Slides in this set
The systematic grouping of living organisms according to the
structural or evolutionary relationships among them.
The Concept of a Species
A species is the basic unit of classification.
Organisms in the same species share some common characteristics:
· share a common ancestor
· similar in appearance (morphology), behaviour and biochemistry,
and have the same ecological niche
· can breed together in their natural environment to produce fertile
offspring but cannot breed with members of other species.…read more
Naming the Species
· Carolus Linnaeus devised a common system of naming
· Binomial system organisms were identified using two names
What are the features of the binomial system?
· universal system based upon Latin or Greek names
· first name is known as the generic name represents the genus
to which the organism belongs
· second name known as the specific name denotes the species…read more
What are the minimum rules that should be followed while writing
the scientific name (binomial nomenclature) of an organism?
· The binomial names should be italicised when printed or
underlined if hand-written
· The generic name should start with a capital letter, while the
specific name should start with a small letter only.
· If the species name is not known, it can be written as `sp'.
The naming of organisms is in a constant state of change. Current
names reflect the present state of scientific knowledge and
understanding. In the same way, the classification of species is
regularly changing as our knowledge of their evolution, physical
features, biochemistry and behavior increases.…read more
Two Main Forms of Biological Classification
1) Artificial Classification
· divides organisms according to differences that are useful at the
· usually morphological characters are used
· such features may include color, size, leaf shape etc.
· analogous characteristics same function but different origins
2) Natural Classification
· based on evolutionary relationships b/w organisms & their
· classifies species using shared features derived from their
· arranges the groups into a hierarchy
· homologous characteristics different function but similar origins…read more