In your notes, compare the two pictures. List at
least three similarities and at
least three differences
The change of a species over time….
Millions of years
Changes in structure, function and behavior
Theory: An idea Theory: An idea which is which is
supported by supported by extensive, extensive, repeated repeated
experiments, experiments, but not proven but not proven
as law.as law.Why Why isn’tisn’t evolution evolution a law?a law?
Limited access to Limited access to the pastthe past
Present day species developed
(evolved) from earlier distinctly
DIFFERENT species.
The “evolution” of Evolutionary Theories
1.) Lamarck’s Theory: Stated that
structures appear because they are
needed, Called the theory of
Use & Disuse ex. Longer necks in giraffes
Weismann
DISPROVED the theory that stated that acquired traits can be passed on
to the next generation.
Charles Darwin
“The Father of Evolution”
80
70
6 0
5 0
40
30
20
10
E Q U A TO R
20
30
40
50
6 0
70
80
30
40
5 0
6 0
70
80
20
10 10
30
40
50
60
70
80
80
7 0
6 0
5 0
40
3 0
2 0
1 0
3 0
T R OPIC OF C AN C ER
40
5 0
6 0
7 0
80 80
7 0
6 0
50
40
30
20
1 0
EQUATOR
T R OPIC OF C AN C ER
T R OPIC OF C APR IC OR N T ROP OF CAPRICORN
10
20
30 30
40 40
50 5 0
60 60
70 70
80 80 80
70
60
5 0
40
30
2 0
10
30
40
5 0
6 0
70
80 80
70
60
5 0
40
30
2 0
10
AUSTRALIA
A S I A
A F R I C A
E U R
O P
E
G RE E NLA ND
GREENLAND
NORTHA M E RICA
A NTA RCTICA
S OUTHAM ERICA
P A C I F I C
O C E A N
O C
E A N
I N D I A NO C E A N
P A C IF IC O CEAN
A T L A N T I C
HOW DID DARWIN START?
GALAPAGOS ISLANDS
1859 wrote book titled
“Origin of the Species”Key Concepts
1. Species present now were not created in
present forms instead they evolved from ancestral species
2. Natural Selection: 2. Natural Selection: causes evolutioncauses evolution
States that only those organisms containing the best variations can survive and reproduce in a
given environment
Adaptations • Inherited trait
• Improves an organisms chance of survival
Ex: Camouflage
Individuals who
survive are the ones
best adapted to
exist in their
environment
Formation of a new species
due to favorable
adaptations gradually
accumulating, while
unfavorable adaptations
gradually disappear
Any organisms which can:1. Interbreed2. Produce fertile offspring
3. Under natural conditions
Darwin observed 13 species of
finches on the Galápagos Islands that were similar except for
differences in body size,
beak shape, and eating
habits.
Noticed that all finches were similar to 1
finch he saw on the South
American coast
Darwin reasoned that the Galápagos finches
must have had to compete for food.
Finches with certain beak
shapes that let them eat food
survived longer & reproduced
more than finches without
those beak shapes
A person has been arrested on the charge that he robbed $50,000
from the First City National Bank last night.
What must the district attorney do to prove that this man is the robber?
Is the sum total of all the
fossils discovered and undiscovered
and their placement in sedimentary rock layers
Forms of Evidence
are the mineralized or
otherwise preserved remains or
traces (such as footprints) of
animals, plants, and other organisms
A. Fossils
is the study of similarities
and differences in the anatomy of organisms.
Structure and form
A. HOMOLOGOUS STRUCTURES
When body parts look similar in different species but do not perform the same function.
An example is the forelimb
structure shared by cats
and whales.
anatomy
whose bones are they?
are evidence that a common ancestor
exists for the organisms being
studied
Homologous Structures
Structures that are different but serve the same or similar purposes
An example is the torpedo body shape of porpoises and sharks
B. Analogous Structures
describes homologous traits of organisms which have lost all or most of their original function in a species through evolution
c. VESTIGIAL STRUCTURES
study of comparative
developmental anatomy
is the study of differences in
chemical components
among species
Examples:Hemoglobin,
DNA,Chromosomes
IS THE STUDY OF DIFFERENCES IN
CELL STRUCTURE, COMPOSTION AND
FUNCTION