2. Do you know why dinosaurs no
longer exist today?
3.
4.
5.
6. MELCs: Explain how fossil records,
comparative anatomy, and genetic
information provide evidence for
evolution (S10LT-IIIf-39)
Learning Objectives:
1. understand how evolution is being studied
from the fossil record and
molecular data;
2. Explain the different evidence of evolution.
3. Give the importance of understanding the
origin of life;
9. What is Biodiversity?
• Biodiversity is a term used to describe
the enormous variety of life on Earth. It
can be used more specifically to refer to
all of the species in one region or
ecosystem.
• Biodiversity refers to every living thing,
including plants, bacteria, animals, and
humans
10. Types of Biodiversity
• Species Diversity
• Genetic Diversity
• Ecosystem/Ecological
Diversity
12. What is Evolution?
• In biology, evolution is the change in
the characteristics of a species
over several generations and relies
on the process of natural selection.
13. What is Natural Selection?
• Charles Darwin’s theory of
evolution states that evolution
happens by natural selection.
• Natural selection is the process
through which population of living
organisms adapt and change.
• Individuals in a species show
variation in physical
characteristics. This variation is
because of differences in their
genes
14. Evidence of Evolution
Fossils are the preserved physical remains of
organisms that live in the pass and preserved by
natural process or catastrophic events.
Evidence from Fossil Records
16. Two types of Fossils
1. Body Fossils/Compression- it is usually the
hard parts of the body like bones, teeth and
shells which are fossilized, although traces
of skin feathers, and other soft tissues
have been found.
2. Trace Fossils/Imprints- are the preserved
marks of activity left behind by an
organism when it was still alive. This can
be foot prints, feces, or even the imprint of
ancient plant.
17. S
I T
P A L EON T L
O OG
Is person who studies fossils.
18. How ages of Fossils determined?
Relative Dating
- Is a method used to determine the age of the
rocks by comparing them with the rocks in the
other layers.
Absolute Dating Technique
-this is done by using the rate of decay of certain
radioactive isotopes.
Carbon -14 dating-Carbon -14 breaks down or
decays to form nitrogen-14; the rate of this decay
is constant e.g. half of the remaining Carbon -14
breaks down every 5,730 years.
19. Activity 1: Study the following pictures. Identify if
these are body fossils or trace fossils. Write your
answers on a separate piece of paper.
1. 3.
2. 4.
20. WHAT’S MY AGE?
Objective:
Determine the age of fossil.
Materials:
Figure 1 and 2 (sample fossils)
Procedure:
a.Determine the age of the following fossils when
the carbon-14 breaks down and becomes
nitrogen-14
Note: Use the information below to answer the
age of the fossils.
21. WHAT’S MY AGE?
• Guide Questions:
1.What is the oldest fossil?
2.Why is it important to know the age of the fossil?
5730
11,460
17,190
23. Evidence of Evolution
Homologous Structures
Evolutionary Patterns from Comparative Anatomy
-if two or more species share a unique
physical feature such a complex bone
structure or a body plan, they may all
have inherited this feature from a
common ancestor.
25. Evidence of Evolution
Homologous Structures
Evolutionary Patterns from Comparative Anatomy
homologous structure which are often reduce in size are known as
VESTIGIAL STRUCTURE.
26. Evidence of Evolution
Analogous Structures
Evolutionary Patterns from Comparative Anatomy
-looks similar and have similar functions, but are anatomically
different and belong to unrelated organisms.
27. Evidence of Evolution
Patterns in Embryonic Development
-species that are related exhibit similar embryonic development even in
adult stage the organisms are quite different.
28. Evidence of Evolution
Evidence from Amino Acid Sequence
-It was only in 20th century that DNA was discovered as a genetic material.
-DNA and amino acid sequences maybe explored to investigate
evolutionary concepts. These tools may provide identify and are used in
the classification of organisms to their respective genus and species.
At the basic level, all organisms that share:
• the same genetic material (DNA)
• The same or highly similar genetic code.
• The same process or gene
expression ( transcription and
translation)
• The same molecular building blocks,
such as amino acids.
29. ACTIVITY 2:
AHA! ANALOGOUS! HOMOLOGOUS!
Directions: OPEN YOUR CAMERA.
SHOW
if the structures are homologous
And if they are analogous.
Show your answer after the 5 second
countdown.
32. Evolution of organisms is
a series of changes,
mutation, development
and to adapt in order to
survive in ever changing
condition of the
environment for the
continuity of life
33. Remember the following science concepts:
• Evolution is species change over time. Fossil
records, development and molecular biology and
genetics may provide possible evidence for
evolution.
• Convergent evolution is an increase in
similarities among species derived from different
ancestors as a result of similar adaptation to
similar environment.
• Divergent evolution is an increase in the
difference among descendants of a single
ancestral species as time passes.
34. Remember the following science concepts:
• Analogous structures are structures in different
organisms that are similar in function but different in
origin.
• Homologous structures are parts of different
organisms that are similar in structure but serve
different functions.
• Evidence in structure and molecular studies suggest
that organisms are related with one another
• Fossils are important because they give us clues
about, what life was like a long time ago, if we didn’t
have fossils, we would never ever know that
dinosaurs existed.
35. Assessment: Write the letter of the correct
answer. Write your answer on a separate
sheet of paper.
1. Where can most of the fossils be
found?
a. black soil
b. granite rock
c. lava flows
d. sedimentary rock
36. 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.
37. 3. Which pair of animals shows an
example of homologous structures?
a. wings of a butterfly and wings of a
bat.
b. flipper of a whale and forelimb of a
cat.
c. Fingers of a human and arm of a
starfish
38. 4. It is the remains of once living things,
fossil remains include bones, shells,
teeth, and also feces.
a. era
b. evolution
c. fossils
d. gene
39. 5. A scientist who studies the history
of life on Earth through the fossil
record.
a. astrologist
b. meteorologist
c. paleontologist
d. physiologist
40. Assessment: Write the letter of the correct
answer. Write your answer on a separate
sheet of paper.
1. Where can most of the fossils be
found?
a. black soil
b. granite rock
c. lava flows
d. sedimentary rock
41. 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.
42. 3. Which pair of animals shows an
example of homologous structures?
a. wings of a butterfly and wings of a
bat.
b. flipper of a whale and forelimb of a
cat.
c. Fingers of a human and arm of a
starfish
43. 4. It is the remains of once living
things, fossil remains include bones,
shells,
teeth, and also feces.
a. era
b. evolution
c. fossils
d. gene
44. 5. A scientist who studies the history
of life on Earth through the fossil
record.
a. astrologist
b. meteorologist
c. paleontologist
d. physiologist
Editor's Notes
Such extinction of dinosaurs and other organisms might cause by environmental factors or human activities.
Why some animals before are very different from the animals we have now?
Why some animals may look the same but have distinct difference from each other?
Or others may not be related to each other but may have similar features and characteristics?
let us know more about this on today’s lesson.
Charles Darwin’s theory of evolution through Natural Selection is widely supported by Evidence from different scientific fields.
FOSSILS WERE BURIED IN LAYERS OF SEDIMENATARY ROCKS. Fossils are solid evidence that organisms found in the past are different from the ones found today. Providing us a narrative on how life was in the past and how organisms evolve over millions of years.
WHAT TYPE OF ROCKS MOST FOSSILS WERE FOUND?
For an organism to become a fossil, it undergoes the process calles
PALEONTOLOGIST ALSO DETERMINE THE AGE OF THE FOSSILS THROUGH THEIR POSITIONS IN THE SEDEMENTARY ROCKS.
The younger rock is found on the top layer and the older rock is found in the bottom layer. Relative dating method depends upon the assumption that the age of a fossil is based on the relative age of the rock from which they are found; the technique is also used to date the rock based on the fossil it contained. This makes the method unreliable and require Carbon – 14 dating, other radioisotopes dating, and molecular techniques.
FOSSILS HAVE NO LIVING REPRESENTATIVES TODAY DUE TO EXTINCTION.
Divergent evolution proposed that homologous structures that developed from common ancestors may have different functions .
Homologous structures if two or more species share a unique physical feature such a complex bone structure or a body plan, they may all have inherited this feature from a common ancestor.
For example of homologous features the four limbs of humans, horse, whale, turtle, frog or bird look pretty different on the outside.
For example of homologous features the four limbs of humans, horse, whale, turtle, frog or bird look pretty different on the outside.
However, if you look the bone structure of the four limbs you’ll find that the pattern of bones is very similar across species. Sometimes organisms have structure that are homologous to important structure in other organisms but have lost their major ancestral function. We call these structure that are oftern reduce in size are known as VESTIGIAL structure.
Sometimes organisms have structure that are homologous to important structure in other organisms but have lost their major ancestral function. We call these structure that are often reduce in size are known as VESTIGIAL structure. Example of VESTIGIAL STRUCTURE is the tailbone of humans, the hind leg bone of whales and the underdeveloped legs found in some snakes.
Not all physical features that are look alike are marks of common ancestry instead some physical similarities are analogous.
Example of the analogous structure are the Wings of insects, birds, bats which they use for flying. In analogous they evolve independently in different organisms they live in similar environment or experience similar selective pressure. This process is called convergent evolution.
For example, the embryo of fish, salamander, tortoise, chicken and human are similar during the first stage of their embryonic development. And have several homologous structures that are not present when the organisms are adults.
Therefore, genetic information as evolutionary evidence through finding similarities in DNA sequences is fairly modern. But by far provides the strongest evidence of the theory of Evolution. DNA and amino acid sequences maybe explored to investigate evolutionary concepts. These tools may provide identify and are used in the classification of organisms to their respective genus and species. At the basic level, all organisms that share:
the same genetic material (DNA). The same or highly similar genetic code. The same or highly similar genetic codeThe same process or gene expression ( transcription and translation)
The same molecular building blocks, such as amino acids.
The greater the similarity in amino acid sequence, the closer the relationship of the organisms. The organisms which are similar in structure and also possess similarity at the biochemical level could probably have a common ancestor.
Evolution of organisms is a series of changes, mutation, development and to adapt in order to survive in ever changing condition of the environment for the continuity of life. That is the reason why organisms try to cope up and with stand all the difficulty they might encounter just to stay alive. Just like the Covid-19 virus it is not known by the body yet but once organism is already immune and take measures to fight the virus, they will survive. SO IT IS VERY IMPORTANT FOR US TO GET VACCINATED AND TO FOLLOW ALL THE HEALTH PROTOCOLS FOR US TO SURVIVE THIS VIRUS. REMEMBER All organism develops and mutate… They EVOLVE because of the changing environment.
