Systematics Flashcards
(28 cards)
Systematics
def: Naming of organisms, arranging them in categories in a classification, and discovering their relationships
- it is a combination of names and categories
names
purpose: to talk to others and know what they are referring to.
categories
- organisms can be related to each other
- categorizing things is NOT the same as determining relatedness
taxonomy
def: describing species and other levels of taxa, arranging the taxa into categories - naming stuff
nomenclature
def: proper use of rules to name species and higher taxa - legal aspect of science
phylogeny
def: taxonomic arrangement of species built on the perceived phylogenies of a species
linnaean classification
- binomial nomenclature based on shared characters
- classified all life into 3 kingdoms (animal, plant, mineral)
- Only a few terms from his original publication are still used today
Apostles of Linnaeus
- group of 17 students
- appointed by Linnaeus to carry out special botanical and zoological expeditions to describe as many noel species as possible
- Linnaeus named many taxonomic groups after his students
Binomial Nomenclature
- 2 name system of naming
- simplified naming (a name could have 9 part description)
- Genus species
Systema Naturae
the name of the system Linnaeus used to classify species
Latin Name
-used to describe binomial nomenclature
Common Name
- used commonly for a species
- usually named locally
- A single species can have many common names or no common name at all
- The same common name can be used for many different species
Linnaean hierarchy
-tells us nothing about evolutionary relationships
Taxonomic ranks
taxonomic ranks beyond the species name are artificial
-taxonomic ranks are not defined by the same traits across taxa
Super-
above the named taxonomic rank
Sub-
below the named taxonomic rank
Characters
observable, quantifiable traits of a species,
Characters are the raw material of taxonomy and phylogney
The Code and Principle of Priority
The Code - a set of rules that govern *formation, *publication, and *usage of names
-Priority is the basic principle of the code: oldest name for a taxon is the valid name (prevents name changes as a result of disagreements)
- Names must be in latin form
- Names must be in Roman alphabet
- Names for species are binomial
Synonyms
More than one name for the same taxon
-mainly due to differences of opinion in species limits, or people unaware of each other’s work
Homonyms
more than one taxon with the same name
-mainly due to people unaware of each other’s work, not checking the literature
Holotype
Objective standard of reference by which the application of name is determined
-ONE entity designated as the name-bearing type ie name-bearing type of a genus is a type species
Isotype
-Where a holotype consists of more than one piece (ie more common with plants, where the holotype may be a herbarium specimen found in more than one piece)
Neotype
- a new holotype selected to replace the original holotype
- most often used for species defined from fossils (ie a more complete fossil is found)
From a naming system to nomenclature - code of nomenclature
- promote stability and universality
- name of each taxon is unique and distinct