How does
evolution
explain
biological
diversity?
Science
Module
Submitted to: sir Arnel Martinez
Submitted by: Jhan Martin Digo
Hi there!!!! My name is panda and we will have lesson
do you have an idea about evolution and biological
diversity? This lesson will show you answers on how
evolution can explain biological diversity so let’s go
and enjoy the fun.
Objectives:
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Read the direction carefully
Explain the lesson
This lesson helps you to your questions
Pre-test
Define whether it’s true or false.
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2.
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5.
evolution is defined as true change in a species through time.
adaption, survival, and extinction are closely related concepts.
evolution was the theory of Isaac newton.
the earth is estimated to be about 4.5 billion years old.
polyploidy refers to the established natural relationship among
organisms based on evolutionary history or line age.
Lesson:
In the previous grade level, we defined biological diversity or biodiversityas the variation
and variability of living organisms and ecological complexes occur.
Biodiversity covers “the genetic species, and ecological diversity in a given place at a given
time.
What do we know about species diversity?
Species diversity refers to the number and variety of living organisms.
How many species are there? Although only an estimated two million species of plants,
animals and microorganisms have yet been discovered, named, and documented
worldwide, taxonomists believe that are between 5 to 100 million species of living things on
earth. Why do living things share common characters? Apparently, different species
appeared at different geological periods. As cells come from pre-existing cells, so do living
things come from pre-existing life forms. Old species that emerged first changed and
diverged into more advanced forms of life primitive species may have given rise to new
ones.
Why are there so many different species?
The earth is estimated to be about 4.5 billion years old. For more than a billion years, there
was not a single living thing on earth. So how did these species of living things emerge? And
why are there so many different species now? The answer is speciation, a process that
explains how a new species evolved from a previously existing one. Speciation involves
isolation, divergence and the consequent loss of the ability to interbreed with the old species.
One of the mechanism by which populations give rise to new species is by polyploidy.
Polyploidy involves the development of multiple homogenous sets of chromosomes. The
brassica species are what we commonly eat as vegetables.
How does evolution contribute to biological diversity?
Evolution is defined as change in species over time. It may be expressed through variation,
speciation or phylogeny. Evolution accounts for the variation that occurs in members of the
same species. It explains why no two individuals in the same population are exactly alike.
We may be fair complexioned or dark skinned, with straight or curly hair, tall or short.
These different traits and the many different combinations in which they appear may have
resulted from genetic recombination or mutation. Genetic recombination is achieved during
sexual reproduction when genes of two parents combine in the offspring. Mutation is a
drastic change in the genes are translated to changes in the expression of certain physical
characteristics.
Post-test
Identify the sentences and find there meaning.
1. all of the different types of organisms/ecosystems on earth, and the
ecological process they are a part of?
2. where living interacts with non-living?
3. variety of different populations?
4. variety of genetic material found in living things?
5. organisms adapt to changes in the environment for survival?
6. different populations of species living in the same area?
7. refers to the changes in characters of organisms in a population due to
genetic recombination or mutation.
Ecosystem Diversity
Community
Natural Selection
Genetic Diversity
Biological Diversity
variation
Community Diversity
Key to correction:
Pre-test
1.
2.
3.
4.
5.
true
true
false
true
false
Post-test
1.
2.
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4.
5.
6.
7.
biological diversity
ecosystem diversity
community diversity
genetic diversity
natural selection
community
variation