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ABSTRACT Physiology defines individual responses to global climate change and species distributions across environments. Physiological responses are driven by temperature on three time scales: acute, acclimatory and evolutionary. Acutely, passive temperature effects often dictate an expected 2-fold increase in metabolic processes for every 10°C change in temperature (Q10). Yet, these acute responses often are mitigated through acclimation within an individual or evolutionary adaptation within populations over time. Natural selection can influence both responses and often reduces interindividual variation towards an optimum. However, this interindividual physiological variation is not well characterized. Here, we quantified responses to a 16°C temperature difference in six physiological traits across nine thermally distinct Fundulus heteroclitus populations. These traits included whole-animal metabolism (WAM), critical thermal maximum (CTmax) and substrate-specific cardiac metabolism measured in approximately 350 individuals. These traits exhibited high variation among both individuals and populations. Thermal sensitivity (Q10) was determined, specifically as the acclimated Q10, in which individuals were both acclimated and assayed at each temperature. The interindividual variation in Q10 was unexpectedly large: ranging from 0.6 to 5.4 for WAM. Thus, with a 16°C difference, metabolic rates were unchanged in some individuals, while in others they were 15-fold higher. Furthermore, a significant portion of variation was related to habitat temperature. Warmer populations had a significantly lower Q10 for WAM and CTmax after acclimation. These data suggest that individual variation in thermal sensitivity reflects different physiological strategies to respond to temperature variation, providing many different adaptive responses to changing environments.
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Investigating User Experience of On-Body Heating Strategies in Indoor Environments
Thermal physiology and psychophysics are complex and nuanced, with significant variability between individuals. Wearable devices have the potential to offer customizable microclimate control. However, individual experiences with different supplemental heating strategies are likely to vary considerably in unconstrained environments. The physiological responses, psychophysical effects, and qualitative experiences of participants using five readily available heating strategies were collected in a quasi-field study environment ( n=17). Although all devices maintained or increased fingertip temperature, effects observed from controlled studies of thermal physiology are not clearly seen. Physiological, perceptual, and experiential data are presented, exploring heating technologies and thermal comfort in typical indoor environments.
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- Award ID(s):
- 1646543
- PAR ID:
- 10337009
- Date Published:
- Journal Name:
- Ergonomics in Design: The Quarterly of Human Factors Applications
- ISSN:
- 1064-8046
- Page Range / eLocation ID:
- 106480462210787
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1177/10648046221078720
