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Stress responses are conserved physiological and behavioral outcomes as a result of facing potentially harmful stimuli, yet in pathological states, stress becomes debilitating. Stress responses vary considerably throughout the animal kingdom, but how these responses are shaped evolutionarily is unknown. The Mexican cavefish has emerged as a powerful system for examining genetic principles underlying behavioral evolution. Here, we demonstrate that cave Astyanax have reduced behavioral and physiological measures of stress when examined at larval stages. We also find increased expression of the glucocorticoid receptor, a repressible element of the neuroendocrine stress pathway. Additionally, we examine stress in three different cave populations, and find that some, but not all, show reduced stress measures. Together, these results reveal a mechanistic system by which cave-dwelling fish reduced stress, presumably to compensate for a predator poor environment.
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This content will become publicly available on June 1, 2026
Environmental complexity, cognition, and plant stress physiology
Facing stress and producing stress responses are crucial aspects of an organism’s life and the evolution of both its species and of the other species in its environment, which are co-evolving with it. Philosophers and biologists emphasize the importance of environmental complexity and how organisms deal with it in evolution of cognitive processes. This article adds to these discussions by highlighting the importance of stress physiology in processes connected to plant cognition. While this article supports the thesis that life means cognizing (i.e., sensing the environment, arranging internal processes according to that perception, and affecting the environment with its actions), it also emphasizes that there are various kinds of organisms. In this regard, plant cognition is not animal cognition. However, given both the variety and continuity in evolutionary processes and the similarities even between the distantly related organisms in the tree of life, I argue that it is usually useful to consider and compare physiological and molecular mechanisms in plants and animals as well as the concepts and research processes in animal and plant science. Although the “pathological complexity” thesis that Veit (2023) presents is fruitful in considering the evolution of consciousness and cognition, I argue that, when thinking of biological processes in relation to cognition, stress can be a helpful concept (maybe even as suitable as pathological complexity) in thinking of organisms’ responses to environmental complexity and their adaptation and acclimation processes.
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- Award ID(s):
- 2240749
- PAR ID:
- 10632681
- Publisher / Repository:
- Adaptive Behavior
- Date Published:
- Journal Name:
- Adaptive Behavior
- Edition / Version:
- https://doi.org/10.1177/10597123241278799
- Volume:
- 33
- Issue:
- 3
- ISSN:
- 1059-7123
- Page Range / eLocation ID:
- 183 to 188
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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