In this chapter we review the formation and evolution of compact binaries with neutron star and/or black hole components (i.e. LMXBs, HMXBs, binary pulsars). After an introduction we discuss stellar evolution in binaries and the processes involved in the mass-transfer phases of close binaries (RLO, CE, ang.mom.loss) with radiative/convective hydrogen or helium donor stars. We also describe the effects of accretion, asymmetric SN and systems merging as a result of gravitational wave radiation.

RECENT advances in molecular genetics have had a great deal of influence on evolutionary theory, and in particular, the neutral mutation-random drift hypothesis of molecular evolution1,2 has stimulated much interest. The concept of neutral mutant substitution in the population by random genetic drift can be extended to include random fixation of very slightly deleterious mutations which have more chance of being selected against than of being selected for3,4. If this class of mutant substitution is important, we can predict that the evolution is rapid in small populations or at the time of speciation5. Here I shall organize the observed facts which indicate that this class is in fact important.

The nearly neutral theory contends that the interaction of drift and selection is important and occurs at various levels, including synonymous and nonsynonymous substitutions in protein coding regions and sequence turnover of regulatory elements. Recent progress of the theory is reviewed, and the interaction between drift and selection is suggested to differ at these different levels. Weak selective force on synonymous changes is stable, whereas its consequence on nonsynonymous changes depends on environmental factors. Selection on differentiation of regulatory elements is even more dependent on environmental factors than on amino acid changes. Of particular significance is the role of drift in the evolution of gene regulation that directly participates in morphological evolution. The range of near neutrality depends on the effective size of the population that is influenced by selected linked loci. In addition to the effective population size, molecular chaperones such as heat shock protein 90 have significant effects on the range of near neutrality.

Determining the extent of adaptive evolution at the genomic level is central to our understanding of molecular evolution. A suitable observation for this purpose would consist of polymorphic data on a large and unbiased collection of genes from two closely related species, each having a large and stable population. In this study, we sequenced 419 genes from 24 lines of Drosophila melanogaster and its close relatives. Together with data from Drosophila simulans, these data reveal the following. (i) Approximately 10% of the loci in regions of normal recombination are much less polymorphic at silent sites than expected, hinting at the action of selective sweeps. (ii) The level of polymorphism is negatively correlated with the rate of nonsynonymous divergence across loci. Thus, even under strict neutrality, the ratio of amino acid to silent nucleotide changes (A:S) between Drosophila species is expected to be 25-40% higher than the A:S ratio for polymorphism when data are pooled across the genome. (iii) The observed A/S ratio between species among the 419 loci is 28.9% higher than the (adjusted) neutral expectation. We estimate that nearly 30% of the amino acid substitutions between D. melanogaster and its close relatives were adaptive. (iv) This signature of adaptive evolution is observable only in regions of normal recombination. Hence, the low level of polymorphism observed in regions of reduced recombination may not be driven primarily by positive selection. Finally, we discuss the theories and data pertaining to the interpretation of adaptive evolution in genomic studies.

Although positive selection has been detected in many genes, its overall contribution to protein evolution is debatable. If the bulk of molecular evolution is neutral, then the ratio of amino-acid (A) to synonymous (S) polymorphism should, on average, equal that of divergence. A comparison of the A/S ratio of polymorphism in Drosophila melanogaster with that of divergence from Drosophila simulans shows that the A/S ratio of divergence is twice as high-a difference that is often attributed to positive selection. But an increase in selective constraint owing to an increase in effective population size could also explain this observation, and, if so, all genes should be affected similarly. Here we show that the difference between polymorphism and divergence is limited to only a fraction of the genes, which are also evolving more rapidly, and this implies that positive selection is responsible. A higher A/S ratio of divergence than of polymorphism is also observed in other species, which suggests a rate of adaptive evolution that is far higher than permitted by the neutral theory of molecular evolution.

The rate of amino acid substitutions in the evolution of homologous proteins is remarkably constant. Furthermore, estimated rates of amino acid substitutions based on comparisons of the alpha hemoglobin chains of various mammals with that of the carp are about the same as those based on comparisons of the carp alpha and mammalian beta or the alpha and beta chains in mammals. These uniformities are regarded as evidence for the hypothesis that a majority of amino acid substitutions that occurred in these proteins are the result of random fixation of selectively neutral or nearly neutral mutations. Two implications of this possibility are discussed: (a) Random gene frequency drift is playing an important role in determining the genetic structure of biological populations and (b) genes in "living fossils" may be expected to have undergone as many DNA base (and therefore amino acid) substitutions as corresponding genes (proteins) in more rapidly evolving species.

We explore the use of Evolution Strategies (ES), a class of black box optimization algorithms, as an alternative to popular MDP-based RL techniques such as Q-learning and Policy Gradients. Experiments on MuJoCo and Atari show that ES is a viable solution strategy that scales extremely well with the number of CPUs available: By using a novel communication strategy based on common random numbers, our ES implementation only needs to communicate scalars, making it possible to scale to over a thousand parallel workers. This allows us to solve 3D humanoid walking in 10 minutes and obtain competitive results on most Atari games after one hour of training. In addition, we highlight several advantages of ES as a black box optimization technique: it is invariant to action frequency and delayed rewards, tolerant of extremely long horizons, and does not need temporal discounting or value function approximation.

Proton pumping ATPases are found in all groups of present day organisms. The F-ATPases of eubacteria, mitochondria and chloroplasts also function as ATP synthases, i.e., they catalyze the final step that transforms the energy available from reduction/oxidation reactions (e.g., in photosynthesis) into ATP, the usual energy currency of modern cells. The primary structure of these ATPases/ATP synthases was found to be much more conserved between different groups of bacteria than other parts of the photosynthetic machinery, e.g., reaction center proteins and redox carrier complexes. These F-ATPases and the vacuolar type ATPase, which is found on many of the endomembranes of eukaryotic cells, were shown to be homologous to each other; i.e., these two groups of ATPases evolved from the same enzyme present in the common ancestor. (The term eubacteria is used here to denote the phylogenetic group containing all bacteria except the archaebacteria.) Sequences obtained for the plasmamembrane ATPase of various archaebacteria revealed that this ATPase is much more similar to the eukaryotic than to the eubacterial counterpart. The eukaryotic cell of higher organisms evolved from a symbiosis between eubacteria (that evolved into mitochondria and chloroplasts) and a host organism. Using the vacuolar type ATPase as a molecular marker for the cytoplasmic component of the eukaryotic cell reveals that this host organism was a close relative of the archaebacteria. A unique feature of the evolution of the ATPases is the presence of a non-catalytic subunit that is paralogous to the catalytic subunit, i.e., the two types of subunits evolved from a common ancestral gene. Since the gene duplication that gave rise to these two types of subunits had already occurred in the last common ancestor of all living organisms, this non-catalytic subunit can be used to root the tree of life by means of an outgroup; that is, the location of the last common ancestor of the major domains of living organisms (archaebacteria, eubacteria and eukaryotes) can be located in the tree of life without assuming constant or equal rates of change in the different branches. A correlation between structure and function of ATPases has been established for present day organisms. Implications resulting from this correlation for biochemical pathways, especially photosynthesis, that were operative in the last common ancestor and preceding life forms are discussed.

Summary. The evolutionary history of the wolf-like canids of the genus Canis has been heavily debated, especially regarding the number of distinct species and their relationships at the population and species level [1-6]. We assembled a dataset of 48 resequenced genomes spanning all members of the genus Canis except the black-backed and side-striped jackals, encompassing the global diversity of seven extant canid lineages. This includes eight new genomes, including the first resequenced Ethiopian wolf (Canis simensis), one dhole (Cuon alpinus), two East African hunting dogs (Lycaon pictus), two Eurasian golden jackals (Canis aureus), and two Middle Eastern gray wolves (Canis lupus). The relationships between the Ethiopian wolf, African golden wolf, and golden jackal were resolved. We highlight the role of interspecific hybridization in the evolution of this charismatic group. Specifically, we find gene flow between the ancestors of the dhole and African hunting dog and admixture between the gray wolf, coyote (Canis latrans), golden jackal, and African golden wolf. Additionally, we report gene flow from gray and Ethiopian wolves to the African golden wolf, suggesting that the African golden wolf originated through hybridization between these species. Finally, we hypothesize that coyotes and gray wolves carry genetic material derived from a "ghost" basal canid lineage.

Ground-penetrating radar (GPR) data for the Savannah River Site (SRS) in the Upper Coastal Plain of South Carolina, combined with geological, archaeological, and ecological data place new constraints on the evolution of Carolina Bays. Extant SRS bay morphology formed mainly during the Holocene and did not involve migration of bays across the landscape. Multiple periods of bay-rim accretion with intervening intervals of erosion may characterize the longer-term evolution of the bays. Bay evolution, however, did not involve significant modification of the Upland Unit underlying the region. During fluctuating, but generally open water conditions, breaking waves along bay shorelines eroded and transported sediment which was subsequently exposed for deflation during periods of low water. Deflation and transport of sand into standing vegetation along the margin of the bay depression created a rim in the form of a parabolic dune lacking obvious internal stratification. Simultaneously, infilling occurred by shoreline erosion and transport from adjacent elevated surfaces. This, coupled with growth of emergent vegetation, resulted in decreased hydroperiod, wave energy, shoreline modification, and rim accretion. Transport of some rim sediments back into the bays via alluvial and colluvial activity created wedges of infilling sediment during waning stages of evolution. The apparent contradiction of bay orientation with respect to prevailing winds might reflect seasonal changes in water level and wind direction: southwesterly winds during spring high water causes NW-SE elongation of the bays, whereas northwesterly winds during lower water in the fall and winter account for nearshore deflation and rim accretion along the east-southeastern bay margins.

This paper intends to give a broad overview of the present knowledge about neutron star magnetic fields, their origin and evolution. An up-to-date overview of the rich phenomenology (encompassing ``classical'' and millisecond radio pulsars, X-ray binaries, ``magnetars'', and ``thermal emitters'') suggests that magnetic fields on neutron stars span at least the range $10^{8-15}$ G, corresponding to a range of magnetic fluxes similar to that found in white dwarfs and upper main sequence stars. The limitations of the observational determinations of the field strength and evidence for its evolution are discussed. Speculative ideas about the possible main-sequence origin of the field (``magnetic strip-tease'') are presented. Attention is also given to physical processes potentially leading to magnetic field evolution.