Thrice out of Africa: ancient and recent expansions of the honey bee, Apis mellifera

We characterized Apis mellifera in both native and introduced ranges using 1136 single-nucleotide polymorphisms genotyped in 341 individuals. Our results indicate that A. mellifera originated in Africa and expanded into Eurasia at least twice, resulting in populations in eastern and western Europe that are geographically close but genetically distant. A third expansion in the New World has involved the near-replacement of previously introduced "European" honey bees by descendants of more recently introduced A. m. scutellata ("African" or "killer" bees). Our analyses of spatial transects and temporal series in the New World revealed differential replacement of alleles derived from eastern versus western Europe, with admixture evident in all individuals.     

Coxofemoral dislocations

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Sir,—The article by A. N. Bruere on “The Treatment of Coxofemoral Dislocations in the Dog” (N Z. vct. J., 9 : 70) is of great interest. I myself find that the easiest way to diagnose dislocation of this joint in the dog is to palpate the gap between the trochanter major and tuber ischii on each side and compare the two. This is done preferably in the standing position but may also be done in laterat recumbency.