Intraspecific differentiation across a steep environmental gradient depends on the relative influences of evolutionary, organismal, and environmental processes. But steep environmental gradients may be nested within larger‐scale, regional conditions that could influence these processes at the local scale. Therefore, we hypothesized that phenotypic differentiation along a steep environmental gradient would vary among regions. To test this hypothesis, we conducted a reciprocal transplant experiment on rocky intertidal shores, a habitat characterized by gradients in abiotic and biotic stress, in three regions of the Gulf of Maine. We used the ubiquitous and ecologically important rockweed species
Intertidal seaweeds must cope with a suite of stressors imposed by aerial exposure at low tide, including nutrient limitation due to emersion. Seaweeds can access nutrients only when submerged, so individuals living higher compared to lower on the shore may have adaptations allowing them to acquire sufficient amounts of nutrients to survive and maintain growth. Using a combination of observations and experiments, we aimed to identify intraspecific variation in nitrate uptake rates across the intertidal distribution of
- NSF-PAR ID:
- 10246693
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Phycology
- Volume:
- 52
- Issue:
- 5
- ISSN:
- 0022-3646
- Format(s):
- Medium: X Size: p. 863-876
- Size(s):
- p. 863-876
- Sponsoring Org:
- National Science Foundation
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