Information Determines the Optimal Clutch Sizes of Competing Insects: Stackelberg Versus Nash Equilibrium

When two insects oviposit on the same host, their abilities to detect the other femaleʹs clutch and assess its size crucially determine their optimal clutch sizes. If detection is impossible, the optimal clutch sizes are simply found by pure maximization, and if only size assessment is impossible, they are a Nash equilibrium pair. This paper compares these optimal clutch sizes with the ones when size assessment is possible. In this case, the optimal clutch sizes are a Stackelberg equilibrium pair, which gives different predictions. We derive under which conditions the competition between the females results in an increase in the first femaleʹs optimal clutch size, compared to the solitary optimum. Furthermore, we derive under which conditions the first female should lay more eggs than the second female.