Here we report the genome sequence of the honeybee Apis mellifera, a key model for social behaviour and essential to global ecology through pollination. Compared with other sequenced insect genomes, the A. mellifera genome has high A+T and CpG contents, lacks major transposon families, evolves more slowly, and is more similar to vertebrates for circadian rhythm, RNA interference and DNA methylation genes, among others. Furthermore, A. mellifera has fewer genes for innate immunity, detoxification enzymes, cuticle-forming proteins and gustatory receptors, more genes for odorant receptors, and novel genes for nectar and pollen utilization, consistent with its ecology and social organization. Compared to Drosophila, genes in early developmental pathways differ in Apis, whereas similarities exist for functions that differ markedly, such as sex determination, brain function and behaviour. Population genetics suggests a novel African origin for the species A. mellifera and insights into whether Africanized bees spread throughout the New World via hybridization or displacement.

The nonlinear optical constant of AgGaS2 was determined to be d 36 (AgGaS2)=(0.84 ±0.1) ×d 36 (AgGaSe2) =(34.8 ±4) pm/V from the direct comparison of the second-harmonic generation conversion (SHG) efficiencies of a CO2 laser at 9.2714 µm observed in AgGaSe2 under the identical experimental conditions. The phase-matching conditions for type-1 SHG in both AgGaS2 and AgGaSe2 are presented together with the damage thresholds at 9.2714 µm and 2.097 µm.

The current insect genome sequencing projects provide an opportunity to extend studies of the evolution of developmental genes and pathways in insects. In this paper we examine the conservation and divergence of genes and developmental processes between Drosophila and the honey bee; two holometabolous insects whose lineages separated ∼300 million years ago, by comparing the presence or absence of 308 Drosophila developmental genes in the honey bee. Through examination of the presence or absence of genes involved in conserved pathways (cell signaling, axis formation, segmentation and homeobox transcription factors), we find that the vast majority of genes are conserved. Some genes involved in these processes are, however, missing in the honey bee. We have also examined the orthology of Drosophila genes involved in processes that differ between the honey bee and Drosophila. Many of these genes are preserved in the honey bee despite the process in which they act in Drosophila being different or absent in the honey bee. Many of the missing genes in both situations appear to have arisen recently in the Drosophila lineage, have single known functions in Drosophila, and act early in developmental pathways, while those that are preserved have pleiotropic functions. An evolutionary interpretation of these data is that either genes with multiple functions in a common ancestor are more likely to be preserved in both insect lineages, or genes that are preserved throughout evolution are more likely to co-opt additional functions.

KTP has been found to be phase matchable for type-2 second-harmonic generation of the third harmonics of the CO2 laser wavelengths at 9.2714 and 9.5525 microm at 20.0 degrees C. The resulting angle and temperature-tuning data combined with the literature values of the Nd:YAG laser-pumped optical parametric oscillator were used to improve the Sellmeier equations and the thermo-optic dispersion formula that reproduce well the temperature-tuned 90 degree phase-matching conditions of the flux-grown crystals. Applications to quasi phase matching are presented.

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