Classification of Living Things UNIT 16 Articles from digital text: http://ic.galegroup.com/ic/scic/ReferenceDetailsPage/ReferenceDetailsWindow?failOverType=&query=&windowstate=normal&contentModules=&mode=view&displayGroupName=Reference&limiter=&currPage=&disableHighlighting=&displayGroups=&sortBy=&source=&search_within_results=&action=e&catId=&activityType=&scanId=&documentId=GALE%7CCV2641700052&userGroupName=catholiccenhs&jsid=990ac2d19b8fe56ed0765c3f4ac8787e

Learning Objectives Living things can be classified based on structural evidence embryological evidence evolutionary evidence molecular (relatedness of DNA sequence) evidence Carolus Linnaeus developed the system of taxonomy and binomial nomenclature that is still in use today.

Classification Method of organizing plants and animals into categories based on their appearance and the natural relationships between them DNA composition is most reliable method for identifying the relationships among organisms Taxonomy science of classifying organisms makes sense of the diversity of life in order to study it better

Aristotle Began arranging organisms according to their physical similarities (previously – useful vs. harmful) animals: red blood (vertebrates) vs. no red blood plants: size; herbs, shrubs, trees

Benefits of Classification Helps biologists keep track of living things study their differences and similarities learn how living things are related to one another through evolution (the process by which living things change over generations) save time and effort

Benefits of Classification Today’s system: natural system since it represents genuine relationships between organisms the more closely organisms are related to each other, the more features they have in common hierarchical – categories are grouped according to size in a series of successively larger ranks

Carolus Linnaeus Swedish physician and naturalist (1707-1778) “Father of taxonomy” Established 1st orderly system of classifying living things Introduced binomial nomenclature His system was able to impose a much-needed order on the study of life 

Classification Groups Taxons (groups) range in order of specificity General to specific Domain Kingdom Phylum Class Order Family Genus Species  

Classification Examples Animal Diversity Web