Undesirable evolutionary consequences of trophy hunting

Phenotype-based selective harvests, including trophy hunting, can have important implications for sustainable wildlife management if they target heritable traits. Here we show that in an evolutionary response to sport hunting of bighorn trophy rams (Ovis canadensis) body weight and horn size have declined significantly over time. We used quantitative genetic analyses, based on a partly genetically reconstructed pedigree from a 30-year study of a wild population in which trophy hunting targeted rams with rapidly growing horns, to explore the evolutionary response to hunter selection on ram weight and horn size. Both traits were highly heritable, and trophy-harvested rams were of significantly higher genetic 'breeding value' for weight and horn size than rams that were not harvested. Rams of high breeding value were also shot at an early age, and thus did not achieve high reproductive success. Declines in mean breeding values for weight and horn size therefore occurred in response to unrestricted trophy hunting, resulting in the production of smaller-horned, lighter rams, and fewer trophies.     

The effect of lithium carbonate on the granulocyte phagocytic index

Summary Preincubation in lithium carbonate of granulocytes from normal human male volunteer subjects did not alter the ability of these cells to perform properly the ingestion phase of phagocytosis in vitro.The voluntary fully informed consent of the subjects used in this research was obtained as required by AFR No. 169-8.Acknowledgements. Mr.A. J. Rahe of the Biometrics Division, USAF School of Aerospace Medicine, Brooks Air Force Base, TX. provided the statistical analysis. The LC used in this study was provided through the courtesy of Pfizer, Inc., Brooklyn, N.Y., USA.