Classification of Organisms Section 1: Categories of Biological Classification Section 2: How Biologists Classify Organisms
Categories of Biological Classification Objectives:
Describe Linnaeus's role in developing the modern system of naming organisms.
Summarize the scientific system for naming a species.
List the seven levels of biological classification.
Categories of Biological Classification Taxonomy
A Simpler System Swedish biologist Carl Linnaeus developed binomial nomenclature, the two-word system of naming organisms.
Scientific Names Scientific names are written in Latin and give biologists a common way of communicating, regardless of the language they speak. The scientific name of an organism consists of its genus name followed by a second name, which identifies its species.
Scientific Name Rules:
Genus name capitalized 3. Underlined (or italic)
2 nd name lower case
Each group will be given a list of 6 related organisms.
Using the internet, determine the scientific name of each organism and write in your paper
Find a detailed picture of each organism. Type their common and scientific name after the picture
Print off one copy for each group member.
Sample Dichotomous Key
1a.Bean round Garbanzo bean
1b.Bean elliptical or oblong Go to 2
2a.Bean white White northern
2b.Bean has dark pigments Go to 3
3a.Bean evenly pigmented Go to 4
3b.Bean pigments mottled Pinto bean
4a.Bean black Black bean
4b.Bean reddish-brown Kidney bean
Dichotomous Key Rules of Thumb
Start with the most general characteristics and progress to increasingly more specific characteristics.
Indent each couplet or leave a space between each couplet to make the key easier to read.
Use measurements when possible, avoiding descriptors like large or small if possible.
Use characteristics that are found year-round, not seasonal if at all possible (sometimes the point of a key is identifying organisms based on seasonal characteristics, such as flowers). If your key is seasonal, indicate it in the title of the key.
Start the choices in the pair with the same word , if possible.
Dichotomous Key Assignment
Find high quality pictures of your organisms online (Google-images) and cut and paste them into a word document. Place the organisms scientific name and common name underneath
Design a dichotomous key that corresponds to the organisms.
Dichotomous Classification Key
Has a key which presents the user with two opposite categories about a trait.
This leads the user to further pairs of statements.
By going from one set of statements to another its classification group is determined.
Categories of Biological Classification Classifying Organisms
Categories of Classification The modern system of classification includes the following eight groups: domain, kingdom, phylum, class, order, family, genus, and species.
Section 1 Categories of Biological Classification
Classification of the Honeybee Each category of classification is based on characteristics that are shared by all the organisms in the category. The European honeybee is classified as: Eukarya, Animalia, Arthropoda, Insecta, Hymenoptera, Apidae, Apis , and mellifera .
How Biologists Classify Organisms Objectives:
List the characteristics that biologists use to classify organisms.
Summarize the biological species concept.
Relate analagous structures to convergent evolution.
Describe how biologists use cladograms to determine evolutionary histories.
How Biologists Classify Organisms What is a Species?
Species Species were traditionally defined according to their appearance and structure.
Biological Species The biological species concept defines species according to their sexual reproductive potential.
How Biologists Classify Organisms What is a Species? continued
Evaluating the Biological Species Concept The biological species concept cannot be used to classify asexually reproducing species.
Number of Species The number of the species in the world is much greater than the number described.
How Biologists Classify Organisms History
Cladistics Cladistics focuses on sets of unique or derived characteristics found in a particular group of organisms to reconstruct an evolutionary history.