Evolution: Chapters 10-12
2015
Intro to Evolution Activity – “Change by Chance?”
Diversity of Life
Evolution: Change over _______________
Theory: a well supported testable __________________ of ____________________that has occurred in
the natural world.
I. History of Evolution
1795- Hutton published a detailed theory about _________________ ____________ that
shaped the Earth.( pg 289)
1798- Malthus predicts the human population will grow _____________ than the space and
food supply can sustain it.
1809- Lamarck publishes his theory of the inheritance of _________________ traits.
______ or __________. (pg 287)
1833- Lyell explained processes occurring now have shaped Earth’s ___________________
features over __________ periods of time. (pg. 289)
1831- Charles Darwin sets sail on the _______________ from England for a voyage around the
world. (pg 287)
1836- Returns to England with many __________________
1859- Darwin publishes On the Origin of Species. He proposed the mechanism for evolution
in which he called __________________________.
The word “evolution” is not used in The Origin of Species, however, Darwin refers to descent with
________________, which is descent with changes from other species over_________.
More on Darwin- very interested in nature and bugs. His father was a physician and thought that
Darwin should follow suit.
II. Evolution by Natural Selection (pgs 292-297)
1. Struggle for Existence- members of each species _______________ regularly for food, living
space, and other _________________ of life. Ex: predators are fast or have a particular way of
ensnaring prey; may be camouflaged or have protection (porcupine).
2. Survival of the Fittest
a. _____________________ - ability of an individual to survive and reproduce in its
specific environment.
b. _____________________ - inherited characteristic that increases an organism’s chance
of survival.
1. ________________
2. ____________________
3. _________________ color
4. ability to carry out photosynthesis
5. hunting methods- in groups or as individuals
3. Descent with ____________________________ a. Over long periods of time, ______________________ selection produces organisms that
have _________ structures, establish different niches or occupy different habitats causing
species of today to look different from their __________________________ .
b. This implies that all living organisms are related to one another or have common
ancestors- ___________ descent.
Thumb Lab
III. Evidence of Evolution (pgs 288-289; 350)
1. Fossil Record
Paleontologist- scientists who study _________________
What is a fossil? ___________ remains or evidence of an ______________ organism
Relative Dating: the age of a fossil is determined by comparing it’s ___________ with that of
fossils in other ___________ of rock.
Radioactive Dating: is the use of _________-________to determine the age of the sample
Half-Life: length of _________ required for half of the radioactive atoms in a sample
to___________.
*Examine the fossils provided. View the diagram below and complete the following questions.
1. How many layers of rock are being observed? 1 2 3 4
2. What kind of rock are the layers above most likely to be? _______________________
3. Which fossil is probably older? A or C
4. Which fossil is probably the most recent? A B C D
5. Which fossil is probably the most complex? A B C D
6. Which fossil is probably the most simple? A B C D
7. How did you know which fossils are more simple or
more complex?_______________________________
2. Homologous Body Structures (pg 302)
Defined as: _____________ that have different mature __________ in different organisms but
develop from the same_____________ material.
*Same in structure but different in use.
A. Carefully examine the drawings of the various bones shown above. Look for the similarities
among the various animals.
B. Color each part of the human arm with a different color. Then color the corresponding bone
in each of the other animals the same color as the human bone.
C. Describe the function of each limb above:
a. Human _____________________
b. Whale ______________________
c. Cat ________________________
d. Bat ________________________
e. Bird _______________________
f. Crocodile ___________________
3. Analogous body Structures (pg 303) – body structures that look and preform similar functions
amongst different species but organisms are ____similar in _______.
4. Vestigial Organs or Structures (pg 304)
Defined as: organs or structures that are so _____________ in size that they are “vestiges” or
traces of homologous organs in other species. No longer have a known _______________.
A. The cave fish and minnow shown below are related, but the cave fish is blind. Explain why
eyesight is not an important adaptation to life in a cave. _____________________________.
B. Does the appearance of the cave fish and minnow suggest common ancestry? Yes or No
Why?
___________________________________________________________________________
C. Do vestigial organs serve a useful purpose or function? Yes or No
D. Name one human vestigial organ: _______________________.
E. Organs or structures that have lost their function in organisms and become reduced in size
are called:_______________________
5. Similarities in Embryology (pg. 299-301)
Defined - Same groups of ______________ cells develop in the same _________ and in similar
___________ to produce the tissues and organs of _______ vertebrates.
A. Study the embryo diagrams in the Power Point and look at the similarities between the early
development of the different animals.
B. Which of the different animals is most similar to the human? Fish or Rabbit
C. How does a comparison of embryos provide evidence of evolution?
___________________________________________________________________________
D. Similarities in early development indicate what is at work? ___________________________
E. As the embryos grow and develop, what happens to the similarity of the embryos?
___________________________________________________________________________
6. Cellular Evolution (pg 363)
The endosymbiotic theory proposed that _______________ cells arose from living
communities formed by ________________ cells.
7. Molecular Biology
Differences in amino acid sequences and DNA sequences are ___________ between species that
are more ______________ related than between species that are more ______________ related.
*Lab - Comparing Amino Acid Sequences or “A Strange Fossil”
Summary of Darwin’s Theory (pg 294-295)
 Individual organisms in nature differ from one another
 Organisms produce more offspring than can survive, and many do not reproduce.
 Members of each species must ______________ for limited _______________.
 Each organism has different advantages and disadvantages for the struggle of existence.
 Individuals best _________ to their environment _____________ and reproduce. If not suited
organism will die or go extinct all together.
 Survival of the _____________.
 Species _________ over time.
 Species alive today have descended with__________________.
 All organisms on Earth are united into a _________ tree of ________.
IV. Genes and Variation (pg 316-317)
1. Gene pool: Is the _____________ genetic information of _____ the members of a ___________
population.
2. Allele frequency: Is the number of times _________ __________occurs in a gene pool compared
with the number of times _________ alleles occur.
3. Sources of Gene variety or _______ ___________________come from chance mutations and gene
shuffling during sexual reproduction.
4. Genetic Equilibrium: Allele frequencies remain_____________ .
5. Hardy-Weinberg Principle: Allele frequencies in a population will remain constant ________ one
or more factors ________ those frequencies to ___________ . (pg 328)
Five conditions needed to maintain genetic equilibrium: (impossible in nature)
a. There must be ___________ mating.
b. The population must be very _________.
c. ____________ into/out of the population.
d. _______________.
e. ______________ selection.
Optional Feeding Frenzy Lab – Natural Selection Simulation
V. Evolution as Genetic Change (Pg 323-325)
1. ________________ Flow- movement of genes into/out of a population - introduces new alleles and/or
changes allele frequencies: Example: _______________________, migration, transfer of
_________________ population, movement of _____________________: pollen, sperm and ______
of ocean organisms.
2. Genetic ______________ - change that occurs due to _____________- ________________________
(wipe out entire gene pools), _______________________ (caribou, monarch butterfly), “_________”
(Elephant seals); has a greater effect on small populations.
3. ___________________________________- monogamy, mate selection
4. ____________________- produces totally new alleles (sickle cell occurs randomly in 5/100,000,000).
May or may not affect an organism’s ability to adapt.
5. ______________ ____________ - The loss of genetic variation when a new smaller colony is formed
from an original larger population. Over time this creates different frequencies from original species.
VI. Natural Selection - nature chooses which traits are best suited by selecting against
certain characteristics; it is the most disruptive factor to genetic equilibrium. (pg 318-321)
Nature chooses in 3 different ways...
1) ___________________________________- Average trait has the advantage
Example: Brown rabbits living in prairie grasses are better adapted than black or white
rabbits. Therefore the black and white alleles are selected against and will be taken out
of the gene pool.
2) __________________________________- Extremes have the advantage
Example: A fire burns the prairie grasses. The black rabbit is now better adapted.
Therefore the brown and white rabbits are selected against and are taken out of the gene
pool.
3) __________________________________- Average trait has a disadvantage
Example: Dark, tan and light colored limpets (shelled marine organism) live on rocks.
Sea gulls can’t see dark limpets on dark rocks or light limpets on light rocks. They can
see the tan limpets on either rock color and will eat them.
Let’s try some problem solving. Below are three graphs showing the 3 ways nature chooses traits.
See if you can correctly label each graph using the terms listed above.
______________________
______________________
_______________________
*Any change in equilibrium causes changes in a population over a long period of time.
Internet demo: Peppered Moth & Lab: Peppered Moth Survey
The Process of Speciation (pg 332-334)
VII. Speciation- (formation of new __________________)- results from _____________________
isolation- when members of two populations cannot interbreed and produce fertile offspring.
Kinds of Isolating Mechanisms:
1. ________________________ Isolation- two populations are capable of interbreeding but have
differences in _________________ rituals.
2. ________________________ Isolation- two populations are separated by geographic
_____________________ like rivers and mountains .
3. ________________________ Isolation- two or more species reproduce at different
_______________________; ex. Orchids in a rainforest; frogs
Patterns of Evolution
VIII. Macroevolution:
(pg 338) 1. _______________ extinctions- more than 99% of all species that ever lived are now
____________________; wipes out whole ecological systems; ex- dinosaurs.
(pg 340) 2. Adaptive ___________________ - fossils or living organisms show a single species or a
small group of species have evolved into ______________________ forms that live in
different ways. Ex. Darwin’s finches
(pg 336) 3. __________________________ evolution- _____________________ organisms come to
resemble one another. Ex. Sharks, penguins and dolphins.
(pg 336) 4. __________________ _________________ come from common ancestor but adapt to
different environments. Ex. The finches’ beaks on the different Galapagos islands.
(pg. 337) 5. ___________________________- _______________ species evolve in response to change
In each other over time. Ex. Orchid and hawk moth.
(pg 339) 6. Punctuated ___________________ - describes a pattern of long, _______________ periods
interrupted by brief periods of more _____________ change.
VIIII. Phylogenetic Tree- show common ancestry and lines of descent (pg 510-513)
A phylogeny, or evolutionary tree, represents the evolutionary __________________ among a set of
organisms or groups of organisms, called taxa (singular: taxon) that are believed to have a ___________
________________.
-The tips of the phylogenetic tree represent groups of
descendent taxa (ex. Sharks & amphibians) 
-The internal nodes of the tree represent the
________ ________________ of those descendents.
-The tips are the present and the internal nodes are the
_____.
-Two descendents that split from the same node are called
____________ _____________. (crocs & birds) 
*they have a lot of evolutionary history in common and very
little evolutionary history that is unique to either one of the two
sister species.
*that they have a ___________ ___________ that is unique to them.