Why are swallows and swifts a like?

Swallows and swifts are alike primarily due to their similar body shapes and aerial feeding habits. Both belong to the order Apodiformes and are adapted for life in the air, featuring long wings and streamlined bodies that allow for agile flight. They predominantly feed on insects while flying and are known for their acrobatic flying skills. Additionally, both birds often nest in colonies and exhibit social behaviors, enhancing their similarities.