Download Evolution

Evolution
The Genetic Change in a
population (Species) Over Time
Acceptance of Evolution
Minnesota / North Carolina
 Minnesota
 Presence
of herbivores (molluscs such as
snails, slugs)
 smaller population, not present in winter
 North
Carolina
 larger, more active population, present all
year
UNLUCKY CLOVER

Some variants of white clover produce cyanide (CN), which is
a powerful poison. Two gene products are required to
produce active cyanide. One gene encodes an inactive
cyanide-sugar complex that is stored in the plant cell’s
cytoplasm. " Another gene encodes for an enzyme that
cleaves the sugar to activate the cyanide.
 “This enzyme is stored in the cell wall. In general, striped
clover contains cyanide; plain clover does not.
Variation
 Meiosis
 Populations
tend to over reproduce more
offspring
 No two are exactly alike
 Competition for resources (struggle)
 Those that survive (‘good genes’) with
those genetic (structures) adaptations,
mate and pass on thoes successful genes.
Where did all the variation come
from?
 Mimicry:
Disguise your self and possibly
increase your life span.
–look like your poison
 Mullerian –everyone is poison and looks
like it.
 Look like something uneatable
 Startle your enemy
 Batesian
Which one is poisonous?
Do they both sting?
Which one would make him do
this?
What are these sensory hairs used
for?
Coloration
When these eyes are closed, what
do I resemble and why?
Need I say more?
History of life on earth
Charles Darwin Packet pg

Darwin’s ideas ion Natural Selection




Populations tend to over produce
No two individuals are genetically the
same
‘struggle for survival’ organisms with
favorable alleles usually have a higher
survival and reproductive success rate
These organisms who survive and mate
produce offspring similar to the parents
with similar allele frequencies.
Galapagos
Jean B. Lamarck Packet

Proposed that individual efforts during the
lifetime of the organisms were the main
mechanism driving species to adaptation,
as they supposedly would acquire
characteristic changes and pass them on
to offspring. Use and Disuse!
Lamarck vs Darwin
Species Concept Packet pg 3
 “species
are groups of interbreeding
natural populations that are reproductively
isolated from other such groups." and
they produce offspring that can also
reproduce successfully.

Fossil Record
Indirect forms of evolution.
Packet pg

Fossils- any sign of
earlier life usually laid
down in sedimentary
rock. Types: castings,
impressions,
replacements.
Half life
 Rate
of decay for
a radioactive
Substances (isotopes
Differ in # of neutrons))
EvolutionaryTransitions

Archaeopteryx- fossil
transitional between
dinosaurs and birds
Analogous structures(write on the bottom of the fossil page)
 Different
structures, different ancestry but
the same function. (convergent Evolution)
Homologous Structuressame structures, common ancestor
but a different function pg 19
Vestigial Structures
Why did our hair evolve?
Embryo Development
Comparative biochemistry DNA
sequences page 19 part c
 classification
DNA sequences.mov
 Genetic evolution
Direct Evidence of Evolution
 Microevolution
pg
Divergent evolution and speciation
pg
 Sticklebacks
 Natures
camo
Industrial Melanism.

IndustrialMelanism.M
PG
 Peppered moth
Natural Selection
Natural Selection
Adaptation
Adaptation
 Body
size and coloration
Selection in populations Pg 21
Balancing selection
sickle cell anemia
Ecological Races (race circle)
 Rat
Snake
 Race circles salamander
Allopatric & Sympatric speciation
Isolation Mechanisms
Geographical/ Barriers
Reproductive isolation (structural)