ABSTRACT
To investigate the origins and stages of vertebrate adaptive radiation, we reconstructed the spatial and temporal histories of adaptive alleles underlying major phenotypic axes of diversification from the genomes of 202 Caribbean pupfishes. On a single Bahamian island, ancient standing variation from disjunct geographic sources was reassembled into new combinations under strong directional selection for adaptation to the novel trophic niches of scale-eating and molluscivory. We found evidence for two longstanding hypotheses of adaptive radiation: hybrid swarm origins and temporal stages of adaptation. Using a combination of population genomics, transcriptomics, and genome-wide association mapping, we demonstrate that this microendemic adaptive radiation of novel trophic specialists on San Salvador Island, Bahamas experienced twice as much adaptive introgression as generalist populations on neighboring islands and that adaptive divergence occurred in stages. First, standing regulatory variation in genes associated with feeding behavior (prlh, cfap20, and rmi1) were swept to fixation by selection, then standing regulatory variation in genes associated with craniofacial and muscular development (itga5, ext1, cyp26b1, and galr2) and finally the only de novo nonsynonymous substitution in an osteogenic transcription factor and oncogene (twist1) swept to fixation most recently. Our results demonstrate how ancient alleles maintained in distinct environmental refugia can be assembled into new adaptive combinations and provide a framework for reconstructing the spatiotemporal landscape of adaptation and speciation.
Subject(s)
Adaptation, Physiological/genetics , Genetic Speciation , Killifishes/genetics , Phylogeny , Spatio-Temporal Analysis , Vertebrates/genetics , Animals , Bahamas , Caribbean Region , Fish Proteins/genetics , Gene Expression Profiling/methods , Genome-Wide Association Study/methods , Genomics/methods , Genotype , Geography , Killifishes/anatomy & histology , Killifishes/classification , Polymorphism, Single Nucleotide , Vertebrates/anatomy & histology , Vertebrates/classificationABSTRACT
PURPOSE/OBJECTIVES: To objectively assess physical activity (PA) levels in a cohort of Spanish cancer survivors. DESIGN: Descriptive, cross-sectional. SETTING: The Hospital Universitario de Fuenlabrada and two healthcare centers in Madrid, Spain. SAMPLE: 204 cancer survivors and 115 adults with no history of cancer. METHODS: Participants wore a triaxial accelerometer for seven or more consecutive days to assess PA levels. Body mass index (BMI), indirect indicators of adiposity (waist circumference, waist-to-hip ratio), and cardiorespiratory fitness also were determined. MAIN RESEARCH VARIABLES: Light, moderate, vigorous, and total PA (sum of the former). FINDINGS: Most (94%) of the cancer survivors met international recommendations for moderate PA, but very few (3%) fulfilled those (75 minutes or more per week) for vigorous PA. Except for lower total (minute per day, p=0.048) and vigorous PA levels (p<0.001 for both minute per day and minute per week) recorded in the cancer survivors group, no between-group differences were detected (p>0.05). A high percentage of the survivors (33%) were obese (BMI greater than 30 kg/m2), and many also showed poor cardiorespiratory fitness (45% were below the 8 metabolic equivalent threshold). CONCLUSIONS: Although cancer survivors overall met international PA recommendations for a healthy lifestyle, their BMI and cardiorespiratory profiles were not within the healthy range. IMPLICATIONS FOR NURSING: Cancer survivors need to be informed about healthy lifestyle habits and should be regularly monitored.
