Inuenced by survival rate life history theory when

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Unformatted text preview: ; future reprod. influenced by survival rate Life History Theory: when will selection favor which side of the balance? offspring number vs offspring quality early reproduction vs. late reproduction Selection on life histories: risk of predation in guppies size at maturity low pred.: larger size investment / reproduction event above waterfalls: low predation below waterfalls: high predation offspring # lower investment high pred.: smaller size higher investment offspring size fewer, larger offspring more, smaller offspring Selection on life histories: risk of predation Cod Commercial fishing: take large numbers of the oldest/largest individuals; select for early maturation (at smaller sizes) Selection on life histories: risk of death Tasmanian devils: lifespan 5-6 years; females begin breeding at age 2; 1 litter/yr epidemic of contagious tumors: tumors affect adults; kill within months; before: 75% of females bred 1+ times; after: 35% of females bred 1+ times Prediction: reduced adult survival wil...
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