Systematics: The Science Of Biological Diversity Chapter 12 Systematics- the scientific study of...
Transcript of Systematics: The Science Of Biological Diversity Chapter 12 Systematics- the scientific study of...
Systematics: The Science Of Biological Diversity
Chapter 12
• Systematics- the scientific study of biological diversity and its evolutionary history.
Theophrastus (370-285 B.C.)
• Father of Botany, student of Aristotle.
• Classified plants based on form.– Tree– Shrub– Undershrub– Herb
Atropa belladonna- Solanaceae
Carol von Linné (1707-1778)
• Swedish naturalist.
• Species Naturae & Plantarum.– Plant descriptions.– Plant binomials- a two-term
system of nomenclature.• Genus and species (specific
epithet).• Example- catnip.
– Nepeta cataria L.– “Nepeta floribus interrupte spicatus
pedunculatis”
Nepeta cataria- Lamiaceae
Taxonomy
• Taxonomy- (gr. taxis- arrangement, nomos- law) the science of the classification of organisms.– Identifying, naming, classifying organisms.
• Domain• Kingdom• Phylum- phyta• Class- phyceae• Order- ales• Family- aceae• Genus• Species
Prokaryotes and Eukaryotes
Prokaryotes Eukaryotes
Eukaryote Lineages
Origin of Cells
Origin of Eukaryotic Cells
Species Concepts
International Code of Botanical Nomenclature (ICBN)
• Aim- to provide a stable method of naming taxonomic groups. – Principle I- botanical nomenclature is independent of
zoological and bacteriological nomenclature. – Principle II- names of taxonomic groups are
determined by means of nomenclatural types. – Principle III- nomenclature of a taxonomic group is
based upon priority of publication.
• Naming- the purpose of giving a name to a taxonomic group is not to indicate its characters or history, but to supply a means of referring to it and to indicate its rank.
Taxonomic Terminology
• Taxon- a taxonomic group of any rank (plural: taxa).• Synonym- two or more names that apply to the same
taxon.• Basionym- the original name of a taxon. • Author/s- the first person or persons to describe a taxon.• Revisionary author/s- the person or persons that
modified the name. • Etymology- the derivation, origin, or history of a word.• Type Specimen- a specimen designated to serve as a
reference point for a scientific name.– Holotype– Lectotype
Taxonomic Names • Species names consists of the genus
name, plus the specific epithet.
• Members of a species may be grouped into subspecies or varieties.
How do you identify plants?
• Ask an expert.• Use a herbarium.• Compare plant with a written description.• Use books to picture I.D. specimens.
– Photographs and illustrations.
• Use a dichotomous key.
Dichotomous Keys
• A method employed for identifying unknown organisms.
• A dichotomous key is constructed of a series of couplets, each consisting of two separate statements.1. Flowers white .................. Plant A
1. Flowers red or yellow ..... 22. Petals red ............ Plant B
2. Petals white ........ Plant C