Life Tables

1
Life Tables

• Ricklefs Miller (1999) Ecology
• Age Structure
• Stable Age Distribution
• Life Table Environmental Dependence

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Stable Age Distribution
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Vital Rates Environment
4
Experimental Population Dynamics

• Costantino et al. 1995. Experimentally induced
  transitions in the dynamic behaviour of insect
  populations. Nature 375227.
• Flour beetle Tribolium castaneum
• Manipulate Adult Mortality Bifurcation

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Flour beetles

• Grown in ½ pint milk bottles
• Change media (food) every 2 weeks
• Census all stages
• Add or remove adults mortality rate

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Flour beetles

• Multiple stages egg, larvae, pupae, callow
  adults, mature adults
• Consume media cannibalism
• Larvae adults eat eggs
• Adults eat pupae

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Dynamics (Skeleton)

• Lt Feeding Larvae, time t
• Pt Pupae, time t
• At Mature Adults, time t
• (t 1) 2 weeks later

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Dynamics
b larvae per adult before cannibalism cij
cannibalism of stage j on stage I ?j mortality
of stage j
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Stability boundaries, 3 genetic strains
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Stability boundaries, 2 test genetic strains
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Experimental results, RR strain
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Experimental results, SS strain
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Experimental Population Dynamics

• Costantino et al. 1995. Experimentally induced
  transitions in the dynamic behaviour of insect
  populations. Nature 375227.
• Dynamics Bifurcate as Model Predicts