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Abstract Flowering phenology can vary considerably even at fine spatial scales, potentially leading to temporal reproductive isolation among habitat patches. Climate change could alter flowering synchrony, and hence temporal isolation, if plants in different microhabitats vary in their phenological response to climate change. Despite the importance of temporal isolation in determining patterns of gene flow, and hence population genetic structure and local adaptation, little is known about how changes in climate affect temporal isolation within populations.Here, we use flowering phenology and floral abundance data of 50 subalpine plant species over 44 years to test whether temporal isolation between habitat patches is affected by spring temperature. For each species and year, we analysed temporal separation in peak flowering and flowering overlap between habitat patches separated by 5–950 m.Across our study species, warmer springs were associated with more temporal differentiation in flowering peaks among habitat patches, and less flowering overlap, increasing potential for temporal isolation within populations.Synthesis. By reducing opportunities for mating among plants in nearby habitat patches, our results suggest that warmer springs may reduce opportunities for gene flow within populations, and, consequently, the capacity of plant populations to adapt to environmental changes.
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Panmixia in spiders ( Mecaphesa celer , Thomisidae) despite fragmented habitat at Craters of the Moon in Idaho
Abstract A fragmented landscape, which contains a patchwork of vegetated hospitable areas and a barren intervening matrix, may reduce gene flow in a population and over time result in an increase in population structure.We tested this prediction in crab spiders (Mecaphesa celer(Hentz, 1847)) inhabiting isolated habitat patches in the lava matrix of Craters of the Moon National Monument and Preserve, Idaho, USA.Using reduced‐representation genomic sequencing, we did not find evidence of population structure due to a reduction in gene flow among habitat patches.Instead, our results show strong evidence of panmixia likely due to abundant juvenile dispersal and possible connectivity to outer regions surrounding the lava flows despite the species' habitat specificity.
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- Award ID(s):
- 1751157
- PAR ID:
- 10373687
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecological Entomology
- Volume:
- 47
- Issue:
- 4
- ISSN:
- 0307-6946
- Format(s):
- Medium: X Size: p. 645-656
- Size(s):
- p. 645-656
- Sponsoring Org:
- National Science Foundation
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