What is the argument defendant for Reynolds v Sims?

In Reynolds v. Sims, the defendant argued that the existing apportionment of state legislative districts did not need to reflect population equality, claiming that historical practices and local interests justified the unequal representation. They contended that the Constitution does not mandate strict population-based representation, emphasizing the importance of maintaining a balance between urban and rural interests. The case ultimately focused on whether state legislative districts must adhere to the principle of one-person, one-vote to ensure fair representation.