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Title: Life Ascending: Mechanism and Process in Physiological Adaptation to High-Altitude Hypoxia
To cope with the reduced availability of O 2 at high altitude, air-breathing vertebrates have evolved myriad adjustments in the cardiorespiratory system to match tissue O 2 delivery with metabolic O 2 demand. We explain how changes at interacting steps of the O 2 transport pathway contribute to plastic and evolved changes in whole-animal aerobic performance under hypoxia. In vertebrates native to high altitude, enhancements of aerobic performance under hypoxia are attributable to a combination of environmentally induced and evolved changes in multiple steps of the pathway. Additionally, evidence suggests that many high-altitude natives have evolved mechanisms for attenuating maladaptive acclimatization responses to hypoxia, resulting in counter-gradient patterns of altitudinal variation for key physiological phenotypes. For traits that exhibit counteracting environmental and genetic effects, evolved changes in phenotype may be cryptic under field conditions and can only be revealed by rearing representatives of high- and low-altitude populations under standardized environmental conditions to control for plasticity.  more » « less
Award ID(s):
1736249
PAR ID:
10179132
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Annual Review of Ecology, Evolution, and Systematics
Volume:
50
Issue:
1
ISSN:
1543-592X
Page Range / eLocation ID:
503 to 526
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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