Publications by authors named "Alex Landy"

The role of phenotypic plasticity in adaptive evolution has been debated for decades. This is because the strength of natural selection is dependent on the direction and magnitude of phenotypic responses to environmental signals. Therefore, the connection between plasticity and adaptation will depend on the patterns of plasticity harbored by ancestral populations before a change in the environment.

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An important step in diagnosing local adaptation is the demonstration that phenotypic variation among populations is at least in part genetically based. To do this, many methods experimentally minimize the environmental effect on the phenotype to elucidate the genetic effect. Minimizing the environmental effect often includes reducing possible environmental maternal effects.

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Studies of the adaptive significance of variation among conspecific populations often focus on a single ecological factor. However, habitats rarely differ in only a single ecological factor, creating a challenge for identifying the relative importance of the various ecological factors that might be maintaining local adaptation. Here we investigate the ecological factors associated with male body shape variation among nine populations of the poeciliid fish, Heterandria formosa, from three distinct habitats and combine those results with a laboratory study of three of those populations to assess the contributions of genetic and environmental influences to shape variation.

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Background: Dyskinesias associated with involuntary movements and painful muscle contractions are a common and severe complication of standard levodopa (L-DOPA, L-3,4-dihydroxyphenylalanine) therapy for Parkinson's disease. Pathologic neuroplasticity leading to hyper-responsive dopamine receptor signaling in the sensorimotor striatum is thought to underlie this currently untreatable condition.

Methodology/principal Findings: Quantitative real-time polymerase chain reaction (PCR) was employed to evaluate the molecular changes associated with L-DOPA-induced dyskinesias in Parkinson's disease.

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