Lesson 1 - Identifying, Naming, and Classifying Species
Transcript of Lesson 1 - Identifying, Naming, and Classifying Species
Lesson 1 - Identifying, Naming, and Classifying Species
Species = a group of organisms that can interbreed in nature and produce fertile offspring
About 2 million species have been identified on Earth to date
o Estimated to be between 5 million to 20 million
Not just biologists need to know the identity of different species
o Doctors, border inspection officials (invasive species), farmers, zoo keepers
Identifying and Naming New Species
Three species concepts are used to help define species
o Each one focuses on a different aspect of an organism
Morphological species concept focuses on morphology – body shape, size, and other structural
features
Biological species concept define species on the basis of whether two organisms can produce fertile
offspring
Phylogenetic species concept examines the phylogeny, or evolutionary history, of organisms
Naming Species
Most familiar organisms have been given several names that differ from continent to continent, country
to country, and often region to region within the same country
o E.g. in English-speaking N.A. alone, groundhog = woodchuck = whistle pig = forest marmot
Taxonomy = the branch of biology that identifies, names, and classifies species based on natural
features
o Father of Taxonomy is Carolus Linnaeus
o Developed the system for naming species: binomial nomenclature
Name of the organism is known as the species name or the scientific name
Binomial nomenclature = the system of giving a two-word Latin name to each species
o first part is the genus
o second part is the species
scientific name is italicized, when typed, with first letter of genus name capitalized and species in lower
case
o E.g. humans = Homo sapiens
If hand written, entire scientific name is underlined
Classification of species requires a set of rules or criteria to be followed
o Linnaeus developed the basis of the system of classification used today
Classification = the grouping of organisms based on a set of criteria that helps to organize and
indicate evolutionary relationships
Hierarchial classification = the method of classifying organisms in which species are arranged in
categories from most general to most specific
Typically a species is classified by placing it in one of eight nested categories
Each of these categories is known as a rank
o E.g. phylum or order
The name of each rank is called a taxon
E.g. Rodenta or Chordata