BIO127 LEC Exam 1 (Systematics and Phylogenetics)

Coverage: Systematics and Phylogenetics; Survey of Philippine Medicinal Taxa; Philippine Ethnobotany and Ethics

1. Multicellular

2. Eukaryotic

3. Photosynthetic

4. Autotrophs

The main four characteristics of a plant?

1. Foundations of our ecosystem

2. Oxygen production

3. Support agriculture

4. Source of food, resources, medicine

5. Climate regulation through the consumption of carbon dioxide gas

6. Culturally important

Key importances of plants

Endosymbiotic Theory

Proposed that chloroplasts originated from a host eukaryote cell engulfing a prokaryotic cell

Cyanobacterium

Prokaryote engulfed by eukaryotic cell in endosymbiotic theory

(DINC)

• Description

• Identification

• Nomenclature

• Classification

The four pillars of taxonomic research

Taxonomy

Science of naming, describing, and classifying organisms that includes all plants, animals, and microorganisms

Secondary endosymbiosis

Engulfment of another eukaryote cell of the ancestral chloroplast-containing eukaryote

Systematics

Science that encompasses traditional taxonomy with the primary goal of reconstruction of phylogeny

Reconstruction of phylogeny

Primary goal of Systematics

Phylogeny

Evolutionary history or relationships among organisms

Taxa (s. Taxon)

Group of shared organisms

Description

Assigning characters or features and attributes to a taxon

Identification

Process of associating an unknown taxon to a known one or determining an unknown entity yet to be formally named and described

Dichotomous key

Tool used to identify organisms or objects by choosing between pairs of contrasting, observable characteristics

Leads

Contrasting statements in dichotomous key

Couplet

Pair of leads in a dichotomous key

Nomenclature

Formal naming of taxa

International Code of Nomenclature (ICN) or International Code of Binomial Nomenclature (ICBN)

Institution governing formal naming of taxa

1. Naming new, previously unknown, undescribed taxa

2. Determining the correct name for previously known taxa in the event that their rank has changed, transferred, united or divided

2 main activities of ICN

Classification

Hierarchical organization of taxa by rank

• Kingdom

• Phylum (or Division)

• Class

• Order

• Family

• Genus

• Species

King Philip Came Over For Good Soup

Taxonomic classification ranks from most inclusive to least inclusive

Secondary Rank

Provides additional levels of classification when necessary

1. The nomenclature of algae, fungi, and plants is independent of zoological and prokaryotic nomenclature

2. The application of names of taxonomic groups is by determined by means of nomenclatural types.

3. Nomenclature of a group is based upon priority of publication.

4. A taxonomic group can bear only one correct name, the earliest that is in accordance with the rules, except in specified cases (conserved name).

5. Scientific names of taxonomic groups are treated as Latin regardless of their derivation

6. The rules of nomenclature (ICN) are retroactive, or applicable to dates before legislation, unless expressly limited

Six Principles of Plant Nomenclature

Scientific Name

Taxonomic names assigned by the rules of the ICBN

Binomial/binary nomenclature

Formal two-term naming system where each name is composed of two parts

Membrane-bound nucleus and membrane-bound specialized organelles

What differentiates eukaryotes from prokaryotes?

Trinomial or Ternary nomenclature

Extension of the standard two-part binomial system by adding a third, specific epithet (subspecies, varieties, or forms)

-us, -er, -is, -r

Latin genders (Masculine)

-a, -ra, -is, -ris

Latin genders (Feminine)

-um, -rum, -e, -re

Latin genders (Neuter)

Tree genera are treated as feminine regardless whether their Latin ending suggests a masculine gender

Exception of Latin gender regarding tree genera

Xanthoxylon

Commemorative name which means “yellow wood“

Hepatica

Commemorative name which means “liver-like“

Hygrophila

Commemorative name which means “marshy-habit“

Acanthospermum

Commemorative name which means “spiny fruit“

Narcissus

Commemorative aboriginal name in Greek

Ginkgo

Commemorative aboriginal name in Chinese

Vanda

Commemorative aboriginal name in Sanskrit

Sasa

Commemorative aboriginal name in Japanese

1. Not formally published

2. Ambiguous

3. Not universal

4. One organism can have multiple common names

5. A common name can be used for multiple organisms

6. Tell nothing about rank and classification

Disadvantages of vernacular or common names

Nomenclature Type

Physical specimen to which the name of a taxon is permanently attached

Herbarium

Single specimen or organized collection of dried, pressed, plant specimens for scientific study and biodiversity research

1. Color Chart

2. Scale Bar

3. Barcode

4. Labels

5. Institution Name

Elements of an herbarium sheet

Global Plants Initiative (GPI) and Department of Energy (DOE)

Example of organizations dedicated to digitization of herbarium specimens

Holotype

Serves as a definitive reference source upon which a name is based, originally used, or designated at the time of its valid publication.

Isotype

Duplicate specimen of the holotype, collected at the same time by the same person from the same population.

Lectotype

Specimen that is selected from the original material to serve as the type when no holotype was designated at the time of publication.

Neotype

A specimen derived from a nonoriginal collection that is selected to serve as the type as long as all of the material on which the name was originally based is missing

Syntype

Any specimen cited in the original work if no holotype is designated, which can be multiple.

Isosyntype

A duplicate of a syntype

Paratype

A specimen not formally designated as a type but cited along with the type collection in the original description of a taxon. It is not a holotype, isotype, or syntype.

Epitype

Selected to serve as an ”interpretive” type if the holotype, lectotype, or neotype is ambiguous with respect to the identification and diagnosis of the taxon.

Authorship

Indicates the person or group of people responsible for the first valid publication of a scientific name.

Rosaceae Jussieu

Alternate citation of Rosaceae family

Conostylideae Lindley

Tribe published by John Lindley

Mohavea confertiflora (Bentham) Heller or Mohavea confertiflora (Benth.) A. Heller

Species name of Mohavea confertiflora with authorship epithets

George Bentham

First publisher of confertiflora under the genus Antirrhinum

Amos Arthur Heller

Author who corrected Bentham, transferring confertiflora to Mohavea

“Those who wish to remain ignorant of the Latin language, have no business with the study of botany”

Quote by naturalist John Berkenhout

Tautonym

Scientific name for a species where the genus and the specific epithet are identical in spelling. Permitted in International Code of Zoological Nomenclature (ICZN)

1. Illegitimate (not recognized by taxonomists)

2. Informal (not used in Systematics)

3. Non-descriptive

3 reasons why tautonym is invalid in taxonomy of plants

1. Discovering the History of Life

2. Identifying Evolutionary Novelties

3. Documenting and Cataloging Biodiversity

4. Establishing Phylogenetic Classifications

5. Providing Context for Comparative Biology

6. Conservation

Importance of Systematics

Evolution

Foundation of systematics

Evolution

Cumulative changes in life since the origin of the universe. It is descent with modification.

Descent

The transfer of genetic material (enclosed within a cell) from parent(s) to offspring over time.

Lineage or Clade

A set of organisms interconnected through time and space by the transfer of genetic material from parents to offspring. Have a single line of descent from a common ancestor.

Modification

A change in the genetic material that is transferred from parent(s) to offspring, such that genetic material of the offspring is different from that of parent(s).

Population

A group of individuals of the same species that is usually geographically delimited and that typically have a significant amount of gene exchange.

Species

A distinct lineage that, in sexually reproducing organisms, consists of a group of generally intergrading, interbreeding populations that are essentially reproductively isolated from other such groups.

Cladogram or phylogenetic tree

Representation of phylogeny

Cladistics

A methodology for inferring the pattern of evolutionary history of a group of organisms, utilizing apomorphies.

Phylogenetic Tree

A branching diagram that serves as a conceptual estimate of the phylogeny— the evolutionary history or pattern of descent— of a group of organisms.

Monophyletic group

Consists of a common ancestor and all of its descendants

Taxons/Terminal Taxa

Specific organisms or groups located at the tips of the lineages (branches)

Lineages/Branches

Lines of a cladogram represent the sequence of ancestral-descendant populations through time

Nodes

Point where a lineage splits into two separate lines

Apomorphy

Derived trait or character state that is unique to a species or group of organisms and sets it apart from its older ancestor

Synapomorphy

An apomorphy that is shared by two or more groups and a marker for the most recent ancestor.

Plesiomorphy

Ancestral or primitive trait that is retained.

Autapomorphy

A unique, derived trait restricted to a single taxon

• Provides identity and a systematized manner of organization among organisms for ease in DINC

• Taxonomy, systematics, and phylogenetics perform in harmony with the goal of further understanding the evolutionary history and properties of plants.

Interrelation of Taxonomy, Systematics, and Phylogenetics

• Drive discovery of new medicinal plants

• Understand evolutionary origins of medicinal properties

• Provides a standard naming system

• A more extensive study, not limited to morphology, extending to genetics

Taxonomy, Systematics, and Phylogenetics on Medicinal Botany