According to Gun, Germs and Steel, what is one important impact of domesticating animals on the relationships between people in society regarding...

The answer to this can be found in Chapter 14 of the
book.  There, Diamond discusses the relationship between food production and the
creation of states.  He argues that food production (of which domesticating animals is a
part) changes the relations between people and helps to lead to state
formation.

When people domesticate crops and animals, their
societies change.  Perhaps the most important change is that the size of the society
increases.  Before food production, people were largely living in bands whose members
were bound to one another by ties of kinship or at least friendship.  Once food
production begins, however, these ties are loosened.  As the size of the population
grows, the bonds between members erode.  All of a sudden, people are living in close
proximity to others who are not kin and may not even be friends.  This necessitates a
completely new way of living.  It creates a need for laws and authority to prevent the
unrelated people from (in extreme instances) killing one
another.

In this way, domesticating animals (along with
other forms of food prodution) increases the size of a society and forces people to find
ways to live with unrelated people.  This leads to the need for laws, authority and
government.  This is the beginning of the road to state
formation.