Baldness pattern!

I'd take a guess at either meds or age.
Once you reach a certain age (52-60?) your body produces less testosterone resulting in decrease of DHT, sometimes sufficient to not harm the haircells anymore.

This is something I've wondered myself. I've known a couple people who were obviously balding but seemed to stop at a certain point and progress no further. I guess it just all comes down to genetics.

Did any of you happen to catch SNL last night. They had some of the original cast- Dan Aykroyd and Chevy Chase. I remember when D.A. first started going bald- as in visible bald spot as I had just begun to lose temple hair myself.
This was like way back in '83 -30 years ago. ASFAIK he has never done anything to try and hide it or fight it.

Well 30 years later his bald spot is certainly bigger, but the fact that he has not lost the rest of his hair after 30 years shows that mpb can sometimes be very slow. Probably genetics like you said.

I don't remember when C.C. started losing his hair but it was a long time ago as well. He is a little further along that D.A. but still has some hair.