I had pile of eggs sitting outside that I pulled from my pens a couple weeks ago and I kept forgetting to throw them away. Tonight, as I'm putting up my feed bucket I hear peeping... it was coming from the pile of eggs. Upon closer inspection, one egg was half zipped and another was pipped. Granted it's hot (and humid), but it certainly hasn't been anywhere close to consistent. Night time temps still get down to the low 80's or cooler. I candled the rest and found another that I can see movement in so I threw all three of them in the hatcher. I imagine they started to incubate under a hen for the first few days but even then, I wouldn't have expected them to continue growing and to hatch sitting out in the open air with the day/night temp fluctuations. Kind of makes you wonder if we aren't putting too much effort into keeping temps in our incubators exact.