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Summary We study here the effect of using genome-wide marker data versus genealogical data in population management for the maintenance of diversity in conservation schemes using optimal contributions. We re-examine the benefits of using molecular data for different population and genome sizes and compare different management strategies according to the group of individuals where we take decisions (parents or offspring). We also study the consequences of using estimated genealogical coancestries calculated from molecular information. Using genome-wide marker data performed usually better than using genealogical data or estimated genealogical coancestry to maintain expected and observed heterozygosity. Furthermore, when we could take decisions acting on the offspring, a larger heterozygosity was maintained than when we based our decisions on the potential parents.

An experiment with mice was designed to test the relative efficiency of three selection methods that help to minimize the rate of inbreeding during selection. A common house mice (Mus musculus) population was selected for 17 generations to increase the weight gain between 21 and 42 days. The population was split at random into three lines A, B and C where three selection methods were applied: individual selection and random mating, weighted selection with random mating and individual selection with minimum coancestry mating, respectively. There were three replicates for each line. Cumulated selection response was similar in the three lines, but there were differences in the level of inbreeding attained (in percentage): 31.24 (method A), 24.72 (method B) and 27.88 (method C). As consequence, lines B and C (weighted selection and minimum coancestry) showed a lower value of deterioration of fitness traits (the intrauterine mortality and the mortality at birth) than line A (random mating).

Four major problems can affect the efficiency of methods developed to estimate relatedness between individuals from information of molecular markers: (i) some of them are dependent on the knowledge of the true allelic frequencies in the base population; (ii) they assume that all loci are unlinked and in Hardy–Weinberg and linkage equilibrium; (iii) pairwise methods can lead to incongruous assignations because they take into account only two individuals at a time; (iv) most are usually constructed for particular structured populations (only consider a few relationship classes, e.g. full-sibs vs. unrelated). We have developed a new approach to estimate relatedness that is free from the above limitations. The method uses a ‘blind search algorithm’ (actually simulated annealing ) to find the genealogy that yield a co-ancestry matrix with the highest correlation with the molecular co-ancestry matrix calculated using the markers. Thus (i and ii) it makes no direct assumptions about allelic frequencies or Hardy–Weinberg and linkage equilibrium; (iii) it always provide congruent relationships, as it considers all individuals at a time; (iv) degrees of relatedness can be as complex as desired just increasing the ‘depth’ (i.e. number of generations) of the proposed genealogies. Computer simulations have shown that the accuracy and robustness against genotyping errors of this new approach is comparable to that of other proposed methods in those particular situations they were developed for, but it is more flexible and can cope with more complex situations.

A Correction to this article has been published in Software Process: Improvement and Practice 2005; 10(3):355 In this article, we present an integrated framework for software process improvement according to the Capability Maturity Model (CMM). The framework is double-integrated. First, it is based on the systematic integration of dynamic modules to build dynamic models that model and simulate each maturity level proposed in the reference model. As a consequence, a hierarchical set of dynamic models is developed following the same hierarchy of levels suggested in the CMM. Second, the dynamic models of the framework are integrated with different static techniques commonly used in planning, control, and process evaluation. The paper describes the reasons found to follow this approach, the integration process of models and techniques, the implementation of the framework, and shows an example of how it can be used in a software process improvement concerning the cost of software quality. Copyright © 2004 John Wiley & Sons, Ltd.

In the context of the Multiparty Interaction Model, fairness is used to insure that an interaction that is enabled sufficiently often in a concurrent program will eventually be selected for execution. Unfortunately, this notion does not take conspiracies into account, i.e. situations in which an interaction never becomes enabled because of an unfortunate interleaving of independent actions; furthermore, eventual execution is usually too weak for practical purposes since this concept can only be used in the context of infinite executions. In this article, we present a new fairness notion, k-conspiracy-free fairness, that improves on others because it takes finite executions into account, alleviates conspiracies that are not inherent to a program, and k may be set a priori to control its goodness to address the above-mentioned problems. Ministerio de Ciencia y Tecnología TIC-2000-1106-C02-01 Ministerio de Ciencia y Tecnología FIT-150100-2001-78 Ministerio de Ciencia y Tecnología TAMANSI PCB-02-001

The effect of population bottlenecks on the components of the genetic variance generated by two neutral independent epistatic loci has been studied theoretically (VA, additive; VD, dominant; VAA, additive x additive; VAD, additive x dominant; VDD; dominant x dominant components of variance). Nonoverdominance and overdominance models were considered, covering all possible types of marginal gene action at the single locus level. The variance components in an infinitely large panmictic population (ancestral components) were compared with their expected values at equilibrium, after t consecutive bottlenecks of equal size N (derived components). Formulae were obtained in terms of allele frequencies and effects at each locus and the corresponding epistatic value. An excess of VA after bottlenecks can be assigned to two sources: (1) the spatiotemporal changes in the marginal average effects of gene substitution alpha(i), which are equal to zero only for additive gene action within and between loci; and (2) the covariance between alpha2(i) and the heterozygosity at the loci involved, which is generated by dominance, with or without epistasis. Numerical examples were analyzed, indicating that an increase in VA after bottlenecks will only occur if its ancestral value is minimal or very small. For the nonoverdominance model with weak reinforcing epistasis, that increase has been detected only for extreme frequencies of the negative allele at one or both loci. With strong epistasis, however, this result can be extended to a broad range of intermediate frequencies. With no epistasis, the same qualitative results were found, indicating that dominance can be considered as the primary cause of an increase in VA following bottlenecks. In parallel, the derived total nonadditive variance exceeded its ancestral value (V(NA) = V(D) + V(AA) + V(AD) + V(DD)) for a range of combinations of allele frequencies covering those for an excess of VA and for very large frequencies of the negative allele at both loci. For the overdominance model, an increase in V(A) and V(NA) was respectively observed for equilibrium (intermediate) frequencies at one or both loci or for extreme frequencies at both loci. For all models, the magnitude of the change of V(A) and V(NA) was inversely related to N and t. At low levels of inbreeding, the between-line variance was not affected by the type of gene action. For the models considered, the results indicate that it is unlikely that the rate of evolution may be accelerated after population bottlenecks, in spite of occasional increments of the derived V(A) over its ancestral value.

A method for obtaining coordinated motion plans of robot manipulators is presented. A decoupled planning approach has been used; that is, the problem has been decomposed into two subproblems: path planning, where a collision-free path is found for each robot independently only considering fixed obstacles, and trajectory planning, where the paths are timed and synchronized to avoid collisions with other robots. This article focuses on the second problem. The proposed plan can easily be implemented by programs written in most industrial robot programming languages. The generated programs minimize the total motion time of the robots along their paths. The method does not require accurate dynamic models of the robots and uses an evolutionary algorithm followed by a local search which produces near optimal solutions with a relatively small computational cost. © 2001 John Wiley & Sons, Inc.

In a conservation programme with genealogical records it is possible to estimate the amount of variability of the founder population from a measure of the similarity among the individuals in the current population based on microsatellite markers. Here we compare three available methods and we shown that the one based on the molecular coancestry coefficient should be preferred.

Summary Buffaloes are generally raised in Brazil without milk-recording programs, and thus without genetic evaluations of any of their traits. This study evaluated the economic impacts of three different selection strategies on buffalo populations and the evolution of genetic trends, genetic variances and inbreeding coefficients resulting from each of them. The selection strategies used were as follows: (i) random selection; (ii) phenotypic selection; and (iii) progeny testing (PT). As the numbers of herds enrolled in milk-recording programs increased, phenotypic selection and PT strategies increased both monetary benefits and genetic trends. The extra costs of implementing milk recording (MR) and PT procedures were exceeded by the income resulting from better buffalo performance. Progeny testing is known to result in beneficial genetic trends and the use of artificial insemination promoted better distributions of genetic material into herds that were not enrolled in milk-recording programs. Phenotypic selection and PT increased mean milk production - a key factor in profitability. Inbreeding levels remained stable with phenotypic selection, even as the numbers of MR herds increased. Increases in the numbers of sires that were evaluated reduced the mean inbreeding coefficient in PT. Increasing the number of herds enrolled in milk-recording programs resulted in increased numbers of sires needed for PT, but this did not increase the inbreeding coefficient. In summary, phenotypic selection and PT strategies appear to be economically viable for buffalo husbandry in south-eastern Brazil under current (2007–2008) economic conditions and should be encouraged.

Cultural transmission in our species is a cumulative inheritance system that leads to a cultural evolution process with a great adaptive value. Our genes have promoted a social learning system very effective for the transmission of learned behaviours. The ability to accumulate knowledge based on an efficient transmission process is what distinguishes human culture from other kinds of social learning present in nonhuman primates. Human behaviour is a product of two different and interacting processes: genetic evolution and cultural evolution. Much variation in human behaviour cannot be understood without accounting for beliefs, values and other socially acquired determinants of behaviour. Thus, culture is crucial for understanding human behaviour and coevolves with biology. On the one hand, the psychobiological capacities guiding cultural processes are the product of evolution. On the other hand, culture modifies the environment in which we live and therefore determine future action of natural selection. Key Concepts: Human culture is a system of inheritance, in which people acquire skills, techniques, beliefs, values, norms, desires and so on, by imitation and teaching. Cultural transmission arises from genetically evolved psychological adaptations for acquiring cultural traits from other individuals by observation and inference. Cultural transmission differs from nonhuman primate social learning in that it is cumulative. Cumulative cultural transmission led to a cultural evolution process with a great adaptive value. Evolved psychobiological mechanisms guide the preference among different cultural variants. Culture created social environments, in which specific adaptations were selected for by natural selection. Keywords: culture; cultural evolution; dual inheritance theory; sociobiology; meme; evolutionary psychology; assessor hominids; social learning

Livestock breeds are recognized as important components of world biodiversity. The Iberian pig is a swine breed well adapted to the Mediterranean forest ecosystem and provides cured products of high quality. The ancient population of Iberian pigs ( Sus scrofa meridionalis) was differentiated in several local types, the black hairless pigs representing the fattest genetic type. The conservation program of the Guadyerbas strain has maintained this germplasm isolated since 1945 as a closed population in an experimental herd. The complete pedigree, with 1000 breeding animals descending from 24 founders, has been used to measure along the successive cohorts of breeding animals the effective number of founders, effective number of nonfounders, founder genome equivalents, and expected number of founders' surviving alleles. For the last cohort, the values were 10.34, 1.42, 1.25, and 4.06, respectively. The evolution of inbreeding and coancestry and its components attributable to each founder were also studied. The rate of increase in inbreeding and coancestry was 2.21% per cohort, or 0.906% per year. Finally, the effect of family structure and mating tactics on the evolution of coancestry was also analyzed. The greatest rates of coancestry per cohort were attributable to unbalanced family sizes, and the use of minimum coancestry matings effectively delayed the increase in inbreeding.Las razas de ganado son consideradas como un componente importante de la biodiversidad mundial. El cerdo Ibérico es una raza de cerdos bien adaptada al ecosistema forestal del Mediterráneo y provee productos encurtidos de alta calidad. La población ancestral del cerdo Ibérico ( Sus scrofa meridionalis) era diferenciada en diversos tipos locales, siendo los cerdos lampiños negros los representantes del tipo genético más gordo. El programa de conservación de la variedad Guadyerbas ha mantenido su germoplasma aislado desde 1945 como una población cerrada en una manada experimental. El pedigrí completo con 1000 animales reproductores descendientes de 24 fundadores ha sido usado para medir a lo largo de cohortes sucesivas de animales reproductores el número efectivo de fundadores, el número efectivo de no-fundadores, el genoma fundador equivalente y el número esperado de alelos fundadores sobrevivientes. Para la última cohorte, los valores fueron 10.34, 1.42, 1.25 y 4.06, respectivamente. También estudiamos la evolución de endogamia y codescendencia y sus componentes debidos a cada fundador. La tasa de incremento en endogamia y codescendencia fue del 2.21% por cohorte, o el equivalente a 0.906 % por año. Finalmente, analizamos el efecto de la estructura familiar y las tácticas de apareamiento en la evolución de la codescendencia. Las tasas más grandes de codescendencia por cohorte fueron atribuibles a tamaños familiares desbalanceados y al uso mínimo de apareamientos de codescendientes, retardando efectivamente el incremento de la endogamia.

Introduction Selection on the best estimate of the breeding value of individuals should, in large populations, provide the maximal response in breeding value. However, many breeders deal with the selection of small numbers of animals from relatively small populations and therefore there is a trend for inbreeding to rise because of genetic drift. Moreover, as the evaluation of candidates is traditionally based on methodologies including information from relatives [selection indices, best linear unbiased predictor (BLUP)] more individuals are selected from the best families and so closely related individuals will generate most of the offspring. This effect is more important for traits with low heritability as phenotype gives little information on the breeding value of the individuals and more weight is given to relatives’ data. The need for controlling inbreeding refers not only to a better use of the genetic variability available and to a reduced inbreeding depression in the selected trait, but also to a reduced depression of fitness-related traits, which may be the most serious drawback at present due to the increase in inbreeding in domestic populations (M euwissen and W oolliams 1994). In recent years considerable work has been carried out on the design of strategies to maintain genetic diversity in selection programmes. These strategies are aimed at simultaneously optimizing genetic gain and inbreeding, either by reducing the rate of inbreeding (or variance of response) while keeping genetic gains at a predetermined level, or by increasing selection response under a restriction on inbreeding (or on variance of response). Following T oro and P& eacute; rez-E nciso (1990) the different strategies can be classified according to the factor on which they act: (i) the selection criterion used; (ii) the mating system imposed; (iii) the number of selected individuals and their contribution to the next generation. The first group of strategies proposes the use of a suboptimal selection criterion that reduces the weight given to family information or the use of an upward-biased heritability in BLUP evaluation (T oro and P& eacute; rez-E nciso 1990; see G rundy et al. 1998a for the latest development of this idea). The second group of strategies proposes action on the mating system including factorial mating designs, minimum co-ancestry mating (using linear programming) or compensatory mating (see review by C aballero et al. 1996). The third group of strategies includes the ones considered in the present work. The first possibility is to modify the contribution of the selected individuals of generation t to the selected individuals of generation t + 1, by practising some form of within-family selection with respect to BLUP values. Two strategies of this type were considered: modified within-family selection (MWFS) and restricted co-ancestry selection (RCS). The second possibility is to modify the contribution of the selected individuals of generation t to the evaluated individuals of generation t + 1 (instead of to the selected individuals) by a strategy called weighted selection (T oro and N ieto 1984). Three strategies were considered in this case: weighted selection (WS), restricted co-ancestry weighted selection (RCWS) and pair weighted selection (PWS). More specifically, the aim of the present paper is to show how these five strategies can be implemented using mathematical programming techniques. A small example comparing all of these strategies with standard truncation selection (TS) is also given for illustration.