A fig (Ficus obtusifolia) pictured with its pollinator wasp.
CHARLOTTE JANDER
Wasps and fig trees swap favors: the fruit serves as the insects' breeding grounds and the wasps pollinate the plants. Some fig tree species can discourage wasps that don't participate in the exchange by dropping unpollinated figs, destroying the larvae inside, according to the authors' report.
See K.C. Jandér et al., “Why mutualist partners vary in quality: mutation–selection balance and incentives to cheat in the fig tree–fig wasp mutualism,” Ecology Letters, doi:10.1111/ele.12792
