The document discusses several historical theories of evolution, including theories of special creation, spontaneous generation, transmutation, use and disuse, and need. It provides examples of how each theory attempted to explain observed phenomena like the development of long necks in giraffes and elongated bodies in snakes. However, these early theories were unable to fully explain the diversity of life and inheritance of traits between generations. The document introduces Charles Darwin's theory of natural selection as able to explain these aspects of evolution.

2.  Evolution is the change in
the inherited characteristics of biological
populations over
successive generations. Evolutionary
processes give rise to diversity at
every level of biological organization,
including species, individual
organisms and molecules such as DNA
and proteins.

3.  Theory of Special Creation
 Theory of Spontaneous
Generation
 Theories ofTransmutation or
Evolution

4.  Theory of Use and Disuse
 Theory of Need
 Theory of Inheritance of
Acquired Characteristics

5. • The vegetation on that time
was almost consumed
• the giraffe needs to stretch its
neck to reach those leaves on
the trees.
• Their neck often led to the
development of long necks due
to its need to reach for more
food
• Since the giraffe are already
long-necked, they will probably
give riser to long-necked giraffes

6. • Observed on the changes
in the body shape of a snake.
• Changes in land formation
occurred and snakes had to
pass through narrow places
• The snake had to crawl
because of its need and later
on transformed the body of
the snake to an elongated
form.

7. • The traits and
characteristics were
passed on its
offspring.
• The characteristics
are being inherited
by the present form
species.

8. • He wanted to test Lamarck’s
Theory on the Inheritance of
Acquired Characteristics
• He cut the tail of the mouse
and mated it with a long-
tailed mouse.
• He repeated the experiment
for 22 generations.
• On the 21st generation, all
the mice had long tails. this
experiment disproved the
theory of Lamarck

10.  It did not show the real meaning of
Transmutation
 It did not show the real meaning of
Speciation
 TheTheories did not account
Biodiversity

11. TheTheory of
NATURAL SELECTION