Well hello again Nigel! Welcome back to PD. 
Thanks!
wow. That’s a lot of really interesting stuff that is weirdly relevant to me! (I could probably be a damned case study in your epigenetics thing, and maybe unrelatedly???my sleep cycle is so broken that I just last night double-dosed on sedatives and only slept two hours despite desperately aiming for 7+.)
Anywhere you’re putting any of this out, or is it more of a general research (as opposed to scientific or academic) or saving for publication sorta deal right now? I’d love to read more about it all, as I said, it’s almost creepily relevant to my life.
My first incredibly boring paper on circadian-relevant hormonal pathways will be published as a collaboration sometime next year, but since I just transitioned from basic research to epidemiology last Fall, it's gonna be a while before any of my current work is published. In the meantime, this paper may be of interest to you (let me know if you're unable to access it and I'll see if I can find a version that isn't behind a paywall, it's not always clear whether it's paywalled or not on my end):
https://www.ncbi.nlm.nih.gov/pubmed/31026301Hey, Nigel, awesome! If you ever want to talk to someone with severe social deficiencies, assloads of developmental stress as well as a tendency to go nocturnal, pm me.
Sounds like a laugh riot!
Seriously though, one of the reasons I'm so interested in this topic is that these issues you are experiencing are pervasive and increasing in our society. We tend to assume that health is driven by behavior, and it's just that in my behavioral neuroendocrinology training I started to see things the other way around.
I took last week off work to attend gardening horticulture classes at the local university, and one day I partook of a tour of the agriculture greenhouses.
At one point, the tour guide was showing off a greenhouse equipped with shades, and recounted how a researcher was having trouble getting a particular set of plants to flower, until she noted that the plants originated from Ecuador. So, they used the shades to produce a 50% day/night cycle, and the plants began flowering. (These greenhouses are above 52° N. Equal length days and nights aren't something we do here).
It would be interesting if individual (human) reactions to photoperiod was partially dependent on geographic origin. After all, lighter skin colour appears to be an adaptation to the amount of sunlight.
That is a very interesting question, and I wouldn't be surprised if that is true. After all, circadian clock programming is determined partially through DNA methylation, and differential DNA methylation may occur during pregnancy, priming the fetus' wake-sleep rhythms to match the mother's. Interestingly, the time of day you are born matters; night babies are at higher risk for bipolar disorder and schizophrenia than day babies, and there is evidence of circadian disruption in both those diseases.
One thing to keep in mind is that there is nowhere on earth a 16/8 photoperiod occurs naturally year-round.
