Beetle horns are enlarged outgrowths of the head or thorax that are used as weapons in contests over access to mates. Horn development is typically confined to males (sexual dimorphism) and often only to the largest males (male dimorphism). Both types of dimorphism result from endocrine threshold mechanisms that coordinate cell proliferation near the end of the larval period. Here, we map the presence/absence of each type of dimorphism onto a recent phylogeny for the genus Onthophagus (Coleoptera: Scarabaeidae) to explore how horn development has changed over time. Our results provide empirical support for several recent predictions regarding the evolutionary lability of developmental thresholds, including uncoupled evolution of alternative phenotypes and repeated fixation of phenotypes. We also report striking evidence of a possible developmental constraint. We show that male dimorphism and sexual dimorphism map together on the phylogeny; whenever small males have horns, females also have horns (and vice versa). We raise the possibility that correlated evolution of these two phenomena results from a shared element in their endocrine regulatory mechanisms rather than a history of common selection pressures. These results illustrate the type of insight that can be gained only from the integration of developmental and evolutionary perspectives.

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Multiple-dose regimens of lansoprazole (> or =30 mg b.d. for 5 days) produce significantly increased intragastric pH and significantly longer duration of increased intragastric pH than does lansoprazole 30 mg administered once daily.

Objective To determine whether the use of serum insubetween these groups. The PSA level and age of the patients diCered significantly between the groups (both lin-like growth factor 1 (IGF-1) levels is more eBcient than serum prostate specific antigen (PSA) levels in P<0.001). There was no correlation between IGF-1 and PSA levels, and even when the age diCerence in predicting prostate cancer in patients undergoing prostatic biopsy.the groups was considered, there was still no significant relationship between IGF-1 levels and the inciPatients and methods The study included 94 consecutive patients who required transrectal ultrasonography dence of prostate cancer. In patients with a PSA level of 4-20 mg/L there was no statistically significant (TRUS)-guided biopsies of their prostate and who had blood samples taken before their biopsies. These diCerence in IGF-1 levels between the groups. Conclusion Serum IGF-1 as a tumour marker does not samples were then analysed for IGF-1 and PSA concentrations. Six prostatic biopsies were taken from each help to predict patients with prostate cancer. PSA level and even age were better predictors of the presence of patient; they were assessed and a diagnosis made of prostate cancer or no malignancy.prostate cancer than were serum IGF-1 levels.