Two bees (or maybe one bee and a flower fly, perhaps?) vying for pollen on one small sunflower. See the fella on the right? Look at how thick the pollen is on his body and legs!
UPDATE: I recently received this comment below from a viewer. Thanks for the identification—I learn something new every day!
Nice photo. The one on the right is a female bee. The males don’t carry pollen on their back legs; in the world of bees the females do all the work. The one on the left is a flower fly, Eristalis; it is a male. You can tell because of its huge eyes.
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Garden Muse 
Step right up. All you can slurp! Yummy for the pollinators.
Nice photo. The one on the right is a female bee. The males don’t carry pollen on their back legs; in the world of bees the females do all the work.
The one on the left is a flower fly, Eristalis, it is a male. You can tell because of its huge eyes.