Publications by authors named "G L Eichhorn"

Intermittent breeding is an important tactic in long-lived species that trade off survival and reproduction to maximize lifetime reproductive success. When breeding conditions are unfavourable, individuals are expected to skip reproduction to ensure their own survival. Breeding propensity (i.

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Performing migratory journeys comes with energetic costs, which have to be compensated within the annual cycle. An assessment of how and when such compensation occurs is ideally done by comparing full annual cycles of migratory and non-migratory individuals of the same species, which is rarely achieved. We studied free-living migratory and resident barnacle geese belonging to the same flyway (metapopulation), and investigated when differences in foraging activity occur, and when foraging extends beyond available daylight, indicating a diurnal foraging constraint in these usually diurnal animals.

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Background: The effects of Anabolic Androgenic Steroids (AAS) are largely illustrated through Androgen Receptor induced gene transcription, yet RNA-Seq has yet to be conducted on human whole blood and skeletal muscle. Investigating the transcriptional signature of AAS in blood may aid AAS detection and in muscle further understanding of AAS induced hypertrophy.

Methods: Males aged 20-42 were recruited and sampled once: sedentary controls (C), resistance trained lifters (RT) and resistance trained current AAS users (RT-AS) who ceased exposure ≤ 2 or ≥ 10 weeks prior to sampling.

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The physiological performance of organisms depends on their environmental context, resulting in performance-response curves along environmental gradients. Parasite performance-response curves are generally expected to be broader than those of their hosts due to shorter generation times and hence faster adaptation. However, certain environmental conditions may limit parasite performance more than that of the host, thereby providing an environmental refuge from disease.

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Article Synopsis
  • Good genes theories suggest that polygamy helps remove harmful genetic alleles more effectively due to the alignment of sexual and natural selection, unlike runaway selection theories which predict less efficiency in purifying selection for polygamous species.
  • Analysis of data from 150 bird genomes indicates that polygamous birds have significantly fewer harmful genetic variations than monogamous ones, supporting the "good genes" perspective (p = .0005), regardless of population size.
  • While polygamy didn't affect overall genetic diversity, there was a marginally significant impact on genetic variation in female polyandrous species (p = .045); additionally, smaller body size and larger geographic ranges correlated with better purifying selection and greater genetic diversity
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