Download 1. Who is Charles Darwin and why is he included in Chapter 14

1. Who is Charles Darwin and why is he included in Chapter 14?
Charles Darwin was a neutralist, the student of nature and he is the one who has presented the
Theory of Evolution after taking a trip around the world. He has presented his conclusions on
geology, fossils, biogeography, on natural selection, and adaption. Chapter 14 was titled as
Evolution and it’s the Darwin who has worked a lot for this section and have a great
contribution.
2. Explain Lamarck’s theory of the “inheritance of acquired traits”. Why is this theory
not true? (Please include your own example to “prove” that inheritance of acquired traits
does not work)
According to this theory the use and disuse of structures can produce some heritable changes.
Moreover, changes acquired can be inherited to offspring’s but this theory does not make any
sense. For example if someone is a body builder and develops his muscles after heavy exercise
then his children will not inherit large muscles as inheritance has a relationship with genes.
3. Define adaptation. What is the relationship between natural selection and adaptation?
The adaptation is a sort of characteristic that makes an organism more suitable for its
environment. Mostly it takes numerous generations for an adaptation to develop. According to
Darwin the consequences of natural selection is actually a population that was better adapted to
its local environment than that of previous generations.
4. List the 4 steps of Natural Selection.
The four steps of natural selection are given below:
 The members of the populations contain heritable variations.
 Individuals having favorable traits can survive and then reproduce to a greater extent than
those who lack such traits.
 Population produces more offspring than the resources of an environment can support.
 Throughout the generations, a greater proportion of the population possess some
favorable traits and population become adapted to the environment.
5. What anatomical evidence did Darwin use to support the idea of a common decent
hypothesis?
According to Darwin common descent hypothesis has offered a reasonable explanation for the
vestigial structures and anatomical similarities among the organisms. Vestigial structures are
fully developed anatomical features in one group of organisms and are nonfunctional in other.
6. Define natural selection (Ch. 15) and list the types of selection.
In natural selection, adaptation occurs when more fit individuals reproduce more than others.
Such individuals have traits better suited for survivals in the environment and over generations
the frequency increases. The types of selection are given below:
Directional selection: Dark-colored peppered moths become prevalent in polluted areas then
curve sifts in one direction.
Stabilizing selection: When most babies have intermediate birth weight then curve peak
enhances.
Disruptive selection: When British land snails vary because of geographic range then two peaks
of curve become.
7. What connection do mutations have to evolution?
Mutations are permanent genetic changes and they are considered as raw material for the
evolutionary change. Both of them have a connection as no new variations among the members
of the population can occur without mutation.
8. Define species as discussed in Chapter 16. What are the limitations of this definition?
Species is a group of organisms that can be inherited. The members of species can be
reproductively isolated from members of other species. This definition has its limitations as
biological species concept cannot be applied to the asexually reproducing organisms. Moreover,
reproductive isolation may not be completed, that’s why some breeding between species can
occur.
9. What is adaptive radiation? (Include examples from the text)
During the adaptive radiation various new species evolve from a single ancestral species. For
example the species of finches living on the Galapagos Islands are descendants of a single type
ancestral finch from the mainland. Moreover the Hawaiian Islands has a wide variety of
honeycreepers and all descended from common goldfinch like ancestor.
10. Explain Linnean classification.
Linnean classification is a way of organizing living things. It has been given hierarchical levels
and this classification is from most to least inclusive:
Species, genus, family, order, class, phylum, kingdom, domain.