How large should offspring be?

• Trade-off between number and size of offspring.

• Produce many small OR few large?

• Can be dictated by environmental context; i.e., the reproductive strategy may include phenotypic plasticity

• e.g. Stator limbatus (a seed beetle)

Seed beetle: Stator limbatus

Blue palo verde seedPoor host: < 1/2 larvae survive

Cat-claw acacia seedGood host: most larvae survive

Stator limbatusAssumption 1Size decreaseswith an increasednumber of sibs

Results 1Minimum size atwhich offspringsurvive is smalleron good host

Results 2Optimal offspringsize for parent islarger on poor host

Offspringsurvival

Parentalfitness

1st egg onone host -then femaleswitched toTte other host

Control