INTRODUCTION TO SYSTEMATICS Flashcards
Science dealing with the description, classification, identification and nomenclature of extinct and extant organisms and viruses
Taxonomy
Science dealing with the “taxonomy” of biological diversity and the determination of their phylogenetic or evolutionary relationships ➡ Taxonomy + biodiversity + phylogenetic relationships
Systematics
evolutionary relationships
phylogenetic relationships
published a system of taxonomy based on resemblances (=morphological similarity)
Carolus Linnaeus (1707-1778)
Father of Modern Taxonomy
Carolus Linnaeus Carl von Linne)
Carolus Linnaeus and othe name
Carl von Linne
Two key features of Carolus Linnaeus’ system
binomial nomenclature
hierarchical classification
7 taxa / categories
Linnaeus, Systema Naturae,
year
hierarchical classification (1735)
hierarchical classification book and year
Systema Naturae
1735
binomial nomenclature book and year
Species Plantarum
1753
The two-part scientific name of a species is called a binomial
First part of the name = genus
Second part = specific epithet [unique for each species within the genus] The proper way of writing the scientific name : First letter of genus always
CAPITALIZED Specific epithet always in lower cas Must be underlined when handwritten; italicized when typewritten Include author of the name
Uses Latin or Latinized words
Binomial Nomenclature
Linnaeus, Species Plantarum,
year
binomial nomenclature (1753)
The two-part scientific name of a species
Binomial Nomenclature
Binomial Nomenclature rules
First part of the name = genus
Second part = specific epithet
The proper way of writing the scientific name : First letter of genus always
CAPITALIZED Specific epithet always in lower case
Must be underlined when handwritten; italicized when typewritten Include author of the name
Uses Latin or Latinized words
[unique for each species within the genus]
specific epithet
INTERNATIONAL CODES OF NOMENCLATURE (5)
- International Code of Nomenclature of Prokaryotes (ICNP, 2019)
- International Code of Nomenclature for Algae, Fungi, and Plants (ICN) (=Shenzhen Code, 2018)
- International Code of Zoological Nomenclature (ICZN) (2012)
- The International Code of Virus Classification and Nomenclature (ICTV 2018)
- International Code of Nomenclature for Cultivated Plants (ICNCP, 2016)
The scientific naming of plants, algae, and fungi has deep historical roots. A major landmark was the publication in
by + date
1753 of Linnaeus’s Species Plantarum.
The first Code of nomenclature was
by + date
Alphonse de Candolle’s Lois de la Nomenclature Botanique (1867).
PRINCIPLE I: The nomenclature of algae, fungi, and plants is independent of zoological and prokaryotic nomenclature. This Code applies equally to names of taxonomic groups treated as algae, fungi, or plants, whether or not these groups were originally so treated (see Pre. 8).
PRINCIPLE II. The application of names of taxonomic groups is determined by means of nomenclatural types.
PRINCIPLE III. The nomenclature of a taxonomic group is based upon priority of publication.
PRINCIPLE IV. Each taxonomic group with a particular circumscription, position, and rank can bear only one correct name, the earliest that is in accordance with the rules, except in specified cases.
PRINCIPLE V. Scientific names of taxonomic groups are treated as Latin regardless of their derivation.
PRINCIPLE VI. The rules of nomenclature are retroactive unless expressly limited.
International Code of Nomenclature for algae, fungi, and plants (ICN) (=Shenzhen Code, 2018)
there is not a single name that is not associated by a nomeclature type
true
is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described.
It is either the single such physical example (or illustration) or one of several examples, but explicitly designated as the
Holotype
Zoological nomenclature is the system of scientific names applied to taxonomic units (taxa; singular: taxon) of extant or extinct animals.
For the purposes of this Code the term “animals” refers to the Metazoa and also to protistan taxa when workers treat them as animals for the purposes of nomenclature.
International Code of Zoological Nomenclature (ICZN) (2012)
Code of Nomenclature to all Prokaryotes.
International Code of Nomenclature of Prokaryotes (ICNP) (2019)
Code of Nomenclature for algae, fungi and plants;
International Code of Nomenclature for algae, fungi and plants
The nomenclature of viruses is provided for by the
International Code of Virus Classification and Nomenclature.
covers those organisms that are variously recognized as e.g. Schizomycetes, Bacteria, Eubacteria, Archaebacteria, Archaeobacteria, Archaea, Schizophycetes, Cyanophyceae and Cyanobacteria.
“Prokaryotes”
The ICTV is not responsible for classification and nomenclature of virus taxa below the rank of species.
TRUE
The classification and naming of serotypes, genotypes, strains, variants and isolates of virus species is the responsibility of acknowledged international specialist groups.
TRUE
Artificially created viruses and laboratory hybrid viruses will not be given taxonomic consideration. Their classification will be the responsibility of acknowledged international specialist groups.
TRUE
Taxa will be established only when representative member viruses are sufficiently well characterized and described in the published literature so as to allow them to be identified unambiguously and the taxon to be distinguished from other similar taxa.
TRUE
classification of 7 taxa (taxon, sing.) / ranks / categories = K,P,C,O,F,G,S
Hierarchical classification Carl Linnaeus - (1735)
7 taxa
Kingdom
Phylum
Class
Order
Family
Genus
Species
the evolutionary history of a species or group of organisms
can be shown in a branching phylogenetic tree (=cladogram).
Phylogeny
origination and development of an organism, usually from the time of fertilization of the egg to adult. The term can also be used to refer to the study of the entirety of an organism’s lifespan.
Ontogeny
The evolutionary history of a group of organisms can be shown in a branching
phylogenetic tree =cladogram
Phylogeny indicates birds as a subgroup of reptiles
Systematists have proposed a classification system that would recognize only groups that include a common ancestor and all its descendants
TRUE
Linnaean classification and phylogeny can differ from each other
TRUE
an unresolved pattern of divergence.
polytomy
represents a hypothesis about evolutionary relationships Each branch point represents the divergence of two species
phylogenetic tree
Tree branches can be rotated around a branch point without changing the evolutionary relationships
true
are groups that share an immediate common ancestor
Sister taxa
includes a branch to represent the last common ancestor of all taxa in the tree
rooted tree
diverges early in the history of a group and originates near the common ancestor of the group
basal taxon
branch from which more than two groups emerge
polytomy
Pre-existing feature? ancestral feature
Plesiomorphy
Pre-existing feature? shared ancestral feature in other taxa
Symplesiomorphy
New feature? derived feature
Apomorphy
New feature? shared derived feature in other taxa
Synapomorphy
Systematists gather what types of data for phylogeny
morphological and molecular data (genes and biochemistry) of living organisms and analyze fossil records.
phenotypic and genetic similarities due to shared ancestry are
homologies
Organisms with similar morphologies or DNA sequences are likely to be more closely related than organisms with different structures or sequences
true
similarity due to shared ancestry
Homology
is similarity due to convergent evolution
Analogy
occurs when similar environmental pressures and natural selection produce similar (analogous) adaptations in organisms from different evolutionary lineages.
Convergent evolution
All forms of life share a common ancestor.
true
Taxa which share a common ancestor more recent in time are more closely related to one another than they are to a taxon whose common ancestor is further back in time.
true
Each change in a nucleic acid = one evolutionary event!
true
The more events, the more distantly related are the species. Fewer events means that a species is more closely related
true
A phylogenetic tree is also called a
cladogram
Each branch in the tree is called a
a group of species that includes a common ancestor and all its descendants.
clade
consists of a common ancestor and all its descendants. “single tribe” Only qualify as legitimate taxa derived from cladistics.
Monophyletic clade
consists of an ancestor and some but not all of the descendants. does not meet the cladistic criterion
Paraphyletic clade
consists of various species with different ancestors; lacks a common ancestor Fails the cladistic test
Polyphyletic clade
homologous characters that are shared by more than one taxone.g. backbone is shared by mammals and reptiles.
Shared primitive characters
an evolutionary novelty that is unique for a particular clade.
Shared derived characters
Classification Schemes
Classical/Artificial
Phenetics / Natural
Cladistics
Classification Schemes based on few observable characters
Classical/Artificial
Classical/Artificial example
e.g. Linnaeus Sexual System and Theophrastus form system of plant classification
a simple and practical method of dividing the plant kingdom into groups, based on the arrangement of stamens and pistils
Linnaeus Sexual System
categorized plants into four categories: trees, shrubs, under shrubs, and herbs of their habitat, form, and texture. He named and described 480 plants in his book “Historia Plantarum”
Theophrastus form system of plant classification
Constructs phenograms based on overall similarity, largely phenotypic, without regard to evolutionary history; all characters are given equal weights
Phenetics / Natural
Phenetics / Natural example
Sneath and Sokal Numerical Taxonomy (1973)
constructs cladograms anchored on assumed phylogenetic relationships
Cladistics
Cladistics example
Willi Hennig Phylogenetic Systematics (1966)
the formal name for the field within biology that reconstructs evolutionary history and studies the patterns of relationships among organisms.
Willi Hennig Phylogenetic Systematics (1966)
book BY CHARLES DARWIN, + date
THE ORIGIN OF SPECIES BY MEANS OF NATURAL SELECTION, OR THE PRESERVATION OF FAVOURED RACES IN THE STRUGGLE FOR LIFE. 1859
Proposed the Phylogenetic Taxonomy of Flowering Plants - Based classification on 28 guiding dicta to determine level of being simple/complex, primitive/advanced
Charles Bessey (1845-1915)
how did charles bessey illustrate his findings on flowering plants?
cactus tree
Premolecular classification
Artificial Natural Phylogenetic
Molecular classifications
Phylogenetic
Phylogenetic based on a wide array of characters including the molecular and micromorphological level (based on the Angiosperm Phylogeny Group)
Plant Classification System
Postmolecular Classification
is an informal international group of systematic botanists who collaborate to establish a consensus on the taxonomy of flowering plants that reflects new knowledge about plant relationships discovered through phylogenetic studies.
Angiosperm Phylogeny Group
Plant Classification Systems
Molecular
Pre molecular
Post molcular
2- Kingdom
Vegetabilia
Animalia
(Linnaeus, 1735)
3-kingdom
Protista
Animalia
Plantae
(Haeckel, 1866)
4-kingdom
Monera
Protista
Plantae
Animalia
(Copeland, 1938)
5-kingdom
Monera
Plantae
Fungi
Protista
Animalia
(Whittaker, 1969)
6-kingdom
Eubacteria
Protista
Archaebacteria
Fungi
Animalia
Plantae
(Woese, 1977)
3-Domain
Bacteria
Archaea
Eukarya
(Woese,1990)
Six-Kingdom Classification (Woese, 1977)
(kingdom with domain)
Kingdom Eubacteria (domain Bacteria)
Kingdom Archaebacteria (domain Archaea)
Kingdom Protista (domain Eukarya)
Kingdom Fungi (domain Eukarya)
Kingdom Plantae (domain Eukarya)
Kingdom Animalia (domain Eukarya)
