The water bottles would become the temperature of the air around them...so if the incubator is set to 90, they would be 90...if the power was lost and the air around them dropped to 85...they would emit heat and neutralize the air temps for a while at least...keeping the air warm for a bit.
They might survive. Like the person below me said, you'll know in a week.
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"What is man without the beasts?
If all the beasts were gone,
men would die from great loneliness of spirit.
For what happens to the beasts,
soon happens to men.
All things are connected."
-Chief Seattle (Duwamish Tribe)