The scientists studied the benthic macroinvertebrates in Sangi Stream, Izmir, Turkey, to see what kinds of creatures live there. They found four main groups of benthic macroinvertebrates: Crustacea, Oligochaeta, Gastropoda, and Insecta, with insects being the most common. This was the first time all these creatures were identified in the stream. The researchers collected samples monthly for over a year and used different methods to analyze the diversity and species composition of the benthic macroinvertebrates.