Evolution = Change over time
Microevolution = small changes over time within a species
Macroevolution (Speciation) = Over time, groups of organisms changed so
much that they can no longer reproduce with the original group.
I. Evolution terms
A.
Adaptation = trait
that allows an organism to survive and reproduce
B.
Variation =
individuals have different traits
C.
Mutation = change in
DNA. Most changes have no effect, some
are lethal, a few make an individual better adapted.
D.
Competition =
competing for limited resources
E.
Species = Mayr: group
of actually or potentially interbreeding organisms in a natural
population. Offspring are fertile.
F.
Fitness = ability of
an individual to survive and reproduce in its environment
A. Lamarck: Inheritance of acquired characteristics/ Use and Disuse
B.
Hutton: Geological
forces occur over long periods of time
C.
Malthus: population
increases FASTER than the resources à competition
III. Charles Darwin = Father of Evolution
1809,
HMS Beagle, Galapagos Island
1865,
published before Alfred Wallace
Four
Tenets (i.e ideas)
1. More organisms are made than the environment can support à Competition
2. There is a variation among offspring preadaptation.
3. Natural selection survival of the fittest. Environment
selects against traits
-Climate,
weather, competition predators, pollution.
-e.g.
Peppered Moth and Industrial Melanism
4.Individuals that home desirable traits
are more fit and leave more offspring
IV. Evidence for
Evolution
A. Fossil Record
Strata
in sedimentary rock
Newest,
Complex, Alive today
Oldest, Simple, Most
extinct
B. Homologous Structures: Same tissueà related
·
Analogous structures:
same functionànot
necessarily related
·
Vestigial organ-no
longer need it
ex.
Whale pelvic boneàland
ancestor
C. Embryology
vertebrates have similar embryos
Haeckel=”ontogeny recapitulates phylogeny”
D. Biochemistry
Conserved
sequences in DNA, Hemoglobin, Cytochrome C
”molecular
clock” molecule found in ETS
V. Hardy- Weinburg
Equilibrium
·
Demonstrates the
occurrence of natural selection by demonstrating a change in gene frequency.
·
Assumptions. Large
pop, random mating, no mutation, no migration, no natural selection
