Chapter 20Classification

Binomial Nomenclature

Basic group used for identifying organisms is the species.

Carolus Linneaus began giving every species its own unique binomial (two word) name.

The first word was the genus, the second word was the species.

Example: Homo sapiens -- Homo = genus, sapiens =species

Taxonomy Taxonomy – the branch of

biology concerned with the classifications of organisms.

Organisms are classified in a hierarchy of larger and more inclusive categories.

Most Inclusive Kingdom Phylum Class Order Family Genus

Least Inclusive SpeciesKings Play Cards On Fat Green Stools

Taxon – a group of organisms defined by the classification scheme.

Example: class, species

Five Kingdoms Prokaryotae Protista Fungi Plantae Animalia

Dichotomous Key A way of determining the

identity of an organism.

It is a list of questions that are answered yes or no.

The answer tells you which question to go to.

Our specimen: long stem, large green leaves, pink flowers, small brown thorns.

1. a. specimen has a long stem – go to 3 b. specimen does not have long stem – go to 2

2. a. specimen has large orange flowers – go to 6. b. specimen has no large orange flowers – go to

8.

3. a. specimen has large green leaves – go to 4. b. specimen does not have large green leaves–go

to 9.

4. a. specimen has pink flowers – go to 5 b. specimen has no pink flowers – go to 7

5. a. specimen has brown thorns – Rosaciea carnicovia

b. specimen has no brown thorns – go to 10

1. Leaves usually without teeth or lobes: 2 1. Leaves usually with teeth or lobes: 5

2. Leaves evergreen: 3 2. Leaves not evergreen: 4

3. Mature plant a large tree — Southern live oak Quercus virginiana

3. Mature plant a small shrub — Quercus minima

4. Leaf narrow, about 4-6 times as long as broad — Willow oak Quercus phellos

4. Leaf broad, about 2-3 times as long as broad — Shingle oak Quercus imbricaria

5. Lobes or teeth bristle-tipped: 65. Lobes or teeth rounded or blunt-pointed, no

bristles: 7

6. Leaves mostly with 3 lobes — Blackjack oak Quercus marilandica

6. Leaves mostly with 7-9 lobes — Northern red oak Quercus rubra

7. Leaves with 5-9 deep lobes — White oak Quercus alba

7. Leaves with 21-27 shallow lobes — Swamp chestnut oak Quercus prinus

http://en.wikipedia.org/wiki/Dichotomous_key