A media application of some embodiments includes a timeline, which is a composite display area for displaying media clips that are part of the composite media presentation. The timeline of some embodiments includes a primary lane called a spine as well as one or more anchor lanes. The spine represents a primary sequence of media, which, in some embodiments, does not have any gaps. When a clip is deleted or removed from the timeline, the media-editing applications automatically closes the gap created in place of the clip. The clips in the anchor lanes are anchored to a particular position along the spine. Anchor lanes may be used for compositing (e.g., removing portions of one video and showing a different video in those portions), B-roll cuts (i.e., cutting away from the primary video to a different video whose clip is in the anchor lane), audio clips, or other composite presentation techniques.