Carolus Linnaeus
Taxonomy: the ordering of the natural world
Question: How did relationships come to
exist?
Catastrophism
(the only explanation for change)
• The world began perfect
• Change explained through major disasters
(Catastrophies) on a scale not seen today.
• Examples: Noah’s flood
Thomas Malthus
Economist, concerned with
Overpopulation in Europe’s cities
Law of Biotic Potential
Orginisms will maximize their
production of offspring. More will
be born than can survive
What determines which will survive???
Inheritance of
acquired
characteristics
Darwin’s
Finches
• Adaptation
• Environment
plays a role
in shaping a
species
Natural Selection
(Darwin and Wallace)
Requirements:
1. variation within a species
2. more offspring produced than needed
to assure continuance of the species
3. environmental factors that favor one
variation over another
Mendelian Genetics
• Austrian priest
Gregor Mendel (18221884) carried out an
extensive series of
experiments in plant
breeding.
• His carefully
tabulated results
provided the basis of
what we know about
the mechanisms of
genetic inheritance.
Mendelian Genetics
Figure 2.8:
The seven
phenotypic
characteristics
investigated by
Gregor Mendel
in his
experiments on
breeding in pea
plants. Each of
the seven traits
has two distinct
phenotypes.