Download Evidence of Evolution

Theory of Evolution
Today
Supporting Evidence
1
Fossil Record
Earth is billions
of years old
 Fossils in
different layers
of rock showed
evidence of
gradual change
over time

2
Geographic Distribution of
Living Species
Different animals
on different
continents but
similar adaptations
to shared
environments
3
Homologous Structures: features that are
similar in structure but appear in different
organisms and have different functions 4
Homologous Body Structures
 Scientists
noticed animals with
backbones (vertebrates) had
similar bone structure
 May differ in form or function
 Example: limb bones develop in
similar patterns
»Arms, Wings, Legs, Flippers
 Develop through divergent
evolution
5
Analogous Structures: structures that perform
a similar function (in this example, flight) but
are not similar in origin; develop through
6
convergent evolution
Vestigial Structures:
remnants of organs
or structures that
once had a function
in an early ancestor
7
Evidence for Evolution - Comparative Embryology
Similarities In Embryonic Development
8
Chicken
Turtle
Rat
9
Human Fetus – 5 weeks
10
Similarities in DNA Sequence
11
Evolution
of
pesticide
or
antibiotic
resistance
in response
to
selection
12
Evidence for Evolution – Evolution Observed
Evolution of drug-resistance in HIV
13
Evolutionary
Time Scales
Macroevolution:
Long time scale
events that
create and
destroy species.
14
Evolutionary
Time Scales
Microevolution:
Short time scale
events (generationto-generation) that
change the
genotypes and
phenotypes of
populations
15
p. 34 – Biological Resistance – copy the following
questions, and leave spaces for your answers.
1. What do you think biological resistance is?
2. How do you think that the first pesticide
resistant tick got here?
3. How could this example of pesticide resistance
in ticks be similar to antibiotic resistance
among bacteria?
4. Is biological resistance an example of natural
selection or artificial selection?
16
Generation:
1
# of Drug
Resistant Ticks:
1
2
3
3
8
4
13
5
16
6
18
17
18
Biological Resistance
 Biological
Resistance:
resistance of a
microorganism
to a drug that
was originally
effective for
treatment of
infections
caused by it.
19
 Biological
resistance
happens
through the
overuse and
misuse of
drugs and
pesticides.
20
Speciation
The evolution of two or more
species from a common
ancestor
Coevolution
Two or more species evolve in
response to changes in each
other
21