Natural Selection

Download Report

Transcript Natural Selection

Microevolution
- Changes in
the genes of
populations
Macroevolution
 The appearance of
new species over
time
 “Speciation”
Patterns of Natural selection
If the Siberian Husky had heavier muscles, it would sink deeper into the snow, so they
would move slower or would sink and get stuck in the snow. Yet if the Siberian Husky had
lighter muscles, it would not be strong enough to pull sleds and equipment, so the dog
would have little value as a working dog
Peppered Moth: Biston betularia
 Industrial melanism study by Kettlewell
Genetic Drift
Convergent
evolution
Evolution of Camouflage
 Mantis:mimicry
http://www.pbs.org/
wgbh/evolution/librar
y/01/1/l_011_03.htm
l
Orchid and Bee: coevolution
http://www.pbs.org/wgbh/evolution/library/01/1/l_011_02.html
example
of
mimicry
in which
the
orchid
has
evolved
to
resemble
a female
bee
Crab spider: