They are actually much more similar than most people realize. However, people usually burn more calories total on cycling because it's easier to put longer time periods into cycling than it is for running.

Put another way, an average cyclist will find a 2 hour bike ride to be an average ride but an average runner will consider a 2 hour run to be quite long.

As much as I enjoy cycling, I don't have anywhere near enough time to accommodate a bike regimen equivalent to my running regimen. To my mind, the only way cycling comes out ahead of running for most people is if (1) they have an usual amount of free time (e.g. enough to go on three hour rides every day), or (2) they're unable to run without injuring themselves.

Jogging is very efficient, mechanically speaking. You're not going to burn a lot of calories per hour.

You need to put more effort in 1 hour cycling session to burn the same amount of calories as in 1 hour running session. Running activates more muscles.

But cycling affects largest human muscles, which work more intensively..

I was "professional" athlete many moons ago. When we measured max heart rate, we did it on a bike first and then on a treadmill running and then bike again. My max heart rate running was +5 beats allways and I was not a single case. I just couldn't get to my max heart rate while cycling.

Depends on how you look at it. I can bike all day without getting tired, but there's no way I can jog all day. If your definition of efficiency includes duration of effort, or distance covered, then cycling is very efficient.