Transcript Evolution

BIG IDEA:
THE ENVIRONMENT SELECTS THE TRAITS OF
ITS INHABITANTS.

Biogenesis:
› All living things come from other living things

Spontaneous Generation :
› States that life can come from nonliving matter

Evolution :
› the development of new types of organisms from
preexisting organisms over time

Natural Selection:
› Is the mechanism for “descent with
modification”

Adaption:
› A trait that makes an organism successful in its
environment
 EX:
 thicker fur coats in cold climates

Fitness:
› Is a measure of an individual’s hereditary
contribution to the next generation

Homologous Structure:
› structures that occur in different species and
originate from a common ancestor

Analogous Structure:
› Structures that are closely related but do not
derive from the same ancestor

Vestigial Structure:
› Structures that serve no function but that
resemble structures with functional roles

Fossil:
› Are the remains of an organism that died long
ago
› EX:
 Dinosaur bones

Control Group:
› the group that doesn’t change

Experimental Group
› the group that has the variable

A theory summarizes many hypotheses
that have been supported

It is accepted as long as there is NO
evidence to disagrees with it

So
› They can be disproven

15 billion years ago
› HUGE explosion that started the expansion of
the universe

This explosion  BIG BANG!!!!

It is thought that the explosion was more
inward

It laid for the foundation of the universe
A

piece of meat was left out.
The next day flies and maggots
were seen on the meat.
 Where
did the flies come from?
› The thought the meat.
Is
the idea that life can
arise from nonliving matter.

There is a “life force”

Francesco Redi

Lazzaro Spallanzani

Louis Pasteur
 1668
› Francesco Redi
 One
scientist that
performed an
experiment that
disproved
spontaneous
generation
Control
group:
› Put meat in a jar
uncovered.
Experimental group:
› Put meat in a jar covered.
He lets the jars sit out for a couple days
 Observes……

Control Group:
Flies
found
on the meat.
Experimental Group:
No
flies on
the meat.
Conclusion
› Flies do not come from the
meat.
 Italian
scientist
 1768
› Performed another
experiment that
disprove
spontaneous
generation
Control
Group:
› Boil broth
› Left flask open
Experimental Group:
› Boil broth
› Sealed flask
Control Group:
Experimental Group:
Control:
› Broth becomes cloudy
 bacteria present
Experimental:
› Broth remains clear
 NO bacteria
The bacteria came from
the air


French chemist

He disproved
spontaneous
generation

Invented the
Pasteurization
method
1862:
Boil broth in a curved-neck flask.

›
Curved-neck trapped large particles from
getting into the body of the flask.

Control
› The neck on the flask was not broken

Experimental 
› The neck on the flask was broken

After a year,
› Broth in the not broken neck of
flask  clear
› Broth in the broken neck of flask
 cloudy
Bacteria
came from the
outside air.
All
living things come from
the reproduction of other
living things.

It is the idea that new organisms come
from preexisting types of organisms.
Jean Baptiste Lamarck
 Charles Darwin



French Biologist
Famous for his
evolutionary theory of
inheritance
1809
 Two
Theories
1. Use and Disuse
2. Inheritance of Acquired
Characteristics
 Body
parts that are used more
grow stronger and bigger
 USE
 Body
parts that are NOT used
deteriorate
 DISUSE
 Physical
changed that occur in
an organism are inherited by their
offspring(s).

Giraffe’s neck
› They gets longer as it
stretches to reach food in
trees.
NO!!!!!!
Variations
that occur in the:
› GAMETES cells are passed to
offspring
› SOMATIC (body) cells are
NOT inherited

British Naturalist

Set sail on the HMS
Beagle

Famous for his studies
with finches on the
Galapagos Islands

“Father of Evolution”
Went to the
Galapagos Islands
 He observed
different types of
finches
 These observation
lead to him
developing his
theory of evolution

British Naturalist
 Co discover of natural
selection
 Wallace and Darwin
presented their ideas to
the public

› Darwinism
States:
1. Descent with modification
2.
Evolution occurs by the
process of natural
selection.
Decent of Modification
 Evolution
 Natural Selection
 Variation
 Adaptions
 “Survival of the Fittest”
 Fitness
 Speciation
 Specie


states evolution is the
development of new
organisms from preexisting
organisms over time.
 Over
production:
› In a population, more offspring
are produced than can survive.
 Competition
› Only some survive long enough
to reproduce.
 There
is variation within a
population
 these
variations are inherited.
 traits
that are favorable and
improve the organism’s ability
to function and reproduce.
 States
that survivors pass on
their variations.
 Therefore…..
 a larger proportion in the next
generation will have those
variations.

is a measure of an individual’s
genetic contribution to the
next generation.
Over
time, small changes
accumulate and
populations change.
a
group of organisms that can
mate and produce fertile
offspring.
 Organisms
constantly strive to
improve themselves and become
more advanced
 This
effort causes the most used
body structures to develop,
› while unused structures waste away
 AKA Used/Disused Theory
 Once
a structure is modified,
› It is inherited by the organism’s
offspring
 Think
about the muscles used
by a runner
 There
is always a variation
amongst a population.

Many variations are inherited
and passed on to offspring
 However,
 some are more favorable
 Improve organism’s survival in the
environment
 More
young are produced in
each generation than can survive
 Organisms
that survive and
reproduce are those with
favorable characteristics

He came to the same conclusions as
Darwin did
American
Evolutionist
He
came up with
Punctuated Evolution
› Which defies the known way
of evolution’s pace
 species
remain the same for
extended periods of time
› then small changes occur

States that for long periods of time, the
existing species didn’t change 
Equilibrium

Then, in relatively short periods of time,
there is an interruption in the equilibrium

New species emerge.

Evolution that occurs slowly
and continuously
throughout time

Lamarck’s Theory

Darwin’s Theory
 The
environment changes
Which creates a need for
organisms to change
 Organisms
development new
features which are passed
down to offspring
Newly
acquired traits
somehow get passed down
to offspring
New
species  eventually
evolves
Variations
are inherited
Environment:
› selects features survival
› eliminates others
Those
traits which:
› help survival tend to survive
› Those organisms have more
offspring
Therefore…..New
species
1.
2.
3.
4.
Fossil Evidence
Anatomy
Embryology
Molecular Evidence
 Fossils:
› remains/trances of
organisms that died
long ago
› They are often found
in strata
 Strata layered
rock
 If undisturbed,
›
›
the lowest stratum is the oldest
the highest stratum is the newest
 Relative Age:
›
is found by comparing ages of strata
 Absolute age
›
is found by using radiometric dating
• Fossil record
suggests that
different
species were
present in the
past than
today.

Gradualism
› Fossil record should
show many transitional
species,
 they DON’T

Punctuated Equilibrium
› Fossil records seem to
support this
› However, the mechanism
is uncertain

studies the parts or
structures of living
things.

Similar internal parts

Different function in different organisms

This suggest descended from COMMON
ANCESTORS

Ex:
›
›
›
›
Human arm
Cat leg
Whale fin
Bat wing
 Similar external form and
function
 Different internal forms and
function
 Suggests species came
from DIFFERENT ancestral
lines
 Ex:
›
›
›
Bat Wing
Bird Wing
Insect Wing

Is the study of embryos as
they develop

Similarities of the
development of embryos:
›
suggests that the species have a
common ancestor
Is when we analyze chemical
similarities between organisms
 Ex:

a. DNA Comparison
b. Protein Comparison

The more DNA is similar the CLOSER the
relationship between the organims

Amino acids
› The building blocks of proteins
Similarities of amino acids that make
proteins suggest a relationship between
organisms
 EX:

› In proteins the difference between amino
acids……
 Humans vs. monkeys  1 difference
 Human vs. pigs  10 differences