Let us Pray…

What is Evolution?

Is a slow

process of change

by which organisms

have acquired their

distinguishing

characteristics; it

has been going on

since the Earth was

formed billions of

“Evolve” Means to Change Over

Time • The notion that

life on Earth has changed over time is quite old

• To be considered science, this notion requires

Is evolution a fact or a theory?

We could say that it is both.

It is a fact, for example,

that living organisms have

changed over time. These

changes, which include the

evolution of major groups of

plants and animals, are

documented in fossil records

and were recognized by the

Charles Darwin’s

On The Origin of

Species provided a

convincing theory as to

how these changes

occurred. In this

respect, evolution is

indeed a theory, a

collection of carefully

reasoned and tested

hypothesis about how

evolutionary change

occurs.

How about Natural Selection?

The theory that

states

that those organisms

best adapted to their

environment have

a better chance of

surviving and

reproducing.

Okay!!! Let’s have a Sojourn to

Galapagos Islands with Darwin…

Hooray!!!

THEORY OF

NATURAL

SELECTION

Charles Robert

Darwin (1809 - 1882)

proposed and formulated

the process of evolution

in his book, On The Origin

of Species by Means of

Natural Selection

published in 1859 after

taking trip around the

His theories

stated that common

descent does occur and

that natural selection

results in adaptation to

the environment.

Natural

Selection is the

mechanism he proposed

for how adaptation comes

about.

It is caused by

environmental selection of

The Voyage of the Beagle: Ports

of Call

Noted that

populations of

organisms

were slightly

different from

place to place

Each group

was modified

to their

specific

environment

The Galapagos

Archipelago

What did Darwin find at the Beagle?The finches on each island in the Galapagos

had different types of beaks.

What did Darwin find at the Beagle?The tortoises on each island in the Galapagos

had different types of shells.

With those

observations

Darwin found out

that:

1.Organisms had a common ancestor, but had adapted to

their particular environments and changed over time.

2. Darwin published his

Natural Selection• For natural selection to occur,

there must be at least two varieties of a species.

• For example: the peppered moth

Peppered Moths

• At the beginning of the Industrial Revolution in England, coal burning produced soot that covered the countryside in many areas

What do you think

happened?

Evolution/Natural Selection

• White moths became

easier to see, while

the black moths

became harder to

see. The black moths

were more likely to

survive and pass on

the gene for dark

color to their

offspring.

• Over time, the black

moths

Development of Evolutionary

TheoryDarwin Concluded:

• Physical traits and behaviors enable

organisms to survive and reproduce

(called Fitness )

• Fitness results from adaptations

–Structural (body structures)

–Behavioral (protection, predation,

mating)

–Functional (chemicals produced by

the organism that perform special

Let’s have a Review with Haik!!!

Group Activity

Directions:

Divide the class into two. Each

group will formulate a summary of

Darwin’s Natural Selection in a form of

news story and present it to the class

thru News Casting, Each group will

select at least 2 reporters to do the

news casting.

WILDCATS

NEWS

Charles Darwin’s Natural Selection!HEADLINES