Answer:
The induction of galls in plants represented both morphological and physiological modifications of plant organs and tissues caused by endophage insects.
In the case of wasps, the relationship they have is of parasitic coexistence, therefore the gills become smaller.
On the other hand, with birds the relationship is different since sometimes they usually feed on gills, their size is larger.
As for beetles, the size is intermediate.
Step-by-step explanation:
The natural selection and the environment of the gills is what makes the size of said living being, this theory can be explained by means of the principles that Darwin proposed with the evolutionary theory.