Download Evolution 1

Darwin was born into the family of a
prominent physician on February 12,
1809, in Shrewsbury, England. His
mother was the daughter of Josiah
Wedgwood, founder of the famous
pottery firm. In 1825 Charles entered the
University of Edinburgh to become a
physician. Two years later he entered
Cambridge University to study for the
clergy.
Darwin was a shy,
meticulous, wealthy
landowner who had an
extraordinary commitment
to intellectual honesty.
He is probably best
known for his theory of
Natural Selection and
his published works,
The Origin of Species.
In 1831 Darwin joined the HMS Beagle as the
naturalist for a circumnavigation of the world; the
voyage lasted five years.
Read a segment of Darwin’s Diary
Darwin kept a detailed diary of his trip and collected a
great many plant and animal specimens. Through
observations of such animals as tortoises and finches
on the Galapagos Islands, Darwin saw first-hand the
effects of variation and adaptation.
Darwin spent 22 years gathering evidence and
pondering arguments. It was not until 1859 that
Darwin finally published his Origin of Species.
Ideas that shaped
Darwin’s Theory of
Natural Selection
In the 18th century, it was commonly accepted
that the Earth was only several thousand
years old.
1. In 1785, the geologist James Hutton
proposed that the Earth is shaped by geological
forces that took place over extremely long
periods of time. He estimates the Earth to be
millions of years old.
Another geologist helped shape Darwin’s ideas.
2. In 1833, Charles Lyell explained in
his book Principles of Geology that
processes occurring presently like
volcanoes and erosion have shaped
Earth’s geological features over a long
period of time.
This understanding of geology influenced Darwin in two ways:
1. Darwin asked, “ If the Earth could change over time, might life
change as well?”
2. Darwin realized for life to change over time, the Earth had to
be millions of years old.
3. In 1809, Jean-Baptiste Lamarck published his
theory that organisms change within one
generation. This was a faulty assumption, but it
provided a means of explaining how organisms
change over time.
Darwin realized
from Lamark’s
work that
animals are
adapted to their
environments.
4. Another influence on Darwin was the
economist Thomas Malthus. In 1798
Malthus published his essay on the
Principle of Population stating that
human birthrate is higher that its death
rate, but famine, disease and war
prevent a huge population increase.
Darwin read Malthus’s work and realized that this
reasoning applied even more strongly to plants and
animals than it did to humans. Why? Because humans
produce far fewer offspring than most other species.
What Darwin Never Knew
Homework:
Look at the Video on “What Darwin Never Knew” on the
link provided below which is also available on my
Website and complete the worksheet.
https://www.youtube.com/watch?v=AYBRbCLI4zU