Publications by authors named "T R Garland"
Artificial selection yielded four replicate high runner (HR) lines of mice that reached apparent selection limits (~ threefold increase in wheel revolutions per day vs. four control lines), despite maintenance of additive genetic variance. After 68 generations, we used animal models to test for changes in additive-genetic variances and covariance of the two measured components (average speed and duration) of running distance.
View Article and Find Full Text PDFMaternal exercise opportunity before, during, and after pregnancy alters maternal care behavior and offspring development and survival, but has few effects on offspring physical activity or body composition.
Physiol Behav
November 2024
Article Synopsis
- Early-life experiences, particularly parental behaviors during critical development periods, can have significant long-term effects on offspring traits in mammals.
- In an experiment with mice selectively bred for high running behavior, researchers investigated how maternal exercise affected maternal care and offspring physical activity and body composition.
- Results showed that HR mice (high runners) exhibited less maternal care when exercising compared to non-selected CON dams, with implications for offspring health and development.
Article Synopsis
- High mechanical loading induces temporary disruptions in cell membranes (PMD) that initiate a process called mechanotransduction, which is essential for bone adaptation.
- The study hypothesized that disrupting a protein called β2-spectrin (Sptbn1), which supports cell structure, would increase membrane fragility, leading to altered responses in osteocytes (bone cells) under mechanical stress.
- Results showed that disrupting Sptbn1 led to more PMD formation and slower repair rates in cells, impaired cell survival, and reduced bone thickening in response to mechanical loading, highlighting Sptbn1's crucial role in bone adaptation and cell response to stress.
AbstractMuscle-tendon unit (MTU) morphology and physiology are likely major determinants of locomotor performance and therefore Darwinian fitness. However, the relationships between underlying traits, performance, and fitness are complicated by phenomena such as coadaptation, multiple solutions, and trade-offs. Here, we leverage a long-running artificial selection experiment in which mice have been bred for high levels of voluntary running to explore MTU adaptation, as well as the role of coadaptation, multiple solutions, and trade-offs, in the evolution of endurance running.
View Article and Find Full Text PDFSelection experiments play an increasingly important role in comparative and evolutionary physiology. However, selection experiments can be limited by relatively low statistical power, in part because replicate line is the experimental unit for analyses of direct or correlated responses (rather than number of individuals measured). One way to increase the ability to detect correlated responses is through a meta-analysis of studies for a given trait across multiple generations.
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