I think it’s fair to say we can safely infer from the numbers in the hobby that having a light cycle doesn’t disturb the circadian rhythm of ball pythons in any way we could measure, whether light or dark. I’ve seen what happens in several different types of galliformes when exposed to 24 hour light cycles and the decline is rapid and obvious.
If I was disturbing their rhythm by using clear tubs and having a window in the room, I would have noticed many years ago. My females are clockwork when it comes all expected behaviors. With the tools we have in the hobby you could not measure a difference in how ball pythons thrive either with or without a light cycle.
Something that likely plays into this in some way is that ball pythons eyes are designed to perceive UV light in some fashion. In morelia it is accepted that they use that UV perception to follow pheromone trails. Anecdotally I can say it appears to be the same for ball pythons.
On my property a few years ago I built the ‘snake circle’ which is a 20’ circle of woven manzanita branches under the shade of a large elm. There are lots of hides, different substrates, unlimited opportunities to climb, etc. I frequently start ‘gym class’ sessions by allowing one or two females to crawl around first. Much more frequently than I would have ever expected I see scenting behavior, especially from the females. They typically spend the first several minutes moving with their tail curled forward while crawling, scenting. If I place a receptive male on the ground after removing the females, often he will follow the female’s path directly to her first hide. Often it’s easiest to spot with younger females that still are inclined to semi-arboreal behavior, since males will climb to the exact nest of branches where a female had previously been resting. Anecdotal, yes, but I’m fairly certain that what I’m seeing is pheromone trailing and it seems likely that it is visually cued. This all happens in broad daylight
This a great paper, but please understand that to further research, animals are often euthanized for proper examination and data collection.
Photoreceptors and Visual Pigments in the Retina of Ball Pythons
Edit to add link to this paper:
Effects of UV light on Calcium Metabolism in Ball Pythons