Download Danthonia spicata Impatiens capensis

Panglossian
Gould and Lewontin 1979
After the character Dr. Pangloss In the novel Candide by Voltaire
“ All is for the best in this, the best of
possible worlds”
Evolutionary change
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•
•
•
Natural Selection
Mutation
Migration of individuals
Genetic drift
Natural selection
• Phenotypic variation
• Genetic
• Environmental
• Developmental
• Fitness differences
• Heritability
• Fitness: Fecundity, Fertility, Survivorship,
Directional selection
Danthonia spicata
Impatiens
capensis
Stabilizing selection
Ipomoea purpurea
Cakile endentula
Heritability (h2)
Brassica
campestris
VP=VE+VGxE+VG+Cov(G,E)+Ve
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•
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VP Phenotypic variation
VG Genetic variation
VG=VA+VD+VI ;(additive, dominance, epistatic)
VE Environmental variation
VGxE Genotype-environmental interactions
Cov(G,E) Gene environment covariation
Ve errors in development
Heritability
• h2=Gg/Ve
Processes that increase variation
• Mutation
• Recombination
• Migration
Processes that decrease variation
• Natural selection
• Genetic drift
VP=VE+VGxE+VG+Cov(G,E)+Ve
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•
•
•
•
•
•
VP Phenotypic variation
VG Genetic variation
VG=VA+VD+VI ;(additive, dominance, epistatic)
VE Environmental variation
VGxE Genotype-environmental interactions
Cov(G,E) Gene environment covariation
Ve errors in development
Have-metal Tolerance
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•
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Bradshaw 1970
Zinc and Copper
Anthoxanthum odoratum and Agrostis tenuis
Trade offs
First: Demonstrate all three components of
natural selection
• Second: secondary predictions were also met
(pollination)
• Third: Occurred in several places
Ceratiola ericoides
occupied
un-occupied
0
500
Meters
1,000
Ceratiola ericoides
Drupe with two (sometimes three) seeds
40
30
50
20
40
10
Std. Dev = 6.30
Mean = 48.9
30
N = 134.00
0
32.5
37.5
35.0
42.5
40.0
47.5
45.0
52.5
50.0
57.5
55.0
62.5
60.0
20
Fruit length
10
Std. Dev = 5.61
Mean = 45.3
N = 134.00
0
32.5
37.5
35.0
Fruit width
42.5
40.0
47.5
45.0
52.5
50.0
57.5
55.0
60.0
40
30
20
10
Std. Dev = 5.88
Mean = 60.1
N = 134.00
0
45.0
50.0
47.5
Seed length
55.0
52.5
60.0
57.5
65.0
62.5
70.0
67.5
72.5
80
60
40
20
Std. Dev = 4.77
Mean = 46.3
N = 134.00
0
20.0
25.0 30.0
Seed width
35.0
40.0 45.0
50.0 55.0
60.0
80
70
60
50
40
40
Rsq = 0.4389
60
50
Seed length
70
Large fruits
Small fruits
30
14
12
10
20
8
6
10
4
Std. Dev = 5.74
Mean = 61.7
N = 84.00
0
45.0
50.0
47.5
55.0
52.5
60.0
57.5
65.0
62.5
Std. Dev = 5.08
2
70.0
67.5
Mean = 57.3
N = 50.00
0
45.0
72.5
50.0
47.5
Seed length
55.0
52.5
60.0
57.5
65.0
62.5
70.0
67.5
72.5
Seed length
Large fruits
Small fruits
50
30
40
20
30
20
10
10
Std. Dev = 5.06
Std. Dev = 3.76
Mean = 47.3
N = 84.00
0
20.0
25.0 30.0
Seed width
35.0
40.0 45.0
50.0 55.0
60.0
Mean = 44.7
N = 50.00
0
20.0
25.0 30.0
Seed width
35.0
40.0 45.0
50.0 55.0
60.0
Plasticity
• Impatiens capensis (Schmitt and colleagues)
• The elongation is controlled by the ratio of red to
far red light
Suppressed sun, high ratio
Elongated, shade, low ratio
High
Low
Geranium sanguineum