This monarch family tree visualization is based from the data found here, so naturally similiar notations are being used :
How to use :
Use mouse to drag the tree. Use mouse scroll button to zoom in or out (or you can use the leftmost ‘Zoom’ button group). The ‘RESET’ button will reset tree positioning, zooming and overall view.
Hover on the nodes to view family member data. You can choose between ‘Simple’ or ‘Complex’ data when a person is highlight-ed. Use the searchbox to search a family member from the tree.
The rest of the buttons are self-explainatory.