Unit 3
Evolution and the
Classification of
Life
Inquiry Assignment
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
The question is often asked: “Why are we
learning this? How is it relevant to my life?”
You have received a handout titled “Relevance of
Evolution”; this assignment has been divided into
four main areas, you will be responsible for only the
on specified on your assignment hand-out:
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Agriculture
Medicine
Conservation
Co-evolution of Species
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Due Date: Friday, May 8th
Ideas for an open Media Rubric:
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Essay
Poster
Pamphlet
Video
Webpage
Use the class-time provided (Monday-Wednesday) to navigate
the website, record key questions and record some notes that
will help answer each key question
Before beginning your project, carefully read through the
evaluation rubric and ask any questions before you begin
Unit Notes:

This unit will correspond to Unit 5 in your
Textbook (pp. 366-467)

Chapter 15 – Darwin's Theory of Evolution
Chapter 17 – The History of Life
Chapter 18 - Classification
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Darwin’s Theory of Evolution
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Evolution means simply “change over time”
Observed evidence confirms that modern day
organisms have descended from more ancient
ancestors
The scientific theory of evolution is an explanation
for why things change over time
This theory has greater support due to intense
investigation than either atomic or gravity theories.
The Travels of Charles Darwin
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During his travels along the H.M.S. Beagle,
Darwin made many observations and collected
evidence from both living species and fossils.
This led him to propose a hypothesis about the
mechanism behind how life changes over time
Darwin observed that the characteristics of many
animals and plants varied noticeably as he went
from island to island in the Galapagos

Q: Describe Darwin's Journey on the Beagle
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Figure 15-1 (p.369)
Darwin’s Observations:
Patterns of Diversity
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During 1 day in the Brazilian rainforest, Darwin identified 68
different beetle species; despite the fact he wasn’t even looking
for beetles
Darwin began to realize the magnitude of biodiversity on earth
Darwin found that animals are remarkably well suited to their
environment, sharing advantageous characteristics
Europe held surprisingly similar grassland ecosystems of
Argentina or Australia, however the organisms found in the
grasslands differed greatly, why no rabbits in Australia? Why
no Kangaroos in England?
Darwin’s Observations:
Living Organisms and Fossils
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Living organisms are only a piece of the puzzle;
Darwin also collected the ancient remains of long
dead organisms, called fossils
Some fossils resembled those of living species,
others looked like no other species ever observed
Questions that arose included:
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Why do species disappear?
How are they related to living species?
Darwin’s Observations:
The Galapagos Islands
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The most influential of all Darwin’s travels were the
Galapagos Islands
Although close together, each island had a unique
climate
Hood (smallest and lowest) was hot, dry and barren
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Very sparse vegetation
The Higher the altitude of the island, the greater the
rainfall and as a result, the greater the amount of
vegetation and animal-life
Certain animals, such as the Giant Tortoise, varied
predictably from island-to-island
Pinta
Tower
Marchena
Pinta Island
Intermediate shell
Fernandina
Isabela
James
Santa
Cruz
Santa Fe
Florean
a
Isabela Island
Dome-shaped shell
Hood Island
Hood
Saddle-backed shell
Darwin’s Theory - Summarized
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Individual organisms differ; some of this variation is heritable
(can be passed on to offspring)
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Organisms produce more offspring than can survive, and many
that do survive do not reproduce
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Look around the classroom, what traits vary from person to
person?
Some organisms never reach maturity due to starvation or
predation for example; many of those that do survive are often
sickly or not healthy enough to reproduce
Because more organisms are produced than can survive, they
compete for limited resources
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The organisms best able to find and use resources are more likely
to survive and reproduce.
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Each organisms has different advantages and disadvantages in
the struggle for existence. Individuals best suited to their
environment survive and reproduce most successfully. These
organisms pass on their heritable traits to their offspring. This
process of natural selection causes species to change over
time.
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The environment dictates who survives, and does not always
correspond to the fastest or strongest.
Species alive today are descended with modification from
ancestral species that lived in the distant past. This process by
which diverse species evolved from common ancestors, unites
all organisms on earth into a single ‘tree of life’
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All organisms share certain characteristics in common
Assignment
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Survival of the Sneakiest
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Read the hand-out and complete the questions at
its conclusion in your notebook on a new piece of
loose leaf. Hand in by the end of class.
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Like any theory, evolutionary theory continues to
change as new data comes to light
Evolutionary theory provides vital insights to
ecological and medical problems, giving us the
expertise to understand and prevent harmful
changes in our environment
Questions still remain:
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How do new species arise?
Why do species go extinct?
How did life begin?
Ideas that Shaped Darwin's Thinking
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During Darwin’s era, the scientific world was coming to terms
with both:
Geologist James Hutton’s 1795 assertion that the world was
more than thousands of years old, but rather millions was
critical to Darwin’s theory (small changes accumulating over
vast periods of time)
Charles Lyell’s assertion that scientists can only explain past
events in terms of processes that they can observe currently, as
the processes that shape our world today indeed shaped the
ancient world as well supported Darwin’s theory (mechanism
for change is the same now as in the past)
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Jean-Babtiste Lamarck was the first scientist to put
forward the idea that living things change over time;
his explanation stated:
By selective use and disuse of organs, organisms
acquired or lost certain characteristics in their
lifetime
These traits were passed on to offspring and over
time this process led to considerable change in the
overall species
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1.
Lamarckian evolution includes:
Tendency towards perfection
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2.
Use and Disuse
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3.
An innate (built-in) tendency exists within organisms
toward complexity and perfection
Can alter the size or shape of their body in new ways (i.e.
work out and become stronger; a bird that refuses to fly
would lose its wings over time)
Inheritance of Acquired Traits
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If during its lifetime, an organisms grew longer legs or
fluffier feathers, it would pass that trait on to its offspring
Lamarckian Evolutionary Theory
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Lamarck was incorrect in several ways,
namely that an organisms behavior has no
impact on its heritable characteristics
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Ex. if you lose your hands in an accident, your
child will be born with both hands
Lamarck was revolutionary for his time
however, as he put forward the idea that
organisms adapt to their environment, paving
the way for Darwin and other scientists
How are Lamarck and Darwin
Different?
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Lamarck suggested that organisms choose their
characteristics
Darwin suggested that natural variation exists
Lamarck suggested that organisms evolve to
become ‘perfect’
Darwin put forward that evolution occurs only in
response to a change in the environment; i.e. nature
selects which organisms are best suited to survive.
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Thomas Malthus is often associated with ‘doomsday’ whereby
the human species would collapse; people that believe
mankind is due for a collapse are often called Malthusian
Malthus believed that if the human population continued to
grow unchecked, sooner or later there would be insufficient
space and food for everyone
Darwin supposed that this tendency was more applicable to
plants and animals, as they produce more offspring than are
capable of survival (i.e. 1 oyster can produce 1 million eggs per
year; only a small fraction will survive)
Q: What factors determine which offspring are capable of
survival and reproduction?
Video Assignment
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1.
2.
3.
4.
5.
6.
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Watch each video segment, following a quick class
discussion, answer each question with as much detail as
possible.
Q: What is wrong with the statement: “Evolution is just a
theory”?
Q: Who Was Charles Darwin?
Q: How do we know evolution happens?
Q: How does evolution really work?
Q: How did humans evolve?
Q: Why does evolution matter now?
Optional Question:
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Q: Why is evolution controversial anyway?
Quick Assignment
Evolutionary Classification
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Construct a table that has five columns and six rows.
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In the columns, write the following heads: Animal Group, Example,
Legs, Fins, and Tail.
Place the following animal groups in their own row: Mammal, Bird,
Fish, Amphibian, Reptile, and Insect.
Give one example for each group, and then fill in the
information for that example. For Legs, write in the number of
legs that each animal has. Do animals with fins have legs? Do
animals with wings have legs? If so, how many?
Can you tell from your table if a fish is more closely related to a
bird or to an amphibian? Explain your answer.
Cosmos: with Carl Sagan - Evolution
Beaver
Muskrat
1. What does the
following picture
illustrate about the
distribution of similar
species?
2. Do you believe these
organisms are closely
related? Why?
3. Which animal has a
larger geographical
range, the coypu or
the muskrat?
Beaver and
Muskrat
Coypu
Capybara
Coypu and
Capybara
Figure 15-14
(p.383)
Homologous structures (fig. 15-15, p.384)
Turtle
Alligator
Bird
Mammal
Homologous structures are
one type of evidence for the
evolution of living things.
Ancient lobe-finned fish
Practical Applications of Darwin’s
Theory
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Prior to Darwin, variation among species was seen
as an unimportant, minor defect
In artificial selection, nature provides the variation
in a species, and humans select those variations
found useful
Artificial selection has given rise many domestic
plants and animals by selectively breeding for
different traits.
Meet the Super-cow
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Warning: some images of artificial insemination may be too graphic for
some students; please put your head down if you do not wish to watch
Optional Video: Samurai Faced Crab
Chapter 15 - Assignment
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15-1 (p.372)
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15-2 (p.377)
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Focus on the Big Idea
#5
15-3 (p.386)
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#2, 3
Notebook Check #3
1.
Chapter 5 Review
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2.
Justicia Now
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3.
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Types of human activities
Impact
6-2 Assignment
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5.
Humans in the Biosphere
2column chart
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4.
5-1 #3-5, 5-2 #1-5, 5-3 #1,2,4,5
1, 2, 3, 5
How Much Should it Cost?
The History of Life
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The fossil record provides evidence about the history
of life on earth, it reveals how different groups of
organisms have changed over time
There are two ways to date fossil evidence:
Relative Dating: Dating a fossil relative to the
proximity to different types of sedimentary rock and
other fossils
Radioactive Dating: Calculate the absolute age (in
years) of a fossil based on the remaining isotopes
contained within
Video
Comparing Relative and Absolute Dating
of Fossils
Can determine
Is performed by
Drawbacks
Relative Dating
Absolute Dating
Age of fossil with respect to
another rock or fossil (that is,
older or younger)
Age of a fossil in years
Comparing depth of a fossil’s
source rock stratum to the
position of a reference fossil or
rock
Determining the relative
amounts of a radioactive
isotope and nonradioactive
isotope in a specimen
Imprecision and limitations of
age data
Difficulty of radioassay
laboratory methods
How Do Fossils Form?
Water carries small rock
particles to lakes and seas.
Dead organisms are buried
by layers of sediment, which
forms new rock.
The preserved remains
may later be discovered
and studied.
Fossil Formation Activity
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Receive Answer Sheet; complete while we
navigate online
Web-link
Mystery Detective
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1.
2.
Earth is billions of years old. There were not any witnesses to
those early years. How, then, can scientists determine the
conditions on Earth long before there were any scientists?
Think about how you draw conclusions about occurrences that
you did not witness. If you saw the charred remains of a house,
for example, you could infer that it burned down.
List things that you can observe around you that lead you to
infer about events you did not see. (For example, what do skid
marks in the roadway tell you?)
Now, think about and list the evidence all around you that
scientists might analyze when trying to piece together a history
of Earth. How would finding the fossil of a sea animal in the
middle of a desert tell a scientist something about the past?
Evolution of Life – A Concept Map
Early Earth was hot; atmosphere contained poisonous gases.
Earth cooled and oceans condensed.
Simple organic molecules may have formed in the oceans..
Small sequences of RNA may have formed and replicated.
First prokaryotes may have formed when RNA or DNA was enclosed in microspheres.
Later prokaryotes were photosynthetic and produced oxygen.
An oxygenated atmosphere capped by the ozone layer protected Earth.
First eukaryotes may have been communities of prokaryotes.
Multicellular eukaryotes evolved.
Sexual reproduction increased genetic variability, hastening evolution.
The Miller- Urey Experiment
Mixture of gases
simulating
atmospheres of
early Earth
Q: Describe the MillerUrey Experiment in
your own words.
Spark simulating
lightning storms
Condensation
chamber
Water
vapor
Cold
water
cools
chamber,
causing
droplets
to form
Liquid containing
amino acids and
other organic
compounds
Origin of Complex Life –
Endosymbiotic Theory
Video
Chloroplast
Aerobic
bacteria
Ancient Prokaryotes
Nuclear
envelope
evolving
Plants and
plantlike
protists
Photosynthetic
bacteria
Mitochondrion
Primitive Photosynthetic
Eukaryote
Ancient Anaerobic
Prokaryote
Primitive Aerobic
Eukaryote
Animals, fungi, and
non-plantlike protists
Patterns of Evolution
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Macroevolution are the large scale
patterns and processes that occur over long
periods of time. The 6 major topics are:
1.
Extinction
Adaptive Radiation
Convergent Evolution
Co-evolution
Punctuated Equilibrium
Changes in developmental Genes
2.
3.
4.
5.
6.
Chapter 17 - Assignment
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17-1 (p.422)
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17-2 (p.428)
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#3, 5
#1-4
17-4 (p.440)
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#1-3, Thinking Visually
Analyzing Data
Changing Number of Marine Families
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Complete Activity on p.438 on separate piece
of paper
Due Date: Today, end of class
Exploration:
Modeling Adaptation (20 Marks)
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Complete the activity as described on p.387
Complete 3 Rounds of this activity with your partner,
recording your data each time (what was role, your
habitat, your score, the result)
Your write-up must include:
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Name, Date, Title, Partners
Sections: Problem, Materials, Procedure, Data,
Analysis/Conclusion (questions)
Complete the “Go Further” activity for 5 bonus
marks, capped at 100%
Evolution Unit Review
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Ch. 15 Assessment (p. 389)
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Complete #1-10, 27-30, 32, 34
Ch. 17 Assessment (p.443)
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Complete #1-7, 9-10, 27-31
Icons of Science - Evolution
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
During the course of this video, record some
brief notes from each section that seem
significant or are of interest
These notes will be part of a notebook check
at a later date.
Taxonomy
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Evolution is the process by which new
organisms come to be; natural selection is
the mechanism behind it.
To study the diversity of life, we must develop
a classification system to name organisms
and group them appropriately
This discipline is called taxonomy
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Web-activity Sample
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To avoid confusion caused by regional names, the
taxonomic system must be universal across borders
and languages.
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i.e. a Cow, Vache, Krava, Waka, Ushi are all names for the
same organism; the taxonomic name bos primegenius is
universal in all languages and countries
Q: What Canadian animal has more than one
common name?
A: Mountain Lion, Puma, Cougar, Panther all
represent the same animal, Felis concolor
Binomial Nomenclature
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Each species is assigned a two part name;
the name is written in italics, the first word is
capitalized, the second word is not.
The first name corresponds to the genus,
which represents a group of closely related
organisms
The second name corresponds to the
species
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Carolus Linnaeus was a swedish
botanist, who developed a system
that became the forerunner to the
modern taxonomic system
Each level of this system is called
a taxon
Linnaeus’s System of Classification
Kingdom
Phylum
Class
Order
Family
Genus
Species
Sea star
Grizzly bear
Black bear
Giant
panda
Red fox
Coral
Abert
snake
squirrel
KINGDOM Animalia
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The system is
organized from the
general to the
specific
PHYLUM Chordata
CLASS Mammalia
ORDER Carnivora
FAMILY Ursidae
GENUS Ursus
SPECIES Ursus arctos
Kingdom
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1.
2.
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The Largest and most inclusive taxon; separates
organisms on a very basic and elementary level
Linnaeus originally recognized only two kingdoms
Plantae
Animalia
In years to come, new kingdoms would be created
to classify microorganisms like Bacteria and
Protists
Phylum
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The 2nd largest group, separates organisms by a
more specific characteristic
Consists of a group of similar classes of organisms
i.e. Phylum Chordata consists of all organisms with a
spinal chord
These organisms share many aspects of their body
plan and internal functions in common
Class
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The 3rd largest group, even more specific
characteristics are used to differentiate these
organisms
Made up of similar orders of organisms
i.e. Class Mammalia contains all organisms
that are warm blooded, have body hair and
produce milk for their offspring
Order
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Broad category composed of similar families
i.e. the Order Carnivora contains many
organisms with similar characteristics
Q: What characteristics might they share?
Family
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A specific group of organisms that share a
great deal of characteristics with one another
Composed of similar Genus’s
i.e. The Family Ursidae is composed of all
existing bear species
Genus
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Small Group of very similar organisms
Composed of similar species
The Genus Ursus includes the grizzly and
polar bear; the panda is in a separate genus
called Ailuropoda
Species
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Often a Latinized description of a unique
characteristic or native location of the organism
i.e. Ursus Maritimus would refer to a bear that lives
near the sea or on floating ice pack, in this case a
polar bear.
Q: What type of organism is Panthera leo?
A: Lion
One Big Family
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How can you determine if one organism is closely
related to another? It may seem easy, but it isn’t, and
looks are often deceiving. For example, roses and
orchids are both flowering plants, but roses grow on
bushes or vines and have thorns. Many orchids don’t
even grow in soil—they can grow in trees! Rose and
orchid blossoms look very different, and roses and
orchids cannot produce hybrids, or offspring of
crosses between parents with different traits.
1.
Do you think roses and orchids are closely related?
Explain your answer.
2.
Now, apply the same logic to dogs. Different breeds
of dogs—such as a Labrador retriever and a
collie—can breed and produce offspring. So what is
the difference between the rose-orchid combination
and the Lab-collie combination?
3.
What defines a species? Is appearance important?
What other factors might be considered?
Assignment
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
Read Ch. 18-1
Complete questions:
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
#4-6
Video
Modern Evolutionary Classification
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Physical similarities are only a piece of the whole
classification puzzle
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How closely related are bats, bees and birds?
With the advent of Darwinian Evolution, biologists
now group organisms into categories that represent
lines of evolutionary descent (phylogeny)
Species within a genus share a recent common
ancestor, whereas species of different genus but still
in the same family share a more distant ancestor
Organisms that superficially appear similar may not
share a recent ancestor (i.e. convergent evolution)
Classifications using Cladograms
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
As unique characteristics evolve, new
species are formed; we call these
characteristics derived characters
Derived characters are used to construct a
cladogram, a diagram which illustrates the
relationships between organisms as it relates
to recently derived characters and more
ancient ones.
Crab
Barnacle
Limpet
Crab
Barnacle
Limpet
Molted
exoskeleton
Segmentation
Tiny free-swimming larva
CLASSIFICATION
BASED ON VISIBLE
SIMILARITIES
CLADOGRAM
Quick Lab:
How is a Cladogram Constructed? (p.453)

On a separate piece of paper, please
complete this activity and turn it in next day.
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Cladogram (3 marks)
Questions (6 marks)
Six Kingdom Classification System
1.
2.
3.
4.
5.
6.
Eubacteria – single celled prokaryotic organisms with a cell
wall composed of peptidoglycan
Archaebacteria – single celled prokaryotic organisms with a
unique cell wall; extremophiles (love extreme environments)
Protista – single celled organisms with varied characteristics
(if it doesn’t fit anywhere else…)
Fungi – heterotrophic organisms with cell walls made of
chitin; generally decomposers
Plantae – Photosynthetic multi-cellular organisms with cell
walls made of cellulose
Animalia – Heterotrophic organisms without a cell wall,
capable of locomotion
3 Domain System


1.
2.
3.
Scientists have recently proposed a more general
taxon than ‘Kingdom’ called a Domain
The 3 Domain System consist of:
Bacteria – corresponds to kingdom Eubacteria
Archaea – corresponds to kingdom Archaebacteria
Eukarya – Correpsonds to kingdoms protista, fungi,
animalia and plantae
The Tree of Life (aka a cladogram)
DOMAIN
ARCHAEA
DOMAIN
EUKARYA
Kingdoms
DOMAIN
BACTERIA
Eubacteria
Archaebacteria
Protista
Plantae
Fungi
Animalia
Living
Things
are characterized by
Eukaryotic
cells
and differing
Important
characteristics
which place them in
Cell wall
structures
such as
Domain
Eukarya
Prokaryotic cells
which is subdivided into
which place them in
Domain
Bacteria
Domain
Archaea
which coincides with
which coincides with
Kingdom
Eubacteria
Kingdom
Archaebacteria
Kingdom
Plantae
Kingdom
Fungi
Kingdom
Protista
Kingdom
Animalia
Real World Lab:
Classifying Organisms Using a Dichotomous Key (p.462)


Complete the Lab as described on p.462.
Must include: Title, Name, Partners Name (if necessary), Date,
Problem, Materials, Data, Analysis (questions), and Conclusion
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–
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
Part A must be completed independently
Part B may be completed independently or with a single partner;
you must include their name at the beginning of you lab report
4 questions & a conclusion are necessary in the writeup
Completing the “Go Further” portion of the activity is worth 5
bonus marks, capped at 100% (if you have
Closed-book midterm #2
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



Closed book
Covers all notes and activities from last
midterm to this point
Corresponds to Chapters 15, 17 and 18 in
our text
Based on previous open-book Unit Exams;
same format
Date: Tuesday, June 2nd
Exam Review

Ch. 18 Assessment (p.465)
–
Complete #1-10, 26-30