Systematics is the study of the historical relationships between biological organisms and the understanding of biodiversity. It aims to trace phylogeny and classify taxa in an evolutionary context. Systematics encompasses fields like taxonomy, classification, nomenclature, biogeography, and phylogenetics. It determines the unique and shared properties of species and higher taxa, classifies life to make diversity accessible to other disciplines, and has contributed insights in areas like epidemiology, agriculture, and conservation through accurate identification and classification of organisms.

1. Systematics- is the study of the historical relationships of groups of
biological organisms- the recognition and understanding of
biodiversity. Tracing phylogeny is one goal of systematics hence, it
is considered the study of biological diversity in an evolutionary
context.
WHAT IS SYSTEMATICS?
DEFINITION
G. G. Simpson in 1961 – defined it as the scientific study of the
kinds and diversity of organisms and of any and all relationships
among them. (The science of diversity of organisms)
Phenetic- similarity
Phylogenetic- kinship by descent from common ancestors
Trophic- food relationship
Geographic- spatial
-The term systematics stems from the latinized Greek word
systema as applied to the systems of classification developed by
early naturalists.

2. WHAT IS SYSTEMATICS?
SCOPE
1. Deals with populations, species and higher taxa
2. Using the comparative methodology, determines what:
a. The unique properties of each species and higher
taxa are
b. Properties certain taxa have in common
c. The biological causes of the differences or shared
characters are
3. Concerned with variation within taxa
4. Classifies taxa making organic diversity accessible to
other disciplines

3. SYSTEMATICS ENCOMPASSED THE FF.
FIELDS/STUDIES
 1. Biodiversity
 2. Taxonomy
 3. Classification
 4. Nomenclature
 5. Biogeography
 6. Evolutionary Biology
 7. Phylogenetics

4. WHAT IS SYSTEMATICS?
CONTRIBUTIONS
1. Applied Biology
a. Epidemiology of malaria in Europe
Supposed vector, Anopheles maculipennis Meigen – found
throughout Europe
But malaria restricted to local districts
Careful taxonomic studies:
- Maculipennis = several sibling species: different
habitats/breeding habits; only some species are vectors of
malaria
- Control directed to specific areas

5. WHAT IS SYSTEMATICS?
CONTRIBUTIONS
2. Other Fields
a. Agriculture
b. Public health
c. Ecology
d. Conservation
e. Genetics
f. Behavioral Biology
Correct identification and classification of species in:

12. 1. Discovery and extinction of species.
2. Sources of important products:
a. Herbal medicines
b. Forests products
Estimated number of species:
EXTANT = 10M – 100M; EXTINCT = 0.5B
c. Fossil fuels
d. Other plant and animal products

13. We have to know what we are referring to
b. Determination
Knowing the name of the group (taxon) to which an unknown belongs
The use of Taxonomic Keys
a. Identification
Taxonomic characters
c. Nomenclature
Naming an organism (bionomial name; scientific name)
Descriptive terminology

22. PROCESSES INCLUDED IN SYSTEMATICS
 1. Identifying the basic systematic unit (species);
 2. Discovering the patterns of relationships of species
at successively higher levels;
 3. Building classifications based on these patterns &
naming appropriate taxa;
 4. The application of this pattern knowledge to
studying changes in organismal features through time.
 Moreover, it also includes the building & maintenance
of biodiversity collections, upon which all the products
of systematic studies are based.

23. THE CONTRIBUTION OF SYSTEMATICS TO
BIOLOGY
 No other branch of biology has made a greater contribution to our
understanding of evolution.
 No thorough ecological survey can be conducted without the most
painstaking identification of all species that are of ecological
importance.
 In the delimitation of geological strata, key fossil species have played a
decisive role.
 Molecular biologists are virtually interested in a sound classification. The
evolution of molecules, an increasingly important area of research, can
be understood only against the background of a sound classification.
 Made contributions on applied sciences-medicine, public health,
agriculture, conservation, management of natural resources.