Download Darwin



He noticed that they had very different
climates
He was interested by the different land
tortoises
◦ Their shells differed from island to island


He noted that the birds had different shaped
beaks
He collected all of this data not knowing its
significance, he later analyzed the data and
began to come up with a theory.



He debated whether or not to publish his work.
He received a letter from Alfred Russell Wallace
who found the same things, so he decided to
publish is work.
On the Origin of Species was the name of his
book
◦ Proposed a method of evolution called natural selection

Coined the term artificial selection
◦ Artificial selection: nature provided the variation, and
humans selected those variations they found useful.

Struggle for existence: members of each
species compete regularly to obtain food,
living space, and other necessities.
◦ Predators that are faster or have a particular way of
ensnaring other organisms, will catch more prey.
◦ Those prey that are faster, better camouflaged, or
better protected can avoid being caught.

The ability of an individual to survive and
reproduce in its specific environment.
◦ Result of adaptations.
◦ Adaptation: any inherited characteristic that
increases an organisms chance of survival.
 Behavioral, physiological, or anatomical.


Individuals with characteristics not well suited
to the environment will either die or leave few
offspring
Individuals that are well suited to their
environment will survive and reproduce most
successfully



Over long periods, natural selection produces
organisms that have different structures,
establish different niches, or occupy different
habitats
As a result, species today look different than
their ancestors
Implies that all living organisms are related to
one another


All species (living and extinct) were derived
from common ancestors
A single “tree of life” links all living things