You'll first have to move one of the nodes to the side to expand the food web. You can highlight nodes and see connections that extend 3 degrees away from the node.
Link to fullscreen To remove nodes, select a node and then click "Edit" in the top left corner and select "Delete selected". To add nodes, click "Edit" in the top left corner and then select "Add Node", click to place, and then add a name. To add connections among nodes, select a node and then click "Edit" in the top left corner and select "Add edge" and drag click between nodes that you would like to connect.