The link in your post appears to be broken, but I found this article. It appears these are apparently globe mallow bees sleeping in globe mallow flowers. But other bees sleep as well, although not necessarily in flowers.
In the fall, we have bumblebees sleeping in our sunflowers all the time. The temperature drops, and they get sleepy. And when the morning sun hits, off they go.
Yes, just like with humans, when bees are not at work they sleep.
This is usually at night when darkness prevents them from gathering pollen.
I guess if they get tired they might take a nap.
thanks for sharing the sleeping bees images.
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