A. Hypothesize the mode(s) of selection exerted by wasps on gall size of Eurosta. Explain your rationale. b. Hypothesize the mode(s) of selection exerted by birds on gall size of Eurosta. Explain your rationale. c. Hypothesize the mode(s) of selection exerted by beetles on gall size of Eurosta. Explain your rationale.

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.

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.

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.