Download evidences for evolution

Evolution:
KEY WORDS/
QUESTIONS
The First
Evolutionary
Experiements
Theories of
Evolution:
Evidence & Theory: Ch. 13
NOTES
Spontaneous Generation:
Players: Redi, Spallanzani, Pasteur
Experiments:
A. Jean Baptiste de Lamarck:
KEY: -No variation exists within the population.
Variation can be acquired from a simple desire (You
want the characteristic/trait...work hard enough and
you will get it.)
-Once your parent has the trait, all the children will
also be born with the same characteristic.
Ex. Father was a professional wrestler that
worked out to gain muscles...his children will be born
with huge biceps!
B. Charles Darwin/Alfred Wallace:
-Darwin voyage & goals
a. Collected several fossils, didn’t really
know what to make of them. (Never actually
studied finches!)
b. Spent YEARS trying to make sense of data and
collected a myriad of data within these
years.
i. studied barnacles
ii. studied artificial selection in
pigeons
c. Didn’t publish any data b/c his wife/cousin
was VERY religious and he belonged to the
WHIG party (influential politics...his
findings would have destroyed his family
financially and politically)
-Wallace: contemporary of Darwin. Found the same
trends and findings while working in India/Africa.
Wrote to Darwin to clarify findings. Darwin got
worried he would be beaten to the punch, but he
coordinated a publication with Wallace. Since Darwin
had more info than Wallace, he is given the credit.
KEY FINDING: - Variation exists within the population
already. Those individuals that are best able to get
resources and stick around long enough to have babies
are considered the “best fit” for the environment.
AKA survival of the fittest.
-This variation that the parents were born with
themselves, can be passed to their offspring...as long
as the variation is in the DNA and the DNA is passed
in the gametes.
Darwin found human’s already picking traits that they
wanted in pets (Artificial Selection) and so he
Evolution:
Evidence & Theory: Ch. 13
postulated that if human’s can choose, so can nature,
hence Natural Selection.
REQUIREMENTS for NATURAL SELECTION
1. There is variation among the individuals of a
population, and this variation exists as different
gene alleles.
2. This variation can be passed on to offspring.
3. Parents have LOTS of babies, but only some will
survive to reproduce.
4. There is a limited supply of resources in any given
environment, so this sets up a competition to get
these resources.
5. Those that have the traits/correct allele versions
will be able to get these resources in order to live
in the environment.
6. Overtime, the population changes such that the
traits of the more successful reproducers become more
prevalent in the population.
EVIDENCES FOR EVOLUTION
The Fossil Record
A. DISTRIBUTION OF FOSSILS: Most direct evidence
for macroevolution (evolution on a BIG scale)
Relative Age: Look at the fossils pulled
out of the ground. Law of Superposition means the
further down you are, the older you are.
Absolute Age: To find the age of the
fossil, use radioactive isotopes to date.
B. Succession of Forms: Caminacules Lab & phylogeny
... you look like your relatives, but
occasionally there are blanks in the fossil
record. Either the line died out (Extinction) or
“missing links” pop up. Ex. Ambulocetus (whale
with legs), archaeopteryx (bird w/ reptile bone
pattern), Lucy.
Evolution:
Evidence & Theory: Ch. 13
Evidence for
Evolution:
1. Fossil Record
2. Embryology: all organisms
in their early developmental
patterns looked similar.
Links to perhaps a common
ancestor that was shared.
3. Anatomical Record:
Homologous/Analogous &
Vestigial Structures
4. DNA Evidence: compare the
DNA sequences among several
organisms. The most closely
related organisms have the
fewest number of differences
in their DNA
sequences.
(Usually chose a
common protein
gene to look at.)
BEST EVIDENCE FOR
RELATIONSHIPS!
Patterns of
Evolution:
1. Coevolution: long term evolutionary adjustment of
organisms to each other (Ex. Flowers and their
pollinators)
2. Convergent Evolution: organisms that have no
common ancestry, but look similar BECAUSE OF THE
ENVIRONMENT IN WHICH THEY LIVE. (Ex. Sharks and
dolphins)
3. Divergent Evolution: organisms that have a common
ancestry, but look different BECAUSE OF THE
ENVIRONMENT IN WHICH THEY LIVE. (Opportunity for
speciation.)
Pace of
Evolution:
*Only point of contention among the
evolutionists...how fast does evolution occur?
1. Punctuated Equilibrium
Evolution:
2.
Evidence & Theory: Ch. 13
Gradualism: