We had an interesting discussion on sleep, where the context was fruit fly (Drosophila). what is sleep in fruit flies? How do we define sleep? Do microbes or rotifers sleep? Cubists also made one design to verify the hypothesis: fruit flies do sleep.
In order to be considered sleep-like, an inactive state should have the following features (6, 16): (1) consolidated circadian periods of immobility, (2) a species-specific posture and/or resting place, (3) an increased arousal threshold (although the state can be reversed by intense stimulation), and (4) a homeostatic regulatory mechanism.Joan CHendricks1*Stefanie MFinn1Karen APanckeri1JessicaChavkin1Julie AWilliams1AmitaSehgal1Allan IPack1
Sleep is also present in invertebrates, and an extensive analysis in Drosophila melanogaster has shown that sleep in fruit flies shows most of the fundamental features that characterize sleep in mammals.Sleep and wakefulness in Drosophila melanogaster https://pubmed.ncbi.nlm.nih.gov/18591491/
We determined that SCFA-attractive responses depend on two larval exclusive chemoreceptors, Or30a and Or94b. Of those SCFA, propionic acid improves larval survival in suboptimal rearing conditions and supports growth. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5660182/