An international network of/for intelligent organisms
Could you provide a closer view ? (macro) please ?
Isn't it some kind of this :
You left it in the light for too long, it's made spores - end of life cycle :(
This experiment was in my garage, with all the lights off. Did the occasional opening of the garage door and putting lights on to check on it effect this?
Most likely not. Slime mold can definitely sustain short periods of observation under light. The slime mold plasmodium looks really white on that picture, sign of its waste product traces as François-Joseph Deminiere's answer in this thread suggests. Maybe it grew really fast in the petri dish, and didn't find the right environment outside of the dish (not enough humidity)? Was the box the petri dish was in closed or left open?