Deleting lifelines from UML diagrams

You can delete lifelines from UML diagrams, such as sequence or communication diagrams, to remove an object from an interaction. When you delete a lifeline, all send and receive messages that originate from the deleted lifeline are also deleted. When you delete a lifeline from a sequence diagram, all interaction fragments that cover the lifeline are deleted, but the combined fragments and interaction uses that cover other lifelines are not.