Transcript Document

Ch. 5: Population
Structure and Changes
Ch. 5: Population
Structure and Changes
Population Models
• 4) Transition matrix models
• Life history stages + matrix algebra
Fig. 5.6
Population Models
• Matrix algebra
• Matrix: numbers rows/columns
– Rules (adding, multiplying, etc.)
Population Models
• Ex: Column matrix (vector) = pop’n status: population
vector
• Life history stages: s=seeds, r=rosettes, f=flowering
140
# seeds
16
# rosettes
10
# flowering
Population Models
• Transition matrix:
probability transition b/w
1 census & next
Population Models
• Ex: teasel (Dipsacus sylvaticus)
• Perennial pasture/roadside weed.
Population Models
• Transition matrix: teasel (Dipsacus sylvaticus)
Note columns don’t always sum to 1.0: accounts for mortality
Population Models
• Model: pop’n vector X transition matrix
• New matrix: pop’n structure next time
Population Models
• Ex: 3 stages. Seed, rosette, flowering
• Pop’n vector
140
# seeds
20
# rosettes
10
# flowering
Population Models
• Ex: 3 stages. Seed, rosette, flowering
• Transition matrix
year 1
seed
year
2
rosette
flowering
seed
0.5
0
20
rosette
0.2
0.2
0.2
flowering
0
0.5
0.1
Note: columns not summing to 1.0 includes mortality
Population Models
• Ex: 3 stages. Seed, rosette, flowering
• Next year’s pop’n.? Multiply.
s
140
s 0.5
r
fl
0
20
20
X r
0.2
0.2
0.2
10
fl
0
0.5
0.1
270
70 + 0 + 200
=
28 + 4 + 2
0 + 10 + 1
=
34
11
New
Pop’n
Vector
Model Summary
• 1) Explore changes (seedling survival, etc.)
• 2) Future managed pop’ns
PVA
Model Ex: Florida Torreya
• Rare conifer (Torreya taxifolia)
• Steep ravines: Apalachicola River
Florida Torreya
• Population viability analysis (PVA)
– Models predict extinction
Ch. 6: Evolutionary Processes/Outcomes
Plants and Environment
• Plant/environment interactions
• 1) Liebig (1840)
– German agriculturist
– Discovered mineral fertilizer
Plants and Environment
• 1) Liebig (1840)
– Law of the Minimum: Growth/distribution
depends on environmental factor most limiting
A Festive MoB CuMnZn Clapping Nicely
Plants and Environment
• 1) Liebig (1840)
– Australia legumes (soil
deficient Mo)
– 13 oz/acre every 5-10 yr
increased yield 600700%
Plants and Environment
• 2) Shelford (American:
early 1900s)
– Upper limits for factors
– Proposed “Theory of
Tolerance”
– Abiotic factors define
“potential range”
Plants and Environment
• 2) Shelford (American: early 1900s)
– “Physiological” or “potential” optimum: best
point for growth
Plants and Environment
• 2) Shelford (American: early 1900s)
– Biotic factors: give actual (ecological) range
and optimum
– Ex, add
Plants and Environment
– Ex: Klamath weed (Hypericum perforatum) from
Europe
– Cattle avoid
Plants and Environment
– Chrysolina beetle (biocontrol)
Plants and Environment
– Chrysolina beetle (biocontrol)
– Grows only in
Plants and Environment
• Phenotype: appearance
• Genotype: genetic make-up
• Phenotype: determined
Plants and Environment
• Equation:
• Vp = Vg + Ve
• Vp = total
• Vg = variation due to
• Ve = variation due to
Focus Vg
Plants and the Environment
• Adaptation: What is an adaptation?
Plants and the Environment
• Adaptation:
– 1)
– 2)
• How determine trait adaptation? Hard!
Genetic importance