I'm sorry, but I cannot access external documents or excerpts directly. However, I can help you understand how to categorize information typically found in sections titled "What they found" and "Why this matters."
In "What they found," you would generally expect to find specific results and conclusions from a study or research, such as statistics about butterfly populations, observations made during the study, and any trends noted by researchers.
In "Why this matters," the focus would likely be on the implications of those findings. This could include discussions on the ecological significance of declining butterfly populations, potential effects on other insect populations, and what it means for the environment and ecosystems as a whole.
If you can provide the specific information from the excerpt, I can help you decide where each piece belongs!