Transcript Natural Selection - West Linn High School

Natural Selection
The Mechanism to Explain
How Evolution Works
Who was Charles Darwin?
(1809 – 1882)
• 1. British Naturalist – from a wealthy
family, well educated, trained in theology
• 2. H.M.S. Beagle: at age 22 he sailed the
world for 5 years as the ships naturalist
(instead of getting a real job like his family
would have preferred.)
• 3. Credited with the “Principles of Natural
Selection as the mechanism for evolution”
Who was Jean-Baptiste de
Lamarck? (1744 – 1829)
• French naturalist who
came up with the idea
of “Acquired
Characteristics” to
explain how evolution
works.
How do the Ideas of Lamarck and
Darwin compare?
• both were trained naturalists
• both believed in evolution: that
species change over time
Lamarck
• Organisms acquire traits they need to
survive and then pass those traits to their
offspring.
Darwin
• Organisms naturally vary or differ and the
strongest survive, passing on those traits
to their offspring.
Darwin’s Travels:
• At age 22 he set sail on the HMS Beagle for 5
years.
• Explored the South American coast.
• On his travels he saw an amazing diversity of life
and began to formulate his theory of natural
selection.
• His time in the Galapagos Islands are most
famed for showing diversity.
• Fossils he found in South America were also
very important to his theory.
Farmers
• Breed animals and
plants to get certain
traits in their livestock
and crops, called
artificial selection.
Robert Malthus (1766 – 1834)
• An economist.
• Wrote about industrialized society and it’s
plights. Many, many people were moving to
cities and there were many problems as a result.
• “There is an overproduction of offspring” (used
to be a good thing on the farm)
• “…not enough resources to go around” (not
growing their own food, cutting own firewood,
etc)
James Hutton (1726 – 1797) &
Sir Charles Lyell (1797 – 1875)
• Geologists.
• Examined rock layers in England and
across the Channel in France and then
figured out that the world was WAY older
than the church taught.
• Fossils of extinct species from deep buried
layers supported this.
• Faunal Succession
Alfred Wallace (1823 – 1913)
• Hard working field naturalist who came up with
the Principles of Natural Selection on his own
while doing fieldwork in Malaysia and Indonesia.
• Wrote to Darwin, someone he looked up to, and
told him his theory.
• Darwin sat on Wallace’s work while finishing up
his own theory and presented it as all his own.
• Wallace was too busy working out in the jungles
half way around the world to defend himself.