- Charles Darwin sought to explain how evolution occurs, not whether it occurs, as it was generally accepted that organisms change over time. However, the mechanism of evolution was unclear. - Darwin hypothesized natural selection as the mechanism of evolution, where traits beneficial for survival in the environment are selected for and passed on, leading to changes in populations over generations. This provided a testable explanation. - The work and ideas of contemporaries like Jean-Baptiste Lamarck, Georges Cuvier, Charles Lyell, Thomas Malthus, and Alfred Russel Wallace influenced and shaped Darwin's development of the theory of natural selection.

1. FYI…
This is the problem with Intelligent
Design and its proponents. They
have no testable mechanism to
offer as evidence of its scientific
validity.
Introduction to Physical Anthropology
ANTHRO 101 – ONLINE
Historical Influences Blog Post
Due Wednesday of Week 1 (Comments due Thursday)
Week 1 – Historical Influences on Darwin: BACKGROUND
The life’s work of Charles Darwin’s did not seek to provide
evidence that evolution occurs. Even 160 years
ago, it was generally understood that organisms change over
time. Scientists, however, were reluctant to
pursue this avenue of inquiry due to the social repercussions of
the time, with the church frowning on any
ideas that seemed out of line with religious and biblical
doctrine. Look at what the church did to Galileo

2. when he dared to argue that the sun was the center of our
system of planets instead of Earth! Imagine the
pressure to avoid discussing the idea that organisms, including
(and especially) humans, might evolve and
change.
Evolution is a natural process, observable in the world
around us. What was in question during Darwin’s time,
and what he sought to explain, was how evolution
happens, not if. Darwin’s hypothesis (now a theory), that
populations of organisms change over time in response to
environmental stress, provided a mechanism that
explained how this process of evolution worked. More
importantly, the mechanism of natural selection provided
a testable, falsifiable explanation that possessed powerful
predictive value, meaning that it allowed scientists to
predict what they expected to see in the natural world if natural
selection really was the mechanism by
which evolution worked and then check to see if those
predictions were true.
How does evolution work?

3. Here are some key points to remember regarding the logical
argument
supporting Darwin’s theory of evolution by the mechanism of
natural
selection:
exponentially. Two rabbits are roughly capable of
producing approximately 200 rabbits in their lifetime. Imagine
if all 200 baby bunnies had 200
hundred more baby bunnies… and so on… and so on… That is
exponential growth that has the
potential of having us up to our eyeballs in rabbits. But we
aren’t up to our eyeballs in rabbits, are
we? Why not? This question is the starting point of Darwin’s
work.
potential? Something is keeping those
rabbits from producing all those bunnies. Baby rabbits are
costly to the parent to produce. The
parent needs time, shelter, food, water and protection from
predators. These needs are called

4. “resources”.
planet has a limit of much it can
hold and produce. There will not be
enough resources available for all organisms to reproduce as
many offspring as they can.
successful in their reproductive efforts.
The rabbits with more food and water and shelter will reproduce
more offspring than those rabbits
with fewer of these resources.
random? Or are some organism better
“fit” to the environment, enabling them to compete more
successfully for resources and avoid
predation better than others? Darwin hypothesized that
organisms with traits that were better
adapted to their environment would have greater reproductive
success because those traits allowed
them to be more competitive for the things they needed to
reproduce.

5. adaptive to that environment will be
different. Organisms with those new adaptive traits will have
greater reproductive success than
others and those new beneficial traits will spread, producing a
change in the population. This is the
process of natural selection, essentially the process of the
natural environment selecting the
organisms that will be most successful.
occur! Survival is not enough. If you
don’t pass on your traits, evolution will not occur.
heritable. This means they must be passed
on reliably from generation to generation through reproduction.
This was actually a problem for
Darwin as he did not know how traits were passed on. The
current thinking of that time argued for
Fluid or Blending Inheritance, which actually blends out traits.
We will meet someone next week
who helped solve this problem.

6. cannot change their heritable traits; they
can only pass them on. Evolution does not occur within a
generation. It occurs between
generations.
important difference. The selective
force in artificial selection is not the environment, but instead
humans choosing which organisms
successfully reproduce and which ones don’t.
Blog Post Instructions (50 points):
Science is never completed in a vacuum. All scientists are
working in their current scientific environment,
filled with the ideas and explanations of the day. Here is a brief
(and incomplete) list of contemporary
individuals whose work and contributions influenced and
shaped Darwin’s work.
Jean-Baptiste Lamark
Georges Cuvier
Charles Lyell

7. Thomas Malthus
Alfred Russel Wallace
Create a new blog post that accomplishes the following (Due
Wednesday by 11:59 pm)
1. Select one of the five individuals listed above who you would
argue had the most influence over
Darwin’s development of his theory of Natural selection. This
could be a positive or a negative
influence.
2. Briefly (but completely) describe the contribution this
individual made to the scientific community.
You must provide one link to an online source of information
besides your textbook. No Wikipedia
sources! ( 10 pts)
3. From the bullet point list above (under “How does evolution
work?”), identify the point (or points)
most directly affected by this individual’s work and thoroughly
explain how this point was
influenced by your selected individual. Again, this could be a
positive effect, meaning Darwin built
upon the knowledge this information provided, or a negative

8. effect, meaning that Darwin
demonstrated that this individual’s idea(s) were incorrect and
the mechanism of natural selection
was an alternative explanation. (10 pts)
4. Could Darwin have developed his theory of natural selection
without the influence and ideas of this
individual? Explain. (10 pts)
5. How did the attitude of the church affect Darwin and his
eventual publication of his book On the
Origin of Species? (10 pts)
Make at least two significant, constructive responses to blog
posts of your fellow students, provided
positive and/or constructive feedback. (Due Thursday by 11:59
pm – 5 pts each)
Grading Matrix for Blog Post & Responses
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(40 pts)
Responses
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prior to the due date or
two responses are
made by the due date
that fail to demonstrate
effort or thoughtful
feedback.
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10. Two responses are
made prior to due date
that demonstrate effort
and thoughtful
feedback.
(10 pts)