Luna Moth

Summer is fast approaching. Weather went from early spring drizzle (40's and 50s) and drab to suddenly summer (mid-80's). It is Memorial Day weekend. The mostquitoes are back, the dragonflies are back. The luna moths are transformed into their emerald green. I put on the bug zapper to attract the moths. When we got home from visiting family, there was a small one on the living room screen. I always look forward to seeing them again.
Two yellow tail butterflies expired on the driveway. Why? I moved them aside and a third one came to check out the temporary morgue. Another why?