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Biology CP
Introduction to Evolution: How Did We Get Here?
Part 1: Introdution
1. Who is Charles Darwin? Write down anything you know about him and discuss as a class.
2. You are going to receive an excerpt from Charles Darwin’s diary. Half the class will read the excerpt
titled “Buenos Aires, Argentina” and the other half will read “Galapagos Islands, Ecuador.” The teacher
will choose which excerpt your group will read. If words are unfamiliar to you, please look them up.
Write down notes in the space below based on what you have read. When the class is done reading
their excerpts, groups should report their findings to the class. Each group should share at least one
thing they learned with the class.
3. Read the following out loud as a class: For Darwin, these observations led to his curiosity about the
relationships between species and the origins of new species. He developed the idea that many species
could emerge from one original species. He thought that species could change—or adapt—over time,
and that all species were related to a common ancestor. These ideas were the foundation of Darwin’s
famous theory of evolution.
Eventually Darwin came to the idea that the key to evolution was variation, or different characteristics
within a species. He observed that within a species individuals had varying characteristics, such as eye
color in people. Individuals with traits useful in their environments, such as finches whose beaks can
crack a specific nut, have a better chance of surviving to reproduce and pass along those traits.
Conversely, individuals with harmful traits, like an inability to digest a nut that is the only food source,
would not survive, and would not pass those traits to future generations. Darwin called this process
“natural selection.” It is also sometimes known as “survival of the fittest,” but Darwin himself did not use
that term.
Darwin started writing about his new theory almost immediately after returning to England after
the Beagle voyage, but did not publish his famous work On the Origin of Species by Means of Natural
Selection until 1859. By the time of his death in1882, his theory of evolution was widely, but not
universally, accepted. In later works Darwin discussed how natural selection applied to the process of
human evolution. He was faced with skepticism and controversy when he suggested that humans shared
common ancestors with primates like apes or monkeys, but today it is a commonly accepted theory.
HOW DO YOU THINK NATURAL SELECTION HAS FACTORED INTO HUMAN EVOLUTION? Answer this
questions below.
Part 2: Learned Activity
The Human Spark
1. Think about your family trees. How far back can you trace your ancestors-1, 3, 5, maybe even 10
generations? According to Darwin’s theory that all life on earth evolved from a common ancestor, a
person’s family tree actually goes back thousands, maybe millions of generations!
2. Watch the following video titled “The Human Spark: Links in the Evolutionary Chain” on the
SmartBoard and answer the following questions. Review the answers to the questions as a class:
(http://www.pbslearningmedia.org/resource/hs11.global.ancient.earl.evochain/links-in-theevolutionary-chain/ )
a. What specific characteristics or abilities, like skull and brain size, or new tools and inventions,
did our ancestors possess?
b. Why do you think those characteristics and abilities changed over time? Why ddi some things
change while others remained the same? Why did different groups have different abilities and
characteristics?
3. In pairs or small groups, you will get a print out of “Who’s who in Human Evolution.” Each group/ pair
will pick one of the four subgroups present in the interactive: early hominins, Australopithecus,
parathropus, Homo. (All subgroups should be covered). Read the fossils that are in your subgroup and
write in the space below which characteristics they think are similar to humans today and which are
different. When all groups are finished groups will share their observations as a class of their groups.
Answer the following questions (a.) when all groups have shared their observations:
a. Which characteristics made if all the way from early hominins to Homo sapiens? Which were
lost? Which were picked up along the way? Why do you think this happened?
Monkey Business
4. You will be given a copy of a timeline of life on earth. This timeline represents when different species
branched off from their ancestors and became a new distinct species.
5. You will also get a copy of how Ida fits into the primate family tree. Note: As part of the evolution
process new species branched off to form new ones but the original species still existed in some form
for a period of time. All branches of the hominin family tree have died off except for Homo sapiens.
However, many of our earlier ancestors still populate the earth. This access to our early ancestors can
give scientists insight into the origins of human behavior.
6. You will watch the following video: Human Nature
(http://www.pbslearningmedia.org/resource/hs11.global.ancient.earl.humnat/human-nature/ )
After watching the video answer the following questions and go over as a class:
a. Why does Laurie Santos study monkeys? What does her research suggest?
b. What are some of the different apes mentioned in the video?
c. What is one major different between humans and apes, as described in the video?
7. Some scientists feel that the evolutionary gap between humans and apes is still too wide and they are
looking for what they call “the missing link” – an ancestor that clearly ties the two branches of the family
tree. “Ida,” shown on the two timelines papers you were given, was a recent fossil discovery that some
scientists believe to be a crucial link in the chain of human evolution. Others are not so sure. Answer the
questions below and when complete go over these questions as a class.
a. What traits would you expect this creature to have?
b. Would it be classified as an early hominin or a primate?
c. What would its body look like?
d. How would it act around others?
e. What characteristics would it need to possess in order to be a direct ancestor or Homo
sapiens?
Part III: Culminating Activity
1. Remember: According to Darwin’s theory, all species evolved from a common ancestor ,even further
back than the earliest primate 55 million years ago. Look at the timeline of life on earth handout. Note
that before primates, our family tree included early mammals, reptiles, and even fish and worms.
2. In pairs or small groups go to: The Zoo of You (http://www.pbs.org/wgbh/nova/evolution/zooyou.html ). You may use your phone for this or the Smart Board as a class. Click on the interactive and
make a note below of any “oops” characteristics. Write down if you found anything particularly
surprising or interesting. Share what you found as a class.
3. Answer the following based on the “oops” characteristics. Go over your answers as a class.
a. How does these characteristics fit into Darwin’s theory?
b. Why do these characteristics appear in modern humans?