Unit Two: Biodiversity Biology 112

Outcome: Students should be able to: Understand the concept of binomial nomenclature as developed by Linneaus and understand its advantages for the scientific community

Principles of Taxonomy Classification systems are used to name organisms and group them in a logical manner Taxonomy is the study of classification of living things Organisms are living things that can be assigned a classification based on their physical characteristics

Assigning Scientific Names Referring to organisms by their common name can be confusing Scientists have agreed to use a single name for each species A species is a group of similar organisms that can breed and produce fertile offspring Latin and Greek are used when assigning scientific names

Binomial Nomenclature Carolus Linneaus (1707-1778) developed a two word naming system called binomial nomenclature for all species It is always written in italics, the first word is always capitalized and the second word in lower case The first word indicates the genus (closely related organisms) to which the species belongs The second word indicates the species, which may give indication about a particular trait of the organisms Sometimes, there is a third word to indicate a subspecies (which is called trinomial nomenclature)

Example of Binomial Nomenclature Canis lupus is the gray wolf with over 37 subspecies - binomial One of those subspecies is the domestic dog, which is named Canis lupus familiaris - trinomial

Check for Understanding Do the organisms Ursus arctos and Ursus maritimus belong to the same genus? Same species? What characteristic do you feel as though the word ‘arctos’ conveys? ‘maritimus’?

Linnaeus’s Classification System There are 7 levels that are considered to be hierachical – from largest to smallest Each of these levels is called a taxon or taxonomic category Kingdom Phylum Class Order Family Genus Species

Kingdom – plants and animals

Phylum Organisms share certain characteristics One such phylum include mammals, whom belong to Phylum Chordata

Class Class Mammalia Narrows the characteristics further In this case, all the characteristics of the phylum chordata with the addition of warm-blooded, have body hair and produce milk for their young

Order Similar families are grouped into an order Order carnivora All the characteristics of class mammalia with the addition of meat eaters

Family A group of genera that share many common characteristics

Genus and species Homo sapien

For the remainder of class… Textbook – read pages 447-450 and complete the gudied reading for Section 18.1 Complete question 6 on page 450 Complete the question in the envelope... Section 18-1 Review – due the end of class