I've been trying to take notice of other bee species besides the usual European honeybees. One variety I've seen a lot around the sunflowers is the long horned kind, from the tribe Eucerini. Just a bit smaller than a honeybee, but the males have these long antennas.
I like this picture because it shows how the sunflower is actually made up of lots of tiny little flowers.
One interesting thing about these bees is that the males will sleep together in a cluster, nicknamed a "bachelor party". I saw some last year like this for the first time.
I haven't learned yet where the females sleep, if they have a hive or what.