Chapter 17: Organizing Life’s Diversity
Pages 482 - 511
Section 1
The History of Classification
Main Idea: Biologists use a system of classification to organize information about the
diversity of living things.
Vocabulary
1. Classification – is the grouping of objects or organisms based on a set of criteria
2. Taxonomy – is a discipline of biology primarily concerned with identifying, naming, and
classifying species based on natural relationships
3. Binomial nomenclature – gives each species a scientific name that has two parts (genus
and specific epithet)
4. Taxon – a named group of organisms, such as a phylum, genus, or species
5. Genus – a taxonomic group of closely related species with a common ancestor
6. Family – taxonomic group of similar, related genera that is smaller than a genus and
larger than an order
7. Order 8. Class 9. Phylum 10. Division 11. Kingdom 12. Domain -
Early Systems of Classification

Aristotle’s System – He divided living things into one of two broad categories: with
blood or without blood. Then he furthered that by how the organism moved – did it fly?
Did it crawl? Did it walk? Did it swim? This was simple and was a good starting point,
but it had its limitations which were:

Linnaeus’ System

Binomial Nomenclature – Linnaeus came up with this. It gives each species a scientific
name that has two parts. The first part is the genus and the second part is the specific
epithet, or scientific name, that identifies the species. Latin is the base of this system
because Latin is an unchanging language. We call it a dead language. The red cardinal is
used as an example. We may call it a red bird, a cardinal, or flappy bird as a common
name that changes depending on what part of the country we are in; however, the
scientific name never changes and it can be used as a universal classification by scientists
or anyone who bothers to learn the Latin name: Cardinalis cardinalis.

Modern Classification Systems
Taxonomic Categories

Species and Genus

Family

Higher Taxa
Systematics Applications
Section 2
Modern Classification
Main Idea: Classification systems have changed over time as information has increased.
Vocabulary
1. Phylogeny 2. Character -
3. Molecular clock 4. Cladistics –
5. Cladogram – diagram with
branches that represents the
hypothesized phylogeny or
evolution of a species or group;
uses bioinformatics, morphological
studies, and information from
DNA studies. To the left is an
example of how it is hypothesized
our modern “killer whales”
evolved.
http://www.popscicoll.org/whaleevolution/cladogram.png
6.
Determining Species

Typological Species Concept

Biological Species Concept

Phylogenetic Species Concept
Characters

Morphological Characters

Biochemical Characters
Phylogenetic Reconstruction

Cladograms

The Tree of Life
Section 3
Domains and Kingdoms
Main Idea: The most widely used biological classification system has six kingdoms
within three domains.
Vocabulary
1. Eubacteria
2. Archaea
3. Protist –eukaryotic organisms can be unicellular, colonial, or multicellular; they do not
have organs. They are not necessarily grouped together because they are similar to each
other, but because they are too different from anything else to be grouped into any other
group. By default, they are put together. The plant-like protists are called algae (ex.
Kelp); they perform photosynthesis. The animal-like protists are called protozoans (ex.
amoebas). The fungus-like protists are your slime molds and mildews. Then there is the
euglenoids that have both plant-like and animal-like characteristics.
4. Fungus
Grouping Species
a. The broadest category in the classification system is the domain
b. There are three domains: bacteria, archaea, and eukarya.
c. Within these three domains are six kingdoms: bacteria, archaea, protists, fungi, plantae,
and Animalia.
d. Organisms are classified into domains according to cell type and structure; and into
kingdoms according to cell type, structure, and nutrition.
e. This system has been in use for only about two decades (book published in 2008)
f. The reason the system was changed was because scientists discovered an entirely new
kind of organism in the 1970’s. These new organisms were unicellular prokaryotes that
were named archaebacteria. Since they were nothing like the other known bacteria, they
were renamed in 1990 and given their own domain of Archaea.
Domain Bacteria
Domain Archaea
Domain Eukarya

Kingdom Protista

Kingdom Fungi

Kingdom Plantae

Kingdom Animalia

Viruses – an exception
Example of a taxonomic chart for Panthera pardus, aka Leopard
https://www.google.com/search?q=classification+chart&safe=active&rlz=1T4MXGB_enUS532US532&source=lnms&tbm=isch&sa=
X&ei=pk5iU6KaKsPE8QHxtIC4Bw&sqi=2&ved=0CAYQ_AUoAQ&biw=1280&bih=820#q=taxonomic+chart+domain&safe=activ
e&tbm=isch&facrc=_&imgdii=_&imgrc=YGXTbKBsjSSfQM%253A%3BvazUTZi9pj1WYM%3Bhttps%253A%252F%252Ffacinat
ingamazinganimals.files.wordpress.com%252F2012%252F03%252Flevels_of_classification.jpg%3Bhttp%253A%252F%252Fwww.
ummah.com%252Fforum%252Fshowthread.php%253F357367-Your-guide-to-quot-Evolution-quot-amp-quot-Darwinismquot%3B638%3B700
http://www.scholarsjunction.com/project-images/bio/Taxonomy.gif
http://imr.jenniferakkermans.com/wp-content/uploads/2011/05/taxonomy-chart1.jpg