Transcript natural selection

EVOLUTION
BY NATURAL
SELECTION
3 WAYS LAMARK GOT
EVOLUTION WRONG
• Organisms DON’T have a
desire to change
• Use and Disuse DON’T
MATTER
• Traits must be GENETIC to be
passed to the next generation
3 MAJOR FACTORS
INFLUENCING DARWIN
• The age of the earth (Lyell)
• Population controls
(Malthus)
• Breeding programs--aka
Artificial Selection (Farmers)
ARTIFICIAL
SELECTION
Humans make sure that
only individuals with
more desirable traits
produce offspring
SURVIVAL OF THE
FITTEST
Individuals whose traits are
well suited to the
environment survive.
Those who aren’t die (or
leave fewer offspring)
NATURAL
SELECTION
The process in nature
where the most fit
organisms produce more
offspring
PEPPERED
MOTHS:
NATURAL SELECTION
IN ACTION!
LOOK AT THE MOTHS
BELOW AND PREDICT THE
TYPE OF HABITAT THEY
WOULD LIVE IN
PEPPER MOTHS
pre-industrialization
Which moth would be more fit?
WHY???
PEPPER MOTHS
post-industrialization
Which moth would be more fit?
WHY???
ON WHAT DOES
NATURAL SELECTION
OPERATE?
PHENOTYPIC
VARIATION
What is the cause of
Phenotypic Variation?
GENETIC
MUTATIONS
THE
DEVELOPMENT
OF NEW
SPECIES
POPULATION
a collection of
individuals of the same
species in an given area
that can breed with one
another
NICHE
the combination of an
organism’s habitat and
its job or role in that
habitat
NO TWO SPECIES
CAN OCCUPY THE
SAME NICHE FOR
VERY LONG!!!
WHAT HAPPENS IF 2
SPECIES OCCUPY THE
SAME NICHE FOR
LONG?
EXTINCTION
or
EVOLUTION
DIVERGENT
EVOLUTION
(aka Adaptive Radiation)
different species diverge
from a common ancestor
CONVERGENT
EVOLUTION
creation of organisms that
are similar in appearance and
behavior
(bats, birds, butterflies)