Rapid independent trait evolution despite a strong pleiotropic genetic correlation.

Genetic correlations are the most commonly studied of all potential constraints on adaptive evolution. We present a comprehensive test of constraints caused by genetic correlation, comparing empirical results to predictions from theory. The additive genetic correlation between the filament and the corolla tube in wild radish flowers is very high in magnitude, is estimated with good precision (0.

Getting to the heart of rectal bleeding: subacute bacterial endocarditis presenting as anaemia and a GI bleed.

In this case report, the authors demonstrate a case of subacute bacterial endocarditis presenting with anaemia. It is the first of its kind to describe a delay in diagnosis due to an initial patient investigation for a bleed rather than a cardiac evaluation. Astute clinicians need to be aware of the causes of anaemia in patients with endocarditis and consider that in Streptococcus bovis (S bovis) infection can be related to gastrointestinal polyps or malignancy resulting in bleeding.

Bone outcomes and technical measurement issues of bone health among children and adolescents: considerations for nutrition and physical activity intervention trials.

Weight-bearing physical activity and calcium intake are two important behavioral influences for bone health. Physical-activity and calcium-intake intervention trials with youth have been implemented to evaluate their efficacy and effectiveness to decrease the risk for subsequent osteoporosis and fractures. Technical aspects of bone measurement have not been routinely reported in published trials of youth, even though they can have an impact on study findings and interpretation.

Expression of additive genetic variances and covariances for wild radish floral traits: comparison between field and greenhouse environments.

Measurements of the genetic variation and covariation underlying quantitative traits are crucial to our understanding of current evolutionary change and the mechanisms causing this evolution. This fact has spurred a large number of studies estimating heritabilities and genetic correlations in a variety of organisms. Most of these studies have been done in laboratory or greenhouse settings, but it is not well known how accurately these measurements estimate genetic variance and covariance expressed in the field.

Patterns and mechanisms of selection on a family-diagnostic trait: evidence from experimental manipulation and lifetime fitness selection gradients.

Plant traits that show little variation across higher taxa are often used as diagnostic traits, but the reason for the stasis of such traits remains unclear. Wild radish, Raphanus raphanistrum, exhibits tetradynamous stamens (four long and two short, producing a dimorphism in anther height within each flower), as do the vast majority of the more than 3,000 species in the Brassicaceae. Here we examine the hypothesis that selection maintains the stasis of dimorphic anther height by investigating the effects of this trait on pollen removal, seed siring success, and seed set in R.