Fragmentation modes and the evolution of life cycles
Fig 7
Optimal life cycles under monotonic survival landscapes.
Death rates are given by di = M(1 − gi) where gi = [(i − 1)/(n − 2)]α. A Costless fragmentation, n = 20. B Fragmentation with proportional costs, n = 21. C Fragmentation with fixed costs, n = 21. For costless fragmentation and fragmentation with proportional costs, only binary modes 19+1, 18+2,…, 10+10 are optimal. In these cases, diminishing returns to scale (α < 1) make equal binary fragmentation (10+10) optimal. Also, optimality of the unicellular propagule strategy (19+1) requires increasing returns to scale (α > 1). For fragmentation with fixed costs, nonbinary modes 7+7+6,…,1+…+1 can also be optimal.