This document discusses evolution and the taxonomy of living things. It defines evolution as any heritable change in a population over generations. It describes how Charles Darwin theorized that all life evolved from a common ancestor and became more complex over time. It then explains taxonomy as the classification of living things in a hierarchy of domains, kingdoms, phyla, classes, orders, families, genera and species based on their characteristics and evolutionary relationships. The document outlines the key evidence for evolution such as fossils, selective breeding, and homologous structures. It also identifies the agents that drive evolutionary change as mutations, genetic drift, gene flow and natural selection.

1. Evolution &
The Taxonomy
of Living
Things

2. What is
Evolution?

3. Any change in the
heritable traits within a
population across a
generation.
For example spots on the wings of a
butterfly,
Fur colour in mice, or

4. How did living things
evolved? Charles Darwin
theorized that all
life came from a
common ancestor
like a single celled
organism. As time
went on, life forms
became more
complex and
diverse.

5. Origin of the first cell(s).
Scientist believed that a chemical
evolution may have produced the
first cell. First, inorganic chemicals
reacted to produce small organic
molecules, which polymerized to
form macromolecules. With the
origination of the plasma
membrane, the first primitive cell
(a Protocell) evolved, and once this
could replicate, life began.

6. The Evolutionary Tree
Evolutionary tree is a branching
diagram or tree showing the
inferred evolutionary relationships
among various biological species.
The branch tips represent existing
species. The branches connect the
common ancestor, and the nodes
depict where one species diverged
into two or more species.

8. Evidence of Evolution
 Fossils are the remains and traces of past
life or any other direct evidence of past
life. Most fossils consist only of hard parts of
organisms, such as shells, bones, or teeth,
because these are usually preserved after
death.

9. SELECTIVE BREEDING OF
DOMESTICATED ANIMALS
These domesticated breeds have
been developed from wild
species, by selecting individuals
with desirable traits, and breeding
from them.

10. HOMOLOGOUS ANATOMICAL
STRUCTURES
 The fact that anatomical similarities exist
among organisms provides further support
for evolution.

12. Agents of evolutionary change
Because evolution is based on
changes in living organism that makes
them more complex and diverse,
scientists have discovered that there
are agents or factors that causes these
changes. These conditions are:
Mutations
Genetic Drift
Gene Flow and
Natural selection

13. Mutations are random alterations in
our genes, the result of genes
failing to copy themselves properly
or exposure to radiation or other
chemicals (called mutagens).

14. Genetic drift is a mechanism of
evolution that occurs by random
chance rather than natural
selection. In genetic drift, a
population experiences a change
in the frequency of a given allele,
prompted by random luck rather
than a need for adaptation

15. Gene flow is also called migration.
This is any movement of genes
from one population to another.
Gene flow includes lots of different
kinds of events, such as pollen
being blown to a new destination
or people moving to new cities or
countries.

16. Natural selection
Charles Darwin developed the theory that
evolution occurs as a result of natural
selection. It is the process by which some
individuals produce more offspring than
others. Hence to survive, it must compete for
food and a mate. The organisms that survive
is consider fit for the environment thus the
characteristics that helped this ‘fitness’ will
be more common in the next generation
than those of its less ‘fit’ relatives.

17. The Taxonomy of Living
Things
The taxonomy of living
things basically refers to
the classification of all
living things.

18. Why is it necessary to classify
living organism?
 It helps to identify different
organisms and place them in
their particular group.
It helps us to study them more
easily and systematically.

19. It highlights the relationship
between different organism
The characteristics of all the
members of a group can be
studied by studying the
characteristics of a few
members only.

20. Types of Classification
system
There are two (2) types of
classification system.
Artificial System –this system of
classification is based on
comparison of one or a few
characteristics of a group. By this
classification, different organisms
could be grouped together.

21. The natural system
This system of classification is
based on comparison of many
characteristics of a group. It
takes into account many
characters such as external
structure, internal structure,
growth, development,
reproduction.

22. Hierarchical Classification of
Organisms
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

23. So what are domains?
 “Domains” are the cell type that
an organism has. There are 3
domains:
Bacteria
Archaea
Eukaryote

24. Kingdoms
 There are five
kingdoms:
 Monera
 Protists
 Fungi
 Plants
 Animals

25. Group
Names
Humans House cat White oak Housefly
Domain Eukarya Eukarya Eukarya Eukarya
Kingdom Animalia Animalia Plant Animalia
Phylum Chordate Chordate Magnoliop
hyta
Arthropod
a
Class Mammal Mammal Magnoliopsi
da
Insect
Order Primates Carnivora Fagales Diptera
Family Hominidae Felidae Fagaceae Muscidae
Genus Homo Felis Quercus Musca
Species sapiens domestica Alba domestica

26. GENERAL PLAN OF CLASSIFICATION
All classifications involve systematic grouping of basic units.
• The basic unit of biological classification is species.
• A species refers to a group of organisms that closely resemble
each other and can reproduce among themselves.
• Similar species are grouped into a genus.
• Similar genera (plural of genus) are grouped into a family.
• Similar families are grouped into an order.
• Similar orders are grouped into a class.
• Similar classes are grouped into a phylum

27. Binomial Nomenclature
In binomial nomenclature, the name of an
organism is composed of two words in Latin. The
first word is the name of the genus and is called
the generic name. The second word refers to the
name of the species and is called the specific
name. The first letter of the generic name is
always written in capital letters whereas the first
letter of the specific name is written in small
letters. The scientific names are italicized in
printing and underlined while writing.
Example Homo sapiens
Musca domestica