Aqualia

Merfolks and land people had similarities. Yet, they were different all the same. Merfolks could manipulate their outer structure to adapt to their surroundings. Therefore, we could appear as land people in their world. However, land people could not do the same in ours. Our respiratory systems were also different. Though land people could survive minutes underwater by holding their breaths, they could not outdo merfolks, who could go days out of the ocean water. 

According to human biology, merfolks were the superior species. We didn't destroy our home and endanger other species. Even though we could be considered predators, we didn't start wars with other species or hunt them for fun. 

Let me not even mention our coupling organs, or what this biology book called sex organs. Land people had no shield or covering for their coupling organs. How insane