I am looking for help (and possibly references) regarding the correct mapping of time in a cladogram. As far as I know, it is considered incorrect to draw a time axis diagonally in a cladogram as shown below:
This setting would lead to conclusions like: Species B and ancestor b lived at the same time, because they would both fall upon the same place on the time axis. But we know this is incorrect. Or is this an acceptable positioning for a time axis?
The image below correctly represents the time axis, if I'm not wrong, using a vertical axis.
This positioning makes it clear that species B and b are not living at the same time. In this case, species B is alive and b is an extinct ancestor.