Odd looking bee?
Thank you for your message with attached image and for contacting Iowa State University. You are correct; the insects in your photos are dung flies. Flies have two wings; bees have four wings and long antennae.
Dung flies are predators that feed on other insects. The larvae live in dung and other decaying organic matter.
Here is a link to more information: http://bugguide.net/node/view/8320