This document discusses the key concepts and components of systematics, which includes taxonomy and phylogeny. It covers topics such as: - The goal of phylogenetic reconstruction and evolutionary history. - The major parts of systematics including description, classification, nomenclature, and identification. - Tools for communicating taxonomic information such as keys and scientific names. - Methods for determining evolutionary relationships including cladistics and cladograms. - Principles of formal taxonomic naming and types of specimens. - Uses of keys to identify unknown taxa.

1. JJA Obico, Instructor
Department of Biology
U i it f th Phili i M ilUniversity of the Philippines Manila

2. A science that includes traditionalA science that includes traditional
taxonomy and phylogeny
GOAL:
Phylogenetic reconstructionPhylogenetic reconstruction
- evolutionary history of life

3. Major parts of systematics that includesMajor parts of systematics that includes
four components
A DescriptionA. Description
B. Classification
C NomenclatureC. Nomenclature
D. Identification
Taxon- subjects under study; any group
of organismsof organisms

4. Assignment of features or attributes to aAssignment of features or attributes to a
taxon
Characters
Character states- two or more forms of
characters
Example:Example:
• petal color: yellow, blue
• Leaf shapes: lanceolate, ovatep
Tools for communication
Categorizing and delimiting the attributes
f tof a taxon

5. a statement of its characters which thusa statement of its characters, which thus
constitutes the definition of the taxon
Taxonomic characters
• Characters contributing to the description• Characters contributing to the description

6. Including Cassuvieae (Cassuviaceae) R.Br., Spodiaceae (Spodiadaceae) Hassk., Spondiaceae
(Spondiadaceae) Kunth(Spondiadaceae) Kunth
Excluding Blepharocaryaceae, Julianaceae, Pistaciaceae, Podoaceae
Trees, or shrubs. Plants non-succulent. Leaves nearly always alternate (opposite in Bouea);
simple, or compound; when compound, ternate, or pinnate; exstipulate.
Plants hermaphrodite, or monoecious, or dioecious, or gynodioecious, or
polygamomonoecious.p yg
Flowers in panicles.The terminal inflorescence unit racemose. Flowers typically 5 merous.
Perianth with distinct calyx and corolla, or sepaline. Calyx basally gamosepalous.
Androecial members free of the perianth; when coherent 1 adelphous (the filaments
sometimes basally connate). Stamens (1–)5–10(–12).
Gynoecium 1–3–5(–6) carpelled.The pistil 1–5 celled. Gynoecium syncarpous; semicarpous
( l ) i t l i i ( ll ) tl i f i O(rarely), or synovarious, or synstylovarious; superior (usually), or partly inferior. Ovary
1–5 locular. Stigmas non-papillate. Placentation when bi- or plurilocular basal. Ovules in
the single cavity when unilocular, 1; apotropous; anatropous; unitegmic, or bitegmic;
crassinucellate.
Fruit when dry indehiscent; a drupe. Seeds non-endospermic.
CC3.
Widespread in the tropics, also Mediterranean, E. Asia, America.
Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Rutiflorae; Sapindales. APG
(1998) Eudicot; core Eudicot; Rosid; Eurosid II; Sapindales. Species 600. Genera about 70.
Including commercially important fruits — cashew-nut (Anacardium, and the fleshy
peduncle,‘cashew-apple’), mango (Mangifera), Jamaica plum, hog-plum, imbup , pp ), g ( g ), J p , g p ,
(Spondias). Resins, oils and lacquers from Toxicodendron.

7. Arrangement of taxa into some type ofArrangement of taxa into some type of
order
System for cataloguing and expressingSystem for cataloguing and expressing
relationships between taxa
Grouping and RankingGrouping and Ranking

8. RANK TAXA___________
Kindgom PlantaeKindgom Plantae
Division Magnoliophyta
Class Liliopsida (monocots)p ( )
Order Arecales
Family Arecaceae
Genus Cocos
Species Cocos nucifera
Primary ranks- ICBN
Some ranks have particular ending/suffixSome ranks have particular ending/suffix
Ranks are hierarchical

9. PheneticPhenetic
- classification based on overall
similaritiessimilarities
- common to everyone
Phylogenetic
classification based on evolutionary- classification based on evolutionary
history or pattern of descent

10. Can be arbitraryCan be arbitrary,
e.g., classify these:

11. Represented in the form of a cladogram/Represented in the form of a cladogram/
phylogenetic tree
CladogramCladogram
• Lines- lineage or clades; denote descent
• Branching- divergence from a common ancestorBranching divergence from a common ancestor
Evolution recognized as a change from
pre-existing character state(ancestral) topre existing character state(ancestral) to
a new (derived) character state

12. All of life is interconnected byAll of life is interconnected by
TAXA
descentdescent
A B C D E F
TIME
lineage
or clade
TIME
Cladogram or Phylogenetic TreeCladogram or Phylogenetic Tree

13. A B C D E F
TAXA
TIME
speciation
Cladogram or Phylogenetic Tree

14. CladisticsCladistics
Methodology of inferring the pattern of
evolutionary history of a group ofevolutionary history of a group of
organisms using apomorphic characters
Ancestral character
Pleisiomorphy- Pleisiomorphy
Derived character
- Apomorphy- Apomorphy

15. Apomorphies the result of evolutionApomorphies - the result of evolution.
Taxa sharing apomorphies underwentTaxa sharing apomorphies underwent
same evolutionary history,
should be grouped togethershould be grouped together.

16. A B C D E F
TAXA
Apomorphies
f B&C
Apomorphy
for taxon D
for taxa B&C
TIME
Apomorphy
for taxa B-F
Cladogram or Phylogenetic Tree

17. Common ancestry
TAXA
A B C D E F
TIME
common ancestor
(of taxon D, E, & F)
Cl d Ph l ti T
common ancestor
(of taxon A & taxa B-F)
Cladogram or Phylogenetic Tree

18. Recognized group in phylogeneticRecognized group in phylogenetic
systematics
Consisting of a common ancestor plus allConsisting of a common ancestor plus all
of its descendants
Sequential listing of monophyletic groupSequential listing of monophyletic group
- serve as a phylogenetic classification
schemescheme

19. A B C D E F
TAXA
monophyletic
group
TIME
t
common ancestor
(of taxon A & taxa B-F)
common ancestor
(of taxon D, E, & F)
Cladogram or Phylogenetic Tree

20. Consisting of a common ancestor but notConsisting of a common ancestor but not
all descendants of that common ancestor
Two or more separate groups each with a
separate common ancestor

21. A B C D E F
TAXA
TIME
common ancestor
(of taxon A & taxa B-F)
common ancestor
(of taxon D, E, & F)
Cladogram or Phylogenetic Tree

22. A B C D E F
TAXA
A B C D E F
TIME
common ancestor
( f t A & t B F)
common ancestor
(of taxon D, E, & F)
Cladogram or Phylogenetic Tree
(of taxon A & taxa B-F)

23. Formal naming of taxa according toFormal naming of taxa according to
standardized system
International Code of BotanicalInternational Code of Botanical
Nomenclature
Scientific names (Latin)Scientific names (Latin)
A taxon will bear ONLY ONE scientific
namename
Binomial system of naming

24. Pterocarpus indicaPterocarpus indica
Underscored or italicized
generic name: always capitalizedgeneric name: always capitalized
specific epithet: not capitalized
Species name: binomialSpecies name: binomial
Binomial nomenclature
• Carolus Linnaeus• Carolus Linnaeus

25. 1 Universal1. Universal-
morning glory and woodbine
yellow bellyellow bell

26. 2 common names are not consistent2. common names are not consistent
- two common names
one common name refers to more than- one common name refers to more than
one species
3 Tells nothing about the rank3.Tells nothing about the rank
Rose
4 Not all organisms have common name4. Not all organisms have common name

27. Principle I. (INDEPENDENCE)Principle I. (INDEPENDENCE)
Principle II. (TYPE)
Principle III. (PRIORITY)
P i i l IV (CORRECT NAME)Principle IV. (CORRECT NAME)
Principle V. (LATINIZED)c p e V ( N )
Principle VI. (RETROACTIVE)

28. HolotypeHolotype
• upon which a name is based, originally used or
designated at the time of publicationdesignated at the time of publication
Isotype
• duplicate of holotype (same time, same person,p yp ( , p ,
same population)
Lectotype
• selected from original material to serve as the
type when no holotype was designated, or the
holotype is missingholotype is missing

29. NeotypeNeotype
• Derived from non-original material to serve as
the type
Syntype
• Any specimen cited in the original work when a
holotype was not designatedholotype was not designated
• Can be one of 2 or more specimens that were
designated as types
Paratype
• Specimen cited but not a holotype, isotype or
syntypesyntype

30. Associating an unknown taxon with aAssociating an unknown taxon with a
known one
Taxonomic KeyTaxonomic Key
• Consists of sequentially choosing among a list of
possibilities until the possibilities are narrowedpossibilities until the possibilities are narrowed
down to one

31. Dichotomous keyDichotomous key
• Series of two contrasting statements
• CoupletsCouplets
• Lead- each statement in the couplet

32. 1 Stamens fused at base into a tube ........……....... Dichelostemma
1' Stamens not fused at base into a tube
2 Fertile stamens 3 ......................................................Brodiaea :
2' Fertile stamens 6
3 Stamens strongly winged at base ...............….......Bloomeria
3' Stamens not strongly winged at base .......….........Muilla

33. 1 Ovary inferiory
2 Ovules two per carpel .............................. Dilatris
2’ Ovules five per carpel ............................. Lachnanthes
1’ Ovary superior
3 Perianth zygomorphic
4 Nectaries present .................................... Wachendorfia
4’ Nectaries absent ..................................... Barberetta
3’ Perianth actinomorphic .............................. Xiphidium

34. Polyclave keyPolyclave key
• Consists of a list of numerous character states
whereby the user selects all of states of that
match the specimen
• Implemented by a computer algorithm
Advantages:Advantages:
1. Still useful if specimen lacks one or
more type of datayp
2. ID will be narrowed down at least if not
ID

41. Written description
• Floras- Flora of Manila (E. Merrill)
Listing of plant taxa of a given region usu.
accompanied by keys and descriptionp y y p
• Monograph
Detailed taxonomy study of all species of a taxonomic
groupgroup
Specimen Comparison
• Herbarium- repository of preserved plant
collections
Image comparison
Expert DeterminationExpert Determination