The little orange creatures are Lasius ants, sometimes called Citronella ants because of their lemony smell. The white creatures are aphids which feed on the roots of plants. Both of these species spend almost all their lives underground. This is why the aphids are white, like many cave-dwelling critters who have lost pigmentation. The ants have tiny little black dots for eyes, signalling that they too spend most of their time in dark places where eyesight is not an important sense. I found them by turning over a rock under which were many tunnels into which they retreated.

The ants of course, are tending the aphids because they relish the 'honeydew' the aphids secrete. In turn, the aphids are protected by the ants.

For other scavengers: http://form.pbase.com/viewtopic.php?f=16&t=45310