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NAME:________________________________________
Unit 4- Evolution
Evolution and Darwin
Evolution is surrounded by controversy -Why?
• People have __________________________________________
•
People don’t like the idea that “______________________________________”
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There is a lot more to evolutionary theory than ________________________________________.
The Camps surrounding Evolutionary Theory
• Creationists- believe a ____________________________________________ (God, Allah, Great
Spirit etc.) created everything as it is today
•
Intelligent Design-followers believe the living world is too complex for it to just happen. Some
______________________________________________ had to be behind making the blue prints.
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Evolutionists- believe organisms __________________________________ to their present forms.
What do you need to do to be successful with Unit #4?
• You do not have to ________________________________ Evolutionary Theory.
•
You only have to _______________________its principals and concepts that we learn in our
future lessons
Evolution is
• The ________________________________________________________________________ on
earth from it’s earliest forms to the vast diversity that characterizes it today.
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A change in the _________________________________________!!!!!!!!
Old Theories of Evolution
• Jean Baptiste Lamarck (early 1800’s) proposed: “The inheritance of acquired
characteristics”
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He proposed that by __________________________________________________
__________________________________________an individual tends to develop
certain characteristics, which it _________________________________ offspring
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“The Inheritance of Acquired Characteristics”
Example:
A giraffe ________________________________________________
because its ancestor stretched higher and higher into the trees to reach leaves,
and that the animal’s increasingly lengthened neck was passed
on ________________________________________________.
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Would these acquired characteristics get passed on to their offspring?
Of course not. The acquired characteristics ______________________________________
____________________________________cells.
Use and Disuse
-Fish in caves don’t use their eyes so they ________________________________r
-Elephants use their trunks a lot so they get longer
Although false, his theory ____________________________________________ to explain how
organisms adapted to their environment over time
.
Charles Darwin
• Influenced by Charles Lyell who published “Principles of Geology”.
•
This publication led Darwin to realize that natural forces gradually change
the Earth’s surface and that the forces of the _________________________
_____________________________.
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Darwin set sail on the _______________________________ (1831-1836)
to survey the south seas
(mainly South America and the ____________________________________) to collect plants
and animals.
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On the Galapagos Islands, Darwin observed ___________________ that lived nowhere else in
the world.
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These observations led ______________________________to write a book.
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Wrote in 1859:
“On the ______________________________________by Means of
Natural Selection”
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Two main points:
1.
Species were not ____________________________________________form, but
evolved from ancestral species.
2.
Proposed a mechanism for evolution: __________________________________
Natural Selection
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Individuals with ___________________________________________________ are more likely
to leave more offspring _________________________________________ for their environment.
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Also known as “Differential Reproduction”
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Example:
English peppered moth (Biston betularia)
- light and ____________________________________
Artificial Selection
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The selective breeding of domesticated plants and animals by man.
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Selective Breeding is also called
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Question:
What’s the ancestor of the domesticated dog? Dog Genus and Species______________________
Answer: _________________
Genus and Species___________________________
Both of these trees are in my yard and are the same species (Thuja occidentalis)
Which one looks better? Why?_____________________________________________________
______________________________________________________________________________
They are both in the same _________________________________ (water, sun, nutrients are the
same). Why do they look so different? _______________________________________________
Which one do you think humans selected desirable traits in deliberate plant crosses? A or B
Darwin is the founder of Modern Evolutionary Theory
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Science attempts to:
-Describe events based on phenomena _______________________________________
-Explain events _______________________ terms of events we can observe today
-Make predictions about __________________________________________
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A Theory such as Evolution Theory is supported by a lot of data collected by _______________
_________________
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Theories can be ______________ (i.e.Lamarck) or _____________ as scientist get new
information
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Theories can’t be proven with ______________________________ (i.e.-Gravitational Theory,
Cell Theory, Contagious Disease, Genetics)
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Evolution is ___________________________________________________ life on earth from it’s
earliest forms to the vast diversity that characterizes it today.
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Evolution results in a change in ____________________________!!!!!!!!
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Darwin _________________________________________ that humans originated from monkeys.
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Darwin claimed that humans and monkeys (well, apes really) have a _______________________.
______________________________That is, they originated from the same species many years
ago
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Evolution is the process of change in a population __________________________________.
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Existing life forms have evolved _________________________________________.
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Evolutionary theory is a unifying principle ___________________________________________.
( Genetics, Biochemistry, Anatomy, Physiology etc.)
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Evolution Theory provides an explanation for the _____________________/ similarities in
_________________________________, function, and behavior among life forms.
Evidence of Evolution
Cladograms or phylogenetic trees are graphic representations
of ___________________________________________.
Common Ancestor (draw arrow)
1.
Geographical distribution of species.
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Alfred Russell Wallace was also known as the "father of biogeography.
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______________________________________________________-the study of the past and
present geographical distribution of organisms.
Reproductive Isolationprevents _______________________
on the other islands. Two
populations develop
______________________.
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Evidence of Evolution (continued)
2. Fossil Record:
Fossils and the order in which they appear in layers of sedimentary rock (strongest
evidence).
Evolution of the horse
What changes do you notice in moving from
the bottom to the top?
Increase _____________________________
Changes in the ________________________
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Relative Dating-In relative dating, something is determined to be _________________________
_______________________than something else by using the laws of s_____________________.
-Layers (strata) close to the surface are ________________________
-Deeper Layers contain the __________________
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Absolute Dating-dating determines the actual __________________________
-One of the most widely used and well-known absolute dating techniques is _______________
dating, which is used to date ___________________ remains.
3. Taxonomy-classification of organisms ________________________________________ based on
their physical characteristics and presumed natural relationships (remember Did King Philip Come
Over………..?)
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In 1735, Carolus _____________________________published a book in which he outlined his
scheme for classifying organisms and is still in use today
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The Linnaean system uses two Latin name categories,
________________________________and ________________________ , to designate each type
of organism.
4. Homologous structures: Structures that are
similar because of ______________________________
__________________________(comparative anatomy)
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Homologous Structures- structures shared by related species because they have been
inherited _____________________________________. (flipper of a whale and hand of a human)
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Analogous Structures- Analogous structures ________________________________________
_____________________________________in different species but is not a result of sharing a
common ancestor. (wing of a butterfly and wing of a bird)
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Vestigial Structures- organ or structure that once was useful in an animal’s evolutionary
past, but that ________________________________ or very close to useless.
5. Comparative embryology:
Study of structures that __________________________________
___________________development. Any ideas on why they are
similar?
Scientist believe that ____________________________
______________________result in death or spontaneous
_____________.
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NATURAL SELECTION
-There is ________________________________ involved in Natural selection
-There are __________________________________ in Natural Selection
-It is all about the genes an ______________________________________________________________
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1. Overproduction -- Within a population, more offspring are born than can _________________
______________________________.
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2. Competition – Over production results in struggle for space, water, food, light, mates or other
limited resources
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3. Variations-Members of populations ______________________________________________
(differences in traits) that make certain individuals better adapted to survive
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4. Natural Selection-Some variations are more helpful than others, there is a natural selection
_____________________________________________________________________________.
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5. Organisms that can’t adapt DIE and some populations ________________________________.
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6. Survival of the Fittest -- The individuals who _______________________________________.
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7. Inheritance of variations-Organisms with helpful variations survive and __________________
___________________________________ REPRODUCE.
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8. The best adapted individuals ________________ and _________________________, passing
on the favorable variations to their offspring (& population ). These changes improve the
__________________________________ (population) in its environment
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9. If an organism does not live long enough to reproduce it has ___________________________
________________________________EVOLUTION OF THE POPULATION.
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10. Individuals ___________________________, only populations can evolve. (make sense
because genes have to be passed on to offspring for evolution to take place.
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11. Evolution of New Species-Over long periods of time, so many variations may accumulate that
a population may become a new species. This process is called Speciation
Some Sources of Variation in Modern Natural Selection Theory
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The genetic basis for variation within a species is provided by
_____________________ and _____________________________.
(crossing over and recombination)
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2. Mutations are spontaneous and provide ______________________________ for evolution.
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Modern Natural Selection Theory
•
1.) All species have ___________________________________________ in numbers.
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2.) There is a ___________________________________________ for any species. Species tend
to make too _____________________________ for these resources.
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3.) Species will show genetic variability due to _________________________, crossing over, and
_____________________________________________ (during fertilization) of genes.
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4.) The scarce finite resources of the environment will select those offspring_________________
_____________________________________ and less fit offspring may die.
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5.) Variations within a species _____________________________________________________
_______________________________some members of the species will survive under changed
environmental conditions.
-Traits which are ______________________________________________________ of an
organism in a particular environment tend to be retained and passed on, and therefore,
increase in ____________________________________________________ population.
-Traits which have a ____________________________________________________ to
organisms tend to diminish in frequency from generation to generation.
-If __________________________________________________________________,
traits that were formerly associated with a low survival value may, in a changed
environment, have greater ___________________________________________________
_______________________accordingly.
Population Genetics
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The science of _____________________________________________ population.
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Hardy-Weinberg equation is important and will be __________________________________.
Vocabulary
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Population- A localized group of individuals belonging _______________________________.
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Species- A group of populations whose individuals have the ___________________________
and produce ___________________________________________________________________.
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Gene Pool-The total collection of _____________________________________ at any one
time.
Hardy-Weinberg Principle
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The concept that the ________________________________________________________ that
occur during sexual reproduction, _______________________________________, cannot change
the overall genetic makeup of a population
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This principle will be maintained in nature only if all five of the following conditions are met:
1.
Very _______________________________________________
2.
Isolation from other ____________________________________________
3.
No net __________________________________
4.
______________________________ mating
5.
No natural _________________________________________
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Remember: If these conditions are met, the population is at _________________________.
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This means “No Change” or “________________________________________”.
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The Hardy–Weinberg equilibrium is impossible in nature. Genetic equilibrium is an ideal state
that provides a baseline to measure genetic change against.
Macroevolution
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The origin of taxonomic groups ________________________________________________ level.
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Involves _____________________________ periods of time
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____________________________ in organism
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Scientists can see changes in fossils of __________________________________________
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Example: Sea cow (manatee) ancestor with legs
Microevolution
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A change in a ____________________________________ over a secession of generations.
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Evolutionary changes in species over _____________________________________________ of
geological time.
Five Mechanisms of Microevolution
1. Genetic drift-Change in the gene pool of a small population ________________________
__________________________________________.

Bottleneck effect
a. Genetic drift (reduction of alleles in a population) resulting from a
disaster that __________________________________________.
( results are similar to inbreeding)
b. Examples of disasters:
1.
Earthquakes
2.
Volcano’s
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3.

Founder effect

Genetic drift
Droughts
____________________________________________________________ of a new
location by a small number of individuals.

Founder populations are often
____________________________________________________

Results in _____________________________________ of the gene pool.

Mutiny on the Bounty (1789): Population of 9 mutineers, 8-9 Tahitian females and 6
Tahitian males to uninhabited Pitcairn Island.
2. Gene Flow: The gain or loss of alleles from a population by the movement of individuals
or gametes.
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Immigration-movement in
–
Emigration-movement out
3. Mutation: Change in an organism’s DNA that creates a new allele.
4. Non-random mating: The selection of mates other than by chance.
5. Natural selection: Differential reproduction- competition for mates, those best adapted
survive and produce more offspring.
Modes of Action
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Natural selection has three modes of action:
1.
Stabilizing selection
2.
Directional selection
3.
Diversifying selection
Number
of individuals
Small
Large
Size of individuals
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1. Stabilizing Selection-
Acts upon extremes and favors the intermediate.
Number
of individuals
Small
Large
Size of individuals
2.
Directional Selection- Favors variants of one extreme.
Small
Large
Size of individuals
3.
Diversifying Selection- Favors variants of opposite extremes
Small
Large
Size of individuals
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Speciation- The evolution ___________________________________________________.
Reproductive Barriers
• Any mechanism that ____________________________________________________ from
producing fertile and/or viable hybrid offspring.
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Different species most likely have different _________________________________________
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Two barriers:
1.
1.
Pre-zygotic __________________________________
2.
Post-___________________________ barriers
Pre-zygotic Barriers
a. Temporal isolation: Breeding occurs at different times for __________________________
_______________________________________________________________.
b. Habitat isolation: Species breed in different ____________________________________.
c. Behavioral isolation: Little or no ___________________________________ between
species.
d. Mechanical isolation: Structural differences prevent ______________________________.
e. Gametic isolation: Gametes die before uniting with gametes of other species, or gametes
_________________________________________.
2.
Post-zygotic Barriers
a. Hybrid inviability: ___________________________ fail to develop or fail to reach sexual
maturity.
b. Hybrid sterility: Hybrid fails to produce _________________________.
c. Hybrid breakdown: Offspring of hybrids are __________________________.
Interesting but not Fertile
The liger is a hybrid cross between a ______________________ lionl(Panthera leo) and a
______________________tiger(Panthera tigris)
The _______________________________ is a cross between a male tiger (Panthera tigris) and
a female lion(Panthera leo),
What cross is made to produce a mule?__________________________________________
Allopatric Speciation
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Induced when the ancestral population becomes separated by a geographical barrier.
The "Albert" squirrel primarily lives at the ________________________________.
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The ________________________________squirrel looks very similar but without the
reddish back and only live at the North Rim.
Adaptive Radiation
Emergence of numerous species from a common ancestor introduced to new and diverse
environments
Interpretations of Speciation
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Two theories:
1.
Gradualist Model- ___________________ changes in species overtime.
2.
Punctuated Equilibrium: Evolution occurs in spurts of relatively
_________________________change.
Coevolution
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Evolutionary change, in which one species act as a ____________________________________
_______________________________species, inducing adaptations that in turn act as selective
force on the first species.
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Example:
1.
Golden Rod Plant and _________________________________________
2.
Humming birds and plants with flowers with long tubes
-What beak size would you expect in humming birds if the flowers were longer in
length?_________________________________________
POPULATIONS
•
Population-all of the individuals of a species that live together in ______________________ at
one time.
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Demography-the ______________________________________ of populations. It is used to
predict how the size of a population will change.
1. Population size
 is the number of individuals in a _________________________.
 has an important effect on the ability of the population to survive.
 A __________________________________________ is more likely to become extinct:
 in the case of random events or natural disaster
 due to _________________________________ where the population is more genetically
alike. Recessive traits are more likely to appear.
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 with reduced ____________________________________ it is harder to adapt to
changes.
2. Population density
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the number of individuals in a given area.
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if _________________________________________________ are too far apart they may only
rarely encounter one another resulting in little reproduction.
Population size is limited by:
density-dependent factors
density-independent factors
-disease
Volcanic _______________
-______________________
-T______________________
-Predators
-____________________________
-P________________________
-Floods
-__________________________
-Dr____________________________
-Crowding
-Chemical_______________________
-Major ______________________destruction
Most are ___________________factors
3. Dispersion
 the way in which the individuals are located
Random
Uniform
Clumped
PREDICTING POPULATION GROWTH

Model:

A hypothetical population that has key characteristics of the real population being studied.

Used by demographers to predict how a ______________________________________________.

Nearly all populations will tend to grow __________________________________ as long as
there are resources available.
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
Two of the most basic factors that affect the rate of population growth are the _____________,
__________________________and the death rate.

r(rate of growth) = birth rate – ________________________ rate

Exponential growth curve: population growth plotted against time.
 As a population gets larger, it also _____________________________ rate.
 This is the maximum population growth under ideal circumstances.
 Includes plenty of room for each member, unlimited resources (food, water) and no
hindrances (predators).
 FACT: No population exhibits this type of growth for long.

Logistic model: This model accounts for the declining resources available to populations as they
grow.
 It assumes the birth and death rates are not constant.
 As the population grows, births decline and _______________________________.
 Eventually birth = death so the population ________________________________.
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Carrying capacity (K): The number of organisms of one species that an environment can support
indefinitely.
The Exponential curve (also known as
a J-curve) occurs when there is no
_______________________________
_______________________________
The Logistic curve (also known as an S-curve)
shows the effect of a _____________________
___________________________________(in
this case the carrying capacity of the
environment).
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POPULATION GROWTH STRATEGIES
There are 2 ways a population can prosper:
1. Depends on the rate of growth (r)
2. Influenced by the carrying capacity (K)
r-strategists: characterized by exponential growth, which results in temporarily large populations,
followed by sudden crashes in population size. Ex. Insects, bacteria, some plants
–
live in unpredictable and rapidly changing environments
–
Reproduce quickly when conditions are favorable
–
Many offspring: small, mature rapidly, no parental care
–
r = rate of growth
K-strategists: characterized by a high degree of specialization.
Ex. Trees, whales, tigers, etc.
–
Live in stable and predictable environments
–
Can compete effectively
–
Reproduce late in life
–
Few offspring: large, mature slowly,
often much parental care
–
K = carrying capacity
Human Populations:
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K- strategist characteristics
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Man has learned to expand the carrying capacity
of his environment by increasing food supply,
combating pests and curing diseases.
•
Can Earth support this increase?
•
Damage to the planet will eventually reduce the carrying capacity for humanity and slow the
growth of the human population.
How do Humans and other organisms fight off disease?
Tears-_____________
saliva antibacterial
enzymes
Skin-______________
Stomach acids
Mucus linings
“Good “Gut Bacteria
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Pathogens- any disease-producing agent (especially a virus or bacterium or other microorganism)
•
Bacteria (prokaryotes-_________________________________________________
_______________________________.
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Virus-mostly just ______________________________________
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fungi,
•
protozoa,
•
Parasite
Second lines of defence
•
Involves __________________________________
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Non-specific response
–
•
invading pathogens are targeted by _____________________________
Specific response
–
lymphocytes produce chemicals called __________________ that target specific
pathogens
Phagocytes are the white blood cells that protect the body by ingesting harmful foreign particles
such as ____________________________
Evidence of phagocytosis are dead white blood cells that we call pus.
•
Stages in phagocytosis
1. Phagocyte detects chemicals released (antigens) by a foreign intruder (e.g. bacteria)
2. Phagocyte moves up the __________________________________________ towards the
intruder
3. The phagocyte adheres to the foreign cell and ____________________________ it in a
vacuole by an infolding of the cell membrane.
4. Lysosomes (organelles which are rich in digestive enzymes & found in the phagocytes
cytoplasm) fuse with the vacuole & release their contents into it.
5. The _______________________________________________________________, and
the breakdown products are absorbed by the phagocyte.

During infection, hundreds of _____________________________________ are needed.

Pus is dead bacteria and phagocytes!
Lymphocytes

Provide a specific immune response to infectious diseases.
There are 2 types: - T-cells
- B-cells
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They produce antibodies in response to an antigen (An antigen _______________________
__________________________________________ the immune system)
•
all cells have surface markers called _________________________________________________.
•
body can recognise these as self or ________________________________ (foreign)
•
This comes into play with pathogens and organ transplants
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Lymphocytes detect presence of foreign antigens
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Stimulated to produce __________________________________ called antibodies.
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__________________combine with their specific antigen (_______________________________)
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Can be natural or _______________________________
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We can ____________________________________ to diseases by receiving ________________
HOW DID LIFE ON EARTH BEGIN?
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Earth’s early atmosphere probably contained hydrogen, cyanide, __________________________,
carbon monoxide, ________________________________, hydrogen sulfide and Water
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The early earth was much _____________________________ than it is now
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About 4 billion years ago the earth ____________________________enough to allow solid rocks
to form
ORIGIN OF LIFE
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1.) 1.) 3 to 4 billion years ago -- it is thought the first primitive single-celled life appeared on
earth in the water
•
2.) Heterotroph Hypothesis-proposes that the first living organisms were heterotrophs and did
not make their own food.
•
3.) These original ______________________organisms added carbon dioxide to the environment.
•
4.) Some autotrophs evolved a means of using carbon dioxide to do _______________________
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5. Autotrophic activity added free oxygen to the atmosphere.
-Some autotrophs and heterotrophs evolved mechanisms by which they used this oxygen to
derive their ______________________________. (aerobic respiration)
•
6. About a billion years ago, increasingly ________________________ multicellular organisms
began to evolve.
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7. The process of evolution took it from there.
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8. The great diversity of organisms is the result of billions of years of evolution that has filled
available ___________________________________________________________.
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The Miller–Urey experiment
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Was an experiment that simulated hypothetical conditions
thought
at the time to be present on the earth
•
Specifically, the experiment tested the hypothesis
that conditions on the primitive Earth favored chemical reactions
that synthesized _______________________ from inorganic
_________________________________.
•
Considered to be the ________________ on the origin of life.
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Was conducted in 1952 and __________________________________
_________________________________________!!!!!!!!!
(remember AA are the building blocks of protein
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In 2008, a re-analysis of Miller's archived solutions from the original experiments showed that
________________________________________________________________________amino
rather than 5 were actually created in one of the apparatus used.
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Interesting- Scientists repeat experiments
That is the end of the unit on evolution
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I truly hope that you have learned a lot about evolution
(__________________________________________) in the past few weeks
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Hopefully you have more information stored on your hard drive than just……
______________________________________________________

Some people never open their minds to new information and let go of incorrect information