Worn-out wings

Bees' wings suffer a lot of wear and tear during their brief lives and as they fly through the vegetation their beating wing tips often touch plants and become split and broken.

The wing tips of this bee, feeding on rampion Phyteuma nigrum flowers are almost completely worn away ...

... as are those of this one, feeding on green alkanet Pentaglottis sempervirens. 

The loss of wing area must mean that these bees need to work a lot harder to stay in the air.