bolt or nut, automotive stores have keys to help you find the correct air filter, oil filter, or oil.  Search engines are taxonomic keys- especially when you are trying to buy something and use the key to narrow down your selection!

The keys you will be working with are pretty simple and consist of a series of "yes" and "no" questions found in pairs.  These questions (and the answer you assign it) lead to a name or a direction.  An example is as follows.


1. A  It has a hard shell . . . . . . . go to 2

    B.  It does not have a hard shell . . . . . go to 3


2.  A  It can be found in fresh water in Penfield . . . . . painted turtle

    B.  It is found in the oceans bordering NY . . .  crab


3.  A  It is very flexible with dry scales . . .  corn snake

     B.  It has 8 legs and hairs . . . . .  tarantula


Now, hopefully, you are thinking a) this is terribly simple- and it is though most keys are MUCH longer and b) yea, but there's a lot of things without a hard shell or more things than a turtle and crab have shells.  And you'd be right.  Which leads us to our next point- a key is only good for the population of things that it has been written for!  My Eastern bird books will not have the California Condor in it.  My spider book will not have insects in it.  A search on a clothing stores web site will not come up with power drills.  And so on. . . .


Next

Previous

Home Unit