Download 15.1 Darwin`s Theory of Natural Selection

15.1 DARWIN’S THEORY
OF NATURAL SELECTION
I. Developing the Theory of Natural
Selection
A. A. Darwin on the HMS Beagle
1. Darwin’s job was to collect biological and
geological specimens
B. The Galapagos Islands
1. Noticed that different islands had slightly
different varieties of animals
2. Suspected that populations from the
mainland changed after reaching the
Galapagos
D. Darwin continued his studies
1. Artificial selection – same as selective
breeding
E. Natural selection
1. Given enough time, natural selection
could modify a population enough to
produce a new species
2. The four principles of natural selection
a. Variation – individuals in a population differ
from one another
b. Heritability – variations are inherited from
parents
c. Overproduction – populations produce
more offspring than can survive
d. Reproductive Advantage – some variations
allow the organism that possesses them
have more offspring than the organism that
does not possess them
F. The Origin of Species
1. Evolution used only once and at the end of
the book
2. Natural selection not synonymous with
evolution, but it is a means of explaining how
evolution works.