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.
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.
Answer:
a. Modes of selection exerted by wasps: directional (positive) and stabilizing
If the galls are small in size, wasps are able to penetrate through and easily feed off of it. Hence, an average or large gall size of Eurosta is more likely to survive.
b. Modes of selection exerted by birds: directional (negative) and stabilizing
Birds will get attracted to large sized galls. Hence, the average and smaller sized galls of Eurosta are more likely to survive
c. Mode of selection exerted by beetles: disruptive
Beetles favor feeding on the average sized galls of Eurosta. Hence, the two extreme sizes - small and large galls of Eurosta - are more likely to survive. This will give two peaks if allele frequencies are plotted on a graph.
