ANIMAL CLASSIFICATION, PHYLOGENY, AND ORGANIZATION

Zoology Chapter 7

Common namesCrawdads, crayfish, or

crawfish?English sparrow, barn

sparrow, or a house sparrow?

Problem with common names

Vary from region to region

Common names often does not specify particular species

Binomial system of Nomenclature

Universal Clearly indicates the

level of classificationNo two kinds of

animals have the same binomial name

Every animal has one correct name International Code of Zoological Nomenclature

Brings order to a chaotic world of common names

Binomial nomenclature rules

Genus begins with a Capital letter

Entire name italicized or underlined

Homo sapien or H. sapien

Kingdom of Life

1969 R. Whittaker- five kingdom classification

System of classification that distinguished b/w kingdoms according to cellular organization mode of nutrition (Heterotroph or Autotroph)

Kingdom Monera

bacteria and cyanobacteria that are prokaryotic

Kingdom Protista

single or colonies of eukaryotic cells

Amoeba and Paramecium, for example

Kingdom Plantae

eukaryotic, multicellular, and photosynthetic.

Have cell wall, and usually non-motile

Kingdom Fungi

eukaryotic and multicellular.

Have cell wall and non-motile.

Mode of nutrition distinguishes fungi from plant- fungi digest extra-

cellularly and absorb the breakdown products

Kingdom Animalia

eukaryotic and multicellular

usually feed by ingesting other organisms

cell lack cell wallsusually motile (at least

during some part of life cycle)

Challenge of the five class system

Ribosomal RNA excellent for studying evolution

rRNA changes very slow (evolutionary conservation)

Closely related organisms have similar rRNAs

Comparison of rRNA of different organisms concludes All life shares a common

ancestorThree major evolutionary

lineage (domains) and supersedes the kingdom as the broadest taxonomic grouping

The Three Domains

1. Archaea- prokaryotic microbes live in extreme environments that reflect the conditions of early life

the most primitive life form

gave rise to the two other domains

2. Eubacteria- true bacteria and are prokaryotic microorganisms

3. Eukarya- include all eukaryotic organisms, (protists, fungi, plants and animals)

Text devoted to animals

Except for Chapter 8 Animal like protists (Amoeba and Paramecium)

The inclusion of protozoa is part of a tradition

Once considered a phylum (Protozoa) in the animal kingdom

Patterns of Organization

Symmetry: Has a pattern to the body plan

Asymmetry: no pattern to body plan

Draw examples of each in your notes:

1.Radial symmetry2.Bilateral symmetry

Assymetry

Radial Symmetry

Bilateral Symmetry

Divided along sagittal plane into two mirror images Divided into right

and left halvesAnterior= head

endPosterior= tail endDorsal= back sideVentral= belly side

Bilateral Symmetry Adaptation

Important evolutionary advancement Important for active,

directed movement Anterior, posterior

ends One side of body

kept up (dorsal) vs. down (ventral)

Cephalization

Directed movement evolved with anterior sense organs is called cephalization

Cephalization specialization of

sense organs in head end of animals