Department of Education
National Capital Region
Schools Division of Paranaque City
Self-Learning Modules
Science 10 Quarter 3 Week 5
Sources of Evidence for Evolution
Learning Competency:
Explain the role of hormones involved in the female and male reproductive
systems. (S10LT-lllb-34)
Objectives:
At the end of this module, the learners should be able to:
1. Explain how fossil records provide evidence for evolution using
images/pictures.
2. Explain how rock formation, geologic time scale, and carbon-14 dating can be
used in determining the age of fossils.
3. Explain how comparative anatomy provides evidence for
evolution using pictures/video clips
4. Explain how genetic information provides evidence for evolution
Let’s Understand (Study the Concept)
Organisms inhabiting the earth have changed over time, their structures, traits,
and abilities allowed them to adapt and survive in their environment. Data from the fossil
records, anatomy and morphology, embryonic development and biochemistry could be
analyzed to demonstrate if the evolution of life on earth has taken place.
Evidence from Fossil Records
Fossil teeth
Cast
Sources: (a) www.albertawow.com (b) www.earthhistory.uk
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Fossils are examples of evidence that paleontologists use in studying evolution. They
are traces of organisms that lived in the past and were preserved by natural processes or
catastrophic events. They can be remains of organisms which include bones, shells, teeth,
and feces embedded in rocks, peat, resin, and ice. A paleontologist is a person who studies
fossils.
Determining the Age of Fossils
Relative dating is used to determine a fossil's approximate age by comparing it to
similar rocks and fossils of known ages. Absolute dating is used to determine a precise age of
a fossil by using radiometric dating to measure the decay of isotopes, either within the fossil
or more often the rocks associated with it.
Hint of Evolution from Comparative Anatomy
Another hint of evolutionary concept is from comparative anatomy and structures from
different species which have similar internal framework, position, and embryonic development
are considered to be homologous. Homologous structures may perform different functions in
the species living in the different environment, or it may have the same origin but different
functions. Here are some examples of homologous structures: forelimbs of dog, bird, lizard,
and whale, which are structurally the same, but functionally different.
Sources: www.fossilera.com>articles>about fossils
Structures of unrelated species may evolve to look alike, because the structure is
adapted to similar functions. These are called analogous structures. Analogous structures
have similar functions but different origins.
Examples are wings of birds, bats, and insects that have the same function but different in
origin.
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.
Sources;www.fossilera.com>articles>about fossils’
Front limbs of man, cat, horse, bat, whales, and other mammals are made up of the
same kinds of bones, they just vary only in size and function differently.
The presence of homologous structures is a strong indicator that the organisms evolved from
common ancestors. This type of evolution is called divergent evolution.
Let’s Apply
Directions: Use the information below to answer the age of the fossils. And answer the guide
questions on your answer sheets.
1.
What is the oldest fossil?
____________________________________________
2.
Why is it important to know the age of the fossil?
________________________________________________
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Sources: Payawal P. (1993)
Let’s Analyze
Directions: Study tables 6 and 7 below. In a graphing paper, plot the information on Table 6
and Table 7 in a bar graph, and use different colors to represent each pairing of species.
What organism appears to be least related to humans
Table 6
Table 7
Source: Activity taken from Brittain T. (Biology the Living World) Lab. Manual 1989
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1. In Tables 6 and 7, which pair of organisms appear to be more related to
each other?
2. Which pair of organisms is the least related to each other? Why did you
say so?
3. If the amino acid sequence of the two organisms is similar, would their DNA be also
similar? Why?
4. Do you think the chimpanzee, gorilla, and humans have a common
ancestry? Explain your answer.
Let’s Try: (Evaluation)
Directions: Multiple Choice. Choose the best answer and write it on a separate sheet of
paper.
1. Where can most of the fossils be found?
a. Sedimentary rock
b. Granite rock
c. Lava flows
d. Black soil
2. Which of the following statements DOES NOT describe evolution?
a. Evolution is continuous.
b. Evolution refers to change.
c. The world is stable and unchanging.
d. If there is mutation, there is evolution.
3. Which pairs of animals show a correct example of homologous structures?
a. Wings of butterfly and bat.
b. Flipper of whale and forelimb of cat.
c. Fingers of human and arm of starfish
d. Tongue of frog and proboscis of mosquito.
4. In what era can the oldest fossils be found?
a. Cenozoic
b. Mesozoic
c. Paleozoic
d. Pre-Cambrian
5. Which of the following statements best explains the Theory of Natural
Selection?
a. Organs that are not used may disappear while organs that are constantly
used may develop.
b. In nature, the organisms with desirable characteristics may survive while
those with weaker traits may not.
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c. Organisms develop desirable structures to survive in a given environment.
d. Acquired characteristics of parents can be passed on to offspring.
Let’s Create
Directions:
Ask your family members to help you execute this simple yet worthy enjoyable home
activity. Follow the laboratory activity below. Keep in mind every instruction and try to be
observant of the possible result. Enjoy while learning a lot!
FOSSIL AS EVIDENCE OF EVOLUTION
MATERIALS:
Any bowl-like container,
1 Kg white cement, water, basin, oil, leaf, shell, stirring rod, pin
(Note: if white cement is not available, they can use clay or gelatin as
substitute.)
PROCEDURE:
1. Mix the white cement and water in a basin.
2. Stir it with a stirring rod until it becomes pasty.
3. Apply oil to the surfaces of the leaf, shell, and bowl-like container.
4. Place the shell and the leaf at the bottom of the bowl-like container 5.
Pour the mixture into the bowl-like container covering the leaf and the
shell.
6. Set aside undisturbed until the cement becomes
hardened.
7. Remove the cement in the bowl-like container 8.
Carefully remove the shell and the leaf with a pin.
Criteria
Details and
Information
Method of
Presentation
Techniques/
Creativity
Accuracy
Excellent
(4)
All parts of the
presentation were
clear and
interesting
Proficient
(3)
All the parts of the
presentation said
something rather
important
Adequate
(2)
Most of the parts of
the presentation
said something
vaguely important
Limited
(1)
Much parts of
the
presentation
needed
improvement
Understandable,
unique, and
exemplary
Unique but not
organized
Not unique but
organized
Not unique
but not
organized
Create a powerful
image
Create an
interesting image
Create an adequate
image
that
is
moderately suitable
Create an
adequate
image which
is not suitable
Information
contains essentially
no errors
Information
contains minor
errors
Information contains
errors
Information
contains
many
errors
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