The adaptive significance of leaf-mining pattern as an anti-parasitoid strategy: A theoretical study

Summary An adaptive significance of linear leaf mining patterns as the anti-parasitoid strategy is theoretically analysed. In the model, a leaf-miner is allowed to move in one of four ways; mining ahead in unexploited area of a leaf, backtracking, branching off from the backtracking mine, and crossing the previous mine. The model parasitoid searches for the leaf-miner by tracing the mine by the tactile cue of mine surface after detecting the mine. The average duration from detecting the mine to finding the leaf-miner host is calculated for various patterns of mining, changing numbers of branches and of crosses. This average duration becomes longer when the leaf-miner stays near either end of the mine compared with when staying near its center. It is also prolonged as the numbers of branches and of crosses increase.