1. TAXONOMY

2. TAXONOMY NOTES, PT. 1

3. TAXONOMY
Taxonomy = the science of grouping organisms on the basis of their similarities
First taxonomic systems proposed by Greek philosopher Aristotle around 350 B.C.
He divided living things into two groups:
Animals &
Plants
He subdivided plants & animals on the basis of their size and structure
Ex. Herbs, shrubs & trees were three major divisions of plants

4. TAXONOMY Aristotle’s system was used for more than 2000 years
During the mid-1700’s, biologists set out to discover previously unknown forms of life
As a result, thousands of newly discovered organisms were discovered yearly
Using Aristotle’s system, biologists found it did not sufficiently describe the relationships between two organisms
Ex. two species of cat with very different habitats and behavior would be forced into different groups

5. TAXONOMY System used to name these new organisms greatly varied
This made communication between biologists very difficult
Swedish botanist named Carolus Linnaeus developed new classification system
He suggested that organisms with similar structures should be placed in the same taxonomic group and this group should be called a species

6. TAXONOMY
Species = A biological group whose members resemble one another and interbreed to produce fertile offspring
He suggested that similar species be grouped into a larger category called genus
Ex. dogs, wolves and jackals are different species but are similar enough to be considered members of the same genus

7. COMMON NAME Most organisms are known by their common name
Very confusing because one animal may end up with many names
Ex. Mountain lion also known as puma, cougar, catamount or panther

8. COMMON NAME Two organisms may end up with the same name
Ex. Dolphin (the bony fish, found in restaurants OR the mammal that people see at Sea World)
Animals common names may be misleading
Ex. starfish, silverfish and jellyfish are all very different and none of them are fish

9. SCIENTIFIC NAME To avoid such problems, the scientific name is used
Scientific name is accepted by all scientists
Linnaeus suggested that an organism’s scientific name be its genus name followed by its species name
Known as binomial nomenclature (bi = two, nom = name) (nomenclature = system of naming things)
Western lowland gorilla scientific name = Gorilla gorilla gorilla

10. SCIENTIFIC NAME Written in Latin in a very specific way
Genus name begins with a capital letter
Species name begins with a lower case letter
Written in italics if typed or underlined if handwritten

11. SCIENTIFIC NAME Many scientific names are descriptive
The red maple is Acer rubrum = red maple in Latin
Sometimes scientists name organisms after a scientist he/she admires
Genus Linnea, an herb in cold areas, named in honor of Linneaus
Red maple = Acer rubrum
Linnea borealis

12. SCIENTIFIC NAME
Sometimes species names describe where an organism lives
Darlingtonia californica = carnivorous cobra lily of California

13. TAXONOMY NOTES, PT. 2

14. TAXONOMY
Theory of evolution has, since 1753, influenced classification
Modern taxonomy still utilizes structural similarity as a basis but they also use chromosome structure, reproductive potential, biochemical similarities, and embryology to determine classification

15. CHROMOSOMAL MAKE-UP
Scientists believed for a long time that humans were more closely related to gorillas than to chimpanzees based on our structures but found, when looking at chromosomes, that we are much more closely related to chimps than to gorillas.

16. REPRODUCTIVE POTENTIAL
Scientists will cross closely related plants to see which ones will produce fertile offspring. Those that do are considered to be in the same species.
Ex. Donkey + horse = mule (which is infertile )
Shows that they are NOT the same species

17. BIOCHEMICAL MAKE-UP
Horseshoe crab was classified by its external appearance. When blood proteins were examined, it was found that these so-called crabs were more closely related to spiders. They have since been reclassified.

18. EMBRYOLOGY
Scientists can look at the wing of a bat and the flipper of a whale and determine that they came from the same embryonic tissue and initially develop in the same manner. Meaning, bats and whales had a common ancestor and bats are more closely related to whales than they are to birds.

19. CLASSIFICATION Categories of classification—Largest to the smallest
Kingdom (Kings)
Phylum (Play)
Class (Chess)
Order (On)
Family (Fancy)
Genus (Girls)
Species (Shoes)

20. CLASSIFICATION Ex. Humans Kingdom Animalia Phylum Chordata
Class Mammalia
Order Primates
Family Hominidae
Genus Homo
Species sapiens
Order Primates
Kingdom Animalia
Family Hominidae

21. CLASSIFICATION Ex. Killer whale Kingdom Animalia Phylum Chordata
Class Mammalia
Order Cetacea
Family Delphinidae
Genus Orcinus
Species orca
Class Mammalia
Kingdom Animalia
Order Cetacea
Family Delphinidae

22. CLASSIFICATION Ex. Tiger Kingdom Animalia Phylum Chordata
Class Mammalia
Order Carnivora
Family Felidae
Genus Panthera
Species tigris
Ex. Lion
Kingdom Animalia
Phylum Chordata
Class Mammalia
Order Carnivora
Family Felidae
Genus Panthera
Species leo

23. CLASSIFICATION Siberian Tiger Family Felidae Order Carnivora
Female Lion

24. FIVE KINGDOMS Animalia = all multicellular animals
Plantae = all multicellular plants
Protista = most unicellular organisms
Monera = cyanobacteria, bacteria, other organisms that lack nuclei
Fungi = all fungi

25. MAJOR PHYLA Porifera—the sponges
Colenterata/Cnidaria—Jellyfish, coral, anemones

26. MAJOR PHYLA
Platyhelminthes—flat worms
Nematoda—round worms

27. MAJOR PHYLA Annelida—segmented worms
Mollusca—oysters, clams, octopus, squid

28. MAJOR PHYLA Arthropoda—insects, crabs, lobsters, shrimp
Echinodermata—sea stars, sand dollars, sea urchins

29. MAJOR PHYLA
Chordata—Birds, fish, mammals, reptiles, amphibians