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Default (“safety net”) guide to lighting periodicity.
| Natural habitat type | Natural lifestyle type | Periodicity | |
|---|---|---|---|
| Daytime (h) | Nighttime (h) | ||
| Open habitat | Diurnal | 12–16 | 8–12 |
| Crepuscular (phased transition) | 4 | 4 | |
| Nocturnal | 12 | 12 | |
| Closed habitat | Diurnal | 12 | 12 |
| Crepuscular (phased transition) | 4 | 4 | |
| Nocturnal | 12 | 12 | |
