How would you represent "changes" in an icon?

I've come across a challenge. I need to design an icon representing "changes". Well actually two closely related icons, both representing "changes" but distinguishable from each other:

1. "Change tracking" - the process itself, the ability to view change history.


2. "See what happened while you were away" - a summarized overview of changes made by others since last logon.

What associations do you guys have that are the closest to these meanings?