Classification Chapter 18

How are living things organized for study?

Classification To study the __________ of life, biologists use a classification system to __________ organisms and ___________ them in a logical manner Why? Common names can be confusing (buzzard) or misleading (starfish) Taxonomy: discipline of ____________organisms and assigning each organism a universally accepted _______ In science we use ___________ ___________, a 2-part naming system developed by Carolus ___________ (1700s).

Binomial Nomenclature Rules: Both words must be in ____________ or underlined. The first letter of the first word (the ________) is _____________. The second word (the _________) is in _________________. Always written in ______________ ( language most of English is derived from) Example Felis catus

Kingdoms and Domains There are 2 different Systems of Classification: ________________________ Monera Eubacteria Archaebacteria Protista Fungi Plantae Animalia _____________________________ (“superkingdoms”) Archaea Bacteria Eukarya

Classification System Linnaeus created a classification system based on organism’s _____ and ___________. He created 7 _____ (classification “groups”, domain added later) from __________ to most specific: Domain Kingdom Phylum Class Order Family Genus Species Dumb Kings Play Cards On Fat Green Stools

Brown Squirrel Kingdom: _____________ (“is an animal”) Phylum: Chordata (“has a spine”) Class: ____________ (“nurses its young”) Order: Rodentia (“has long sharp front teeth”) Family: ____________ (“has a bushy tail”) Genus: Tamiasciurus (“climbs trees”) Species: _________________ (“has brown fur on its back and white fur on its underparts”)

How do we determine how similar or how dissimilar certain organisms are?

Cladistics Cladistics is one method of _________________phylogenies (how they are related) based on ______________ traits. Patterns of ____________ characteristics ______________ traits are new characteristics that arise as lineages evolve over time. These derived traits are displayed on a cladogram. Shows the ________________ relationships among a group of organisms

Cladogram

DICHOTOMOUS KEY A tool used to identify ____________ or _______________. A list of characteristics become more ______________ as they describe the particular item of interest. Forced-choice selection between two characteristic options Follow directions next to characteristic until you get to a species (like “choose your own path books”)