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1. Pick up all handouts
2. If you did not turn it in last time:
Place your lab notebook in the
crate in front of my desk.
• Place a tab on the page with your bird
beak lab.
– Tabs are on the stool by the crate
Evolution Terms
Artificial Selection
Which plants would you allow to reproduce if
you wanted the most amount of food?
Artificial Selection
Which cow would you allow to reproduce if
you wanted the most meat per cow?
Natural Selection
Which rabbits are most likely to get eaten by
the coyotes during snowy winters and not
pass on their genes for fur color?
Natural Selection
Which bear is most likely to have success at
sneaking up on its prey in a snowy
environment?
Natural Selection
Which bear is most likely to drown (from not
keeping its head above water) if they lived
in an environment where they had to swim
from one block of ice to another?
Homologous Structures
Same structure/different function
Homologous Structures
Same structure/different function
Analogous Structures
Different structure/same function
Vestigial Structure
• Structure that does not serve original
function—it did not increase or decrease
chance of survival or reproduction
Vestigial Structures
Camouflage
Mimicry
Organism looks like a more dangerous
specie to survive
Adaptation
Any change that better enables an organism
to survive and/or reproduce
Longer beaks allow birds to get
nectar/pollen that is deep inside of a flower
Gene Pool
• All of the alleles in a population (shallow
gene pool means a lot of people with the
same genes , resulting in less diversity,
more diseases, less evolution/adapting if
the environment changed)
Genetic Drift
Any change in the frequency of alleles by
chance events
Genetic Drift
Speciation
• Formation of a new specie from an
existing specie
Speciation
Isolation
• Reproductive Isolation – mate at
different times or have different mating
rituals
• Geographic Isolation – physical barrier
divides a population and each evolves in
their new environments
Divergent Evolution
• Species that were once similar to an
ancestral specie
Convergent Evolution
• Distantly related organisms evolve similar
traits
Gradualism vs. Punctuated
Equilibrium
• Gradualism - speciation that is slow
(adaptations take a long time)
• Punctuated equilibrium – hypothesis that
evolution happens quickly with long
periods of equilibrium