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Name
NOTES
Date
Period
XBIO: Evolution Notes
I.
History
A. Disproving Spontaneous Generation/Abiogenesis
1. Redi________ - meat in 2 jars, one covered other uncovered
2. Spallanzani___ - broth in 2 flasks, one sealed other unsealed
3. Pasteur____ - flask with curved neck
B. Conclusion: Biogenesis – life can only arise from life
II.
Early Theory of Evolution
A. Lamarck
1. Theory of Use and Disuse
2. If an organism uses an organ it will become stronger
3. If an organism does not use an organ it will disappear
4. These acquired characteristics can be passed onto offspring
DO YOU THINK HE WAS CORRECT????
B. Giraffe Example
C. ??? If I work out a lot and become huge – will my offspring be born
with big muscles ??? Why or why not?
D. ??? If I color my hair red – will my offspring be born with red hair ???
Why or why not?
E. Conclusion: Acquired characteristics are NOT coded in DNA,
therefore they CANNOT be passed onto offspring
F. Conclusion: Lamarck theory was INCORRECT
III. Darwin – Theory of Evolution by Natural Selection
A. Trip – HMS Beagle to the Galapagos Islands
B. Origin of Species by Means of Natural Selection
i. Living things overproduce
ii. There is (genetic) variation among offspring
iii. There is a struggle to survive
iv. Natural selection is always taking place
C.
Natural Selection – the process by which the most fit organisms
reproduce
D. Survival of the Fittest – Reproductive success
i. Individuals whose characteristics are well suited to their
environment survive AND REPRODUCE
ii. Individuals whose characteristics are not well suited to their
environment with die AND leave fewer or no offspring
iii. Therefore – those individuals “more fit” survive to produce
offspring with their “more fit” characteristics
iv. Example – peppered moths (see slide)
E. Adaptations – variations in populations that have an advantage over
others in the same population (refer back to peppered moths)
IV. Evidence for Evolution
A. Fossils
1. In sedimentary rock
2. Imprints in soft sediment that hardens
3. Petrification – replacement of bones by minerals
4. Amber – think Jurassic Park
B. Comparative Anatomy
1. HOMOLOGOUS Structures – structures are similar but
with different functions (share a common ancestor)
a. Example – arm of a person, wing of a bird
b.
2. ANALOGOUS Structures – structures are different but
have similar functions (evolved independently)
a. Example – wing of a bee, wing of a bird
3. VESTIGIAL ORGANS/Structures – structures that no
longer have a useful function
a. Examples – 3rd eyelid, appendix, tailbone (in humans),
wisdom teeth
b.
c.
C. Comparative Embryology
1. Comparing the embryos and their development among
different animals
2.
D. Comaprative Biochemistry
1. All species use similar proteins/chemicals in their bodies
2. Examples – ATP, insulin, DNA
OVERALL CONCLUSION: Evidence for evolution can be found by comparing
several kinds of data, including: the fossil record, anatomy, embryology, and
biochemistry.