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Climate change threatens the survival of coral reefs on a global scale, primarily through mass bleaching and mortality as a result of marine heatwaves. While these short-term effects are clear, predicting the fate of coral reefs over the coming century is a major challenge. One way to understand the longer-term effect of rapid climate change is to examine the response of coral populations to past climate shifts. Coastal and shallow-water marine ecosystems such as coral reefs have been reshaped many times by sea-level changes during the Pleistocene, yet few studies have directly linked this with its consequences on population demographics, dispersal, and adaptation. Here we use powerful analytical techniques, afforded by haplotype-phased whole-genomes, to establish such links for the reef-building coral, Acropora digitifera. We show that three genetically distinct populations are present in northwestern Australia, and that their rapid divergence since the last glacial maximum (LGM) can be explained by a combination of founder-effects and restricted gene flow. Signatures of selective sweeps, too strong to be explained by demographic history, are present in all three populations and overlap with genes that show different patterns of functional enrichment between inshore and offshore habitats. In contrast to rapid divergence in the host, we find that photosymbiont communities are largely undifferentiated between corals from all three locations, spanning almost 1000 km, indicating that selection on host genes, and not acquisition of novel symbionts, has been the primary driver of adaptation for this species in northwestern Australia., source:https://academic.oup.com/mbe/article/39/10/msac201/6711762

Climate change threatens the survival of coral reefs on a global scale, primarily through mass bleaching and mortality as a result of marine heatwaves. While these short-term effects are clear, predicting the fate of coral reefs over the coming century is a major challenge. One way to understand the longer-term effect of rapid climate change is to examine the response of coral populations to past climate shifts. Coastal and shallow-water marine ecosystems such as coral reefs have been reshaped many times by sea-level changes during the Pleistocene, yet few studies have directly linked this with its consequences on population demographics, dispersal, and adaptation. Here we use powerful analytical techniques, afforded by haplotype-phased whole-genomes, to establish such links for the reef-building coral, Acropora digitifera. We show that three genetically distinct populations are present in northwestern Australia, and that their rapid divergence since the last glacial maximum (LGM) can be explained by a combination of founder-effects and restricted gene flow. Signatures of selective sweeps, too strong to be explained by demographic history, are present in all three populations and overlap with genes that show different patterns of functional enrichment between inshore and offshore habitats. In contrast to rapid divergence in the host, we find that photosymbiont communities are largely undifferentiated between corals from all three locations, spanning almost 1000 km, indicating that selection on host genes, and not acquisition of novel symbionts, has been the primary driver of adaptation for this species in northwestern Australia., source:https://academic.oup.com/mbe/article/39/10/msac201/6711762

The application of environmental DNA technologies is a promising new approach to rapidly audit biodiversity across large-scale, remote regions. Here, we examine the efficacy of a dual-assay eDNA metabarcoding approach for sessile benthic bioassessments in the turbid waters of the Lalang-garram marine parks, Kimberley, north-western Australia. We ask three principal questions: (1) “Is the eDNA released by sessile benthic taxa (i.e., hard and soft corals, sponges and tunicates) locally detectable?”, (2) “What level of taxonomic resolution is afforded by eDNA metabarcoding using the ITS2 region?”, and (3) “How well does eDNA metabarcoding compare to conventional benthic survey techniques?”. We report that a dual-assay eDNA metabarcoding approach can detect approximately 70% of the local benthic taxa (i.e., at a species, genus level). It is, however, not as effective at the individual/population level, detecting only approximately 40% of unique amplicon sequence variant (ASV) signals released by an array of individual benthic organisms at the surveyed locations. In examining the efficacy and resolution of the applied ITS2 metabarcoding markers for bioassessments, we report large gaps in the variety of publicly available benthic ITS2 reference sequence data, limiting our ability to provide robust taxonomic assignments. These findings highlight the need to extend ITS2 databases for greater regional representation. Until this is adequately addressed, we recommend that investigating taxonomic assignments to a genus level is the most robust approach for benthic monitoring using eDNA. Lastly, we found eDNA metabarcoding and conventional belt transect surveys each detected numerous unique hard coral genera, indicating that a combined approach provides the most effective way to audit benthic biodiversity. This point notwithstanding, eDNA metabarcoding had the power to distinguish similar diversity trends between sites to that determined by the belt transect methodology, validat

The application of environmental DNA technologies is a promising new approach to rapidly audit biodiversity across large-scale, remote regions. Here, we examine the efficacy of a dual-assay eDNA metabarcoding approach for sessile benthic bioassessments in the turbid waters of the Lalang-garram marine parks, Kimberley, north-western Australia. We ask three principal questions: (1) “Is the eDNA released by sessile benthic taxa (i.e., hard and soft corals, sponges and tunicates) locally detectable?”, (2) “What level of taxonomic resolution is afforded by eDNA metabarcoding using the ITS2 region?”, and (3) “How well does eDNA metabarcoding compare to conventional benthic survey techniques?”. We report that a dual-assay eDNA metabarcoding approach can detect approximately 70% of the local benthic taxa (i.e., at a species, genus level). It is, however, not as effective at the individual/population level, detecting only approximately 40% of unique amplicon sequence variant (ASV) signals released by an array of individual benthic organisms at the surveyed locations. In examining the efficacy and resolution of the applied ITS2 metabarcoding markers for bioassessments, we report large gaps in the variety of publicly available benthic ITS2 reference sequence data, limiting our ability to provide robust taxonomic assignments. These findings highlight the need to extend ITS2 databases for greater regional representation. Until this is adequately addressed, we recommend that investigating taxonomic assignments to a genus level is the most robust approach for benthic monitoring using eDNA. Lastly, we found eDNA metabarcoding and conventional belt transect surveys each detected numerous unique hard coral genera, indicating that a combined approach provides the most effective way to audit benthic biodiversity. This point notwithstanding, eDNA metabarcoding had the power to distinguish similar diversity trends between sites to that determined by the belt transect methodology, validat

Unmet demand for outdoor recreation in the Mogollon Rim study area; Effects of selected management alternatives on recreational use in the Mogollon Rim area

Recreational and Scientific Activity in Cave Creek Canyon, Chiricahua Mountains, Arizona, 1978-1979

Impact of Pandora Moth Defoliation on Scenic Quality and Recreation Value of Forested Area