When I use the Eraser Tool (Shift+E) in Illustrator, there is a strange and undesired effect. It seems to clean up fine details on the effected layer, sometimes removing small shapes. For example, here are some small shapes (these are fine details, note the zoom is at 1600%).
Now I click the eraser on the top-rightmost white shape, with a brush size just large enough to cover it: All but the biggest shape is gone!
Why is this happening and what can I do to prevent it?