The researchers wanted to see if a certain insect, Neoplea striola, could cause a ripple effect in small warmwater ponds without fish. They collected plankton from ponds in Texas, put them in controlled environments, and added different amounts of Neoplea. They found that the insect didn't have a strong impact on the food chain, except for a slight decrease in large phytoplankton. This suggests that trophic cascades might not be very common in ponds without fish and with rare Daphnia.