a magazine focused on scientific achievements of the past
The Significant Seven: Carolus Linnaeus and Taxonomy
(Each month this
feature will highlight seven significant facts about a selected topic)
So you think you know a little bit about taxonomy, huh? Well, if I have just called to mind a large moose head hanging on an avid hunter's library wall, you're reading the wrong magazine! This month's Significant Seven is dedicated to Carolus Linnaeus and the scientific system of classification. All things can be arranged in a hierarchial system, but in this issue our focus is on living organisms. Carolus Linnaeus is often referred to as the "father of taxonomy" and therefore many of us are familiar with him and his system of organismal classification. But we think we dug up a few facts that maybe you didn't know about this legend and his most famous work. Well, make that six facts; we thought you might enjoy a simple review of the current classification kingdoms!
Fact #1. We've all heard of Carolus Linnaeus and his system of binomial nomenclature. But did you know that Linnaeus was not the originator of this idea? A two-word naming system of classification originated in the 15th century and was used throughout the 17th century by Herbalists such as Otto Brunfels, Leonhart Fuchs, and Gasbard Bauhin. Linnaeus' system refined and popularized what these men had already been practicing and was additionally influenced by the work of Conrad Gessner, who had made the disctinction between genus and species and order and class when classifying plants.
Fact #2. One of the first systems of biological classification named and grouped around 1500 plants based on their growth habit of either tree, shrub, or herb. Do you know who first approached classification in this manner? You guessed it, none other than the subject of this month's featured interview, Aristotle! Aristotle also had a similar system for classifying animals in which he grouped them according to how they moved; by land, air or water. Where do you think an alligator or duck would fit in this system?
Fact #3. There are five main systems of classification that have been in use over the last 2000 years. They are listed below by their type, how they were determined and who primarily used them.
A. Utilitarian: Classified by the use of the plant / Dioscorides
B. Form: Classified by habit of the plant / Theophrastis
C. Artificial: Classified by a few obvious characteristics / Carolus Linnaeus
D. Natural: Classified by overall resemblances / John Ray
E. Phylogenetic: Classified by evolutionary characteristics / Robert Thorne, Arthur Cronquist, Armen Takhtajan, and Rolf Dahlgren
Fact #4. Many science buffs are aware that binomial nomenclature is the two-part naming of organisms; binomial meaning "two name" and nomenclature meaning "system of naming". This naming system consists of the genus and species of the organism and is written in the Latin form. But did you know that Carolus Linnaeus is actually the two-part Latin version of his real Swedish name? Linnaeus' name before he converted it was Carl von Linné.
Fact #5. Linnaeus' system is actually what's called an artificial system because it relied on observations of so few features of plants, mainly the reproductive parts. His system did not take all the characteristics of an organism into consideration and therefore many unrelated plants, such as cherries and cacti, were grouped together because of one common feature. Linnaeus predicted that this would change long after his lifetime when scientists learned more about plants and animals and could create a more accurate system of natural classification. Natural taxonomy, in which the overall characteristics of organisms are considered when grouping them together, was first realized in the 17th century in the work of a botanist named John Ray. Although systems today are based largely on Linnaeus' method, they reflect an evolutionary relationship between organisms, founded from Charles Darwin's ideas, and are therefore termed phylogenetic.
Fact #6. During Linnaeus' time, there were only two kingdoms; Animalia and Plantae. In 1969 American biologist R. H. Whittaker suggested that all living things could be divided into five kingdoms. Although this five kingdom system is what is commonly used today, some scientists argue for a sixth kingdom or even more. As the study of genetics becomes more advanced, scientists are better able to distinguish details among organisms and therefore argue that these differences warrant a further separation of classification.
Fact #7. Well, here's that refresher we promised you! The final fact is a simple summary of today's five primary kingdoms and how organisms are separated into them.
| Kingdom (examples) |
Nucleus |
Cellular Property |
Modes of Nutrition |
| Kingdom Monera (bacteria,
archeabacteria) |
Prokaryotes (no nucleus) |
Unicellular |
Absorbtion (some photosynthesis) |
| Kingdom Protista (protozoans,
algea) |
Eukaryotes (true nucleus) |
Unicellular |
All Modes of Nutrition |
| Kingdom Plantae (plants) |
Eukaryotes | Multicellular | Photosynthesis (some absorbtion) |
| Kingdom Fungi (mushrooms, smuts) |
Eukaryotes | Multicellular | Absorbtion |
| Kindom Animalia (animals) |
Eukaryotes | Multicellular |
Ingestion |
Bibliography:
Picture- Carolus Linaeus, http://en.wikipedia.org/wiki/Carolus_Linnaeus
Sources- "Taxonomy", Wikipedia, http://en.wikipedia.org/wiki/Taxonomy
"Scientific Classification", Wikipedia, http://en.wikipedia.org/wiki/Scientific_classification
"Carolus Linaeus", WordiQ, http://www.wordiq.com/definition/Carolus_Linnaeus
Randy Moore, W. Dennis Clark, Darrell S. Vodopich, "Botany" second addition, pp. 573-581