Homeostasis theory: What can we learn from dormancy and symbiotic associations?
Résumé
In this letter, I discuss the notion of dormancy that De Luca Jr. relies on to criticize the theory of homeostasis. In particular, I try to qualify the issues related to the fact that dormancy is not always a free behavior but is in most situations under the influence of environmental factors. To this end, I discuss diapause in arthropods, which can be obligatory (under the influence of endogenous commands) but which is in most cases facultative (under external command). I emphasize that the notion of stability of a dormant organism must be taken with caution. I briefly mention what the study of sleep in animals can contribute to the notion of homeostasis. Finally, I focus on the role of microbial symbionts and the notion of holobiont. Through this, I question the future of the notions of internal environment and homeostasis and I propose to revisit them in the context of the effects of species in-teractions on the physiology of organisms.