Download UNIT B: EVOLUTION

Messana
 Evolution Movie Clip
SECTION #1B:
Unicellular:
Single–cell; 1 cell
Multicellular:
2 or more cells
Mammals:
Ex: Bacteria
Ex: Algae
Mass Extinction
 When a large # of species DIE out suddenly
 2 Major Ones:
 1) Permian- 250 million yrs ago (end of
Paleozoic Era) 90% of OCEAN LIFE died out
….the LARGEST MASS EXTINCTION!!
 2) Cretaceous - 65 million yrs ago (end of
Mesozoic Era) Dinosaurs became extinct
Section #2:
 BIOLOGICAL EVOLUTION – Process
through which SPECIES CHANGE over
time due to a CHANGE IN GENETIC
MATERIAL that is passed through
GENERATIONS.
 Theory of Evolution
 1st Life with David
EARLY IDEAS:
LAMARCK: (p 18B)
 French
 Animals ACQUIRED traits
during their lifetime and
passed them on to their
OFFSPRING
 EX:
DARWIN: (p 19B)
 British
 NATURAL SELECTION –
members of a species that are
BEST SUITED to the
ENVIRONMENT (nature) will
survive & reproduce.
SURVIVAL of the FITTEST!
 4 principles to support
 EX:
 Beaks of Finches
(Galapagos Islands)
“Fathers of Evolution”…
Alfred Russel Wallace & Charles
Darwin
Voyage of Beagle
 Dates: February 12th, 1831
 Captain: Charles Darwin
 Ship: H.M.S. Beagle
 Destination: Voyage around the world.
 Findings: evidence to propose a revolutionary
hypothesis about how life changes over time
Vogage route
Flip paper…..
DARWIN’S 4 PRINCIPLES
 OVERPRODUCTION:
 When plants or animals REPRODUCE, it makes
MORE OFFSPRING than actually survive &
reproduce EX: fish & turtle eggs
 Overproduction
VARIATION
 There are NATURALLY occurring differences in
TRAITS due to different GENETIC MATERIALS or
due to MUTATIONS-this is the PHENOTYPE of the
organism (HOW it LOOKS on the outside.
 Variations get “passed on”
 EX: BROWN vs BLUE eyes
MORE VARIATION…
 EX:
 NEMO had a short fin
 NO 2 zebras have the same STRIPE pattern
DARWIN’S PRINCIPLES (CONT.)
ADAPTATION:
INHERITED TRAIT that gives an
organism an “A”dvantage” in
its environment over other
members.
EX: Move faster (cheetah);
blend in (lions); camouflage
(chameleon); shape of tail fin
(fish)
SELECTION:
Organisms with an
ADAPTATION will SURVIVE &
REPRODUCE and PASS ON
the ADAPTATION “SURVIVAL
OF THE FITTEST!”
ADAPTATION
– “Inherited” trait that gives an organism an
ADVANTAGE in its particular environment over
other members of the group; become more
common from one GENERATION to the next!
EX:
- Fish with curved tail swim faster (speed)
- White fur rabbits blend in to snow better in arctic climates
(camouflage)
- Birds with stronger beaks can get food better (feeding)
- Bears can hibernate when their food source is scarce
- Beetle with horns can fight off beetle without horns
(defense)
SPECIATION & ISOLATION
Evolution of a NEW
SPECIES from an old
species, due to
ENVIRONMENTAL
CHANGE
“SPECIATION is due to
ISOLATION!!!
A1
A2
2 populations of SAME
SPECIES separated;
can’t reproduce;
differing mutations
occur; each evolves – 2
DIFFERENT SPECIES
“ISOLATION causes
SPECIATION”
Over time…VARIATIONS that
are BENEFICIAL will
ACCUMULATE & eventually
become ENTIRELY
DIFFERENT ORGANISM!! :0
Is ALLLLL Evolution NATURAL?
 NOOOOOOO!!!
Artificial Selection (also known as
“SELECTIVE BREEDING” is the breeding of
certain traits (better traits) over other
traits.
For example, breeding a good male horse
with excellent racing qualities with a healthy
female horse so that the offspring will have
the desired traits such as the racing qualities.
Another example is breeding good size fruits
or vegetable together to keep on getting the
good size.
Human who wants 2 fly
Problem: NO wings!!!
Plane…..with wings…..
Adaptation: non winged human
jumps from winged vehicle
And……FLIES … WHOOP WHOOP!!
Adaptation Activity
Will YOU survive?????
https://www.youtub
e.com/watch?v=ZBR2G
-iI3-I
I Will Survive!
New Section of NOTES….
Evidence for Evolution:
 1) Fossil Record
 2) Biological Evidence(the study of Biological
Classification is TAXONOMY):
A.)Homologous Structures = similar structure with
different function, means common ancestry (Ex:
forelimbs)
B.)Analogous Structures = similar function, but not
from common ancestor
C)Vestigial Organ = organ or structure used in an
ancestor, still present but not used in the evolved
organism
(Ex: leg bones in whales, appendix in humans)
Homologous Structures
Vestigial Organs
Evidence of Evolution:
Fossils
Fossils – show change in a single
species over time or similarities
between species
Evolution of the Modern Horse
Evidence of Evolution: Comparative
Anatomy
Analogous Structures – different
anatomical structure but similar
function that arise from common
environmental demands
 Human Vestigial Organs
3)GENETIC/DEVELOPMENTAL
EVIDENCE
A) Similarities in
embryology
B)Matching gene/DNA
sequences
Evidence of Evolution:
Molecular Biology
Molecular Biology - the genetic structure of an
organism
 The key to understanding how traits are passed
from one generation to the next is DNA analysis
 Scientists can tell how closely related organisms are
by studying their DNA
 There does not have to be that much of a difference
in a gene sequence to be a different organism!
Evidence of Evolution: Embryology
Embryology – shows similar
developmental stages amongst
different species
Similarities in Embryos
 Humans Speeding Up Evolution
Evolutionary Trees
 How do we represent this relationship?
Evolutionary Tree –
also known as a
phylogenetic tree; it is
like a family tree, but it
shows the evolutionary
relationships between
species branching back
to common ancestors.
Coevolution
Coevolution – when 2 (or more)
organisms or things affect each other’s
evolution/evolve together dependent on
each other
Genotype vs Phenotype
 Genotype: Set of GENES responsible for traits
within you (come from your ancestors …let’s
hope your ancestors are….CUTE, FUNY, SMART,
ATHLETIC, MUSICALLY INCLINED…
 SORRY…for some of you!!  :0 ..LOL!!
 Phenotype: the PHYSICAL EXPRESSION of those
traits (what you can see!! …how CUTE you ALL
are!! 
 Phenotypes
 Homologous/Vestigial Structures
Example
of
Evolution
 So how do animals and plants adapt to their
environment over time?
 Elephant Adaptation Video- s
 how
https://www.youtube.com/watch?v=CXcRw6Piaj8
 htthttps://www.youtube.com/watch?v=CXcRw6Piaj8ps://ww
w.youtube.com/watch?v=CXcRw6Piaj8w evolution of the
Earth affects the evolution of a species
http://player.discoveryeducation.com/index.cfm?guidAssetId=0B5B2
92A-983E-4327-A27DB647383BF293&blnFromSearch=1&productcode=US
Which Brings
UsSelection
Back To…
Natural
Or
“Survival of the Fittest”
What does “Survival of the Fittest” really
mean?
In the next few scenarios,describethe
phenotype that would most likely be
“selected” to survive…
WHITE Boards…Marker…Sock… READY!!
Survival
of the Fittest
Scenario 1: Drought
- There has been a drought and all of the grass has
dried up and died first, but the leaves on bushes
and trees are slower to die…who survives the
longest?
A. Animals with short legs but long necks
B. Animals with long legs, but short necks
C. Animals with both long legs and long necks
D. Animals with both short legs and short necks
Survival of the Fittest
Scenario 2: Predator is Approaching
- A predator is approaching the herd, but
is not hunting yet…who in the herd will
know sooner and therefore have a
better chance to escape?
Survival of the Fittest
Scenario 3: Predator Fight
- A predator has arrived. It is too late to
run away or hide, the animals must
fight off the predator…who has the best
chance at fighting?
Survival of the Fittest
Scenario 4: Blizzard
- The weather becomes very cold. There
is a blizzard and the land is covered in
snow…who survives?
Survival of the Fittest
Scenario 5: Volcanic Eruption
- There has been a volcanic eruption.
Lava flows down the mountain onto
the plains and kills anything in its
path…who will make it?