Classification. classificationThe activity that involves grouping and naming is called classification. Biologists classify organisms into categories called.

Classification

• The activity that involves grouping and naming is called classificationclassification.

• Biologists classify organisms into categories called Biologists classify organisms into categories called taxataxa..

• The branch of Biology that involves classification of organisms is called taxonomytaxonomy.

Not to be confused with taxidermy!

How to Classify

• Classification is artificial, but helps scientists deal with the great diversity of species and determine relationships.

• With the theory of evolution, we now classify organisms according to ancestry.

• The fossil record can help to make connections between species.

Introducing…. Carl Linnaeus

• Founder of modern Taxonomy• He gave us “binomical nomeclature”, the Two

word Latin name for identifying species:first name is the genussecond name is the species nameboth together we call the species name

1707-1778

There are There are 7 7

taxonomic taxonomic levels:levels:

1.1. KingdomKingdom2.2. PhylumPhylum3.3. ClassClass4.4. OrderOrder5.5. FamilyFamily6.6. GenusGenus7.7. SpeciesSpecies

TaxonomyGreat White Shark Human

Kingdom Animalia Animalia

Phylum Chordata Chordata

Class Chondrichthyes (cartilaginous fish)

Mammalia

Order Elasmobranchii (sharks and rays)

Primates

Family Selachii Hominidae

genus Carcharodon Homo

species carcharias sapiens

Based on three principles: 1.Groups of organisms are descended

from a common ancestor. 2.At each node (divergence of a

population), there are two branching lines of descendants.

3.Evolution results in modifications of characteristics over time.

A branching diagram that depicts species divergence from common ancestors.

They show the distribution and origins of shared characteristics.

We will use a dichotomous key: Presents with two statements that

describe certain characteristics. The statements should be mutually

exclusive (for example, 'it is either red or it isn't‘).

On selecting one, the reader is presented with the next couplet choice in the key and so on

to eventually arrive at an identification.