Focus: Addiction: Relapse Prevention and the Five Rules of Recovery

There are four main ideas in relapse prevention. First, relapse is a gradual process with distinct stages. The goal of treatment is to help individuals recognize the early stages, in which the chances of success are greatest. Second, recovery is a process of personal growth with developmental milestones. Each stage of recovery has its own risks of relapse. Third, the main tools of relapse prevention are cognitive therapy and mind-body relaxation, which are used to develop healthy coping skills. Fourth, most relapses can be explained in terms of a few basic rules. Educating clients in these rules can help them focus on what is important: 1) change your life (recovery involves creating a new life where it is easier to not use); 2) be completely honest; 3) ask for help; 4) practice self-care; and 5) don’t bend the rules.     

Degradation of met-enkephalin by extracts of various regions of the human brain: effects of antipsychotics and narcotics in vitro

Antischizophrenic drugs, reduced in a concentration-dependent fashion enkephalin degradation by the soluble and particulate fractions of the human cerebral cortex and cerebellum. The order of potency is as follows: thioridazine greater than chlorpromazine greater than fluphenazine greater than haloperidol greater than or equal to promazine with IC50 of 50, 80, 120, 200-250 micro M, respectively. Kinetic studies revealed non-competitive and competitive inhibition by thioridazine and chlorpromizine, respectively. Narcotics, were weak inhibitors of enkephalin degradation. For dl-, d-, l-methadone and l-alpha-acetylmethadol, IC50 was about 500 micro M, and 1000 micro M for heroin and morphine. It is suggested that inhibition of the degradation of endogenous morphinomimetic peptides in the CNS may be a crucial factor governing the pharmacology of some neuroleptics and other psychoactive drugs. Enkephalin-hydrolyzing activity was ubiquitous and exhibited considerable regional differences in the normal human and in Huntington's chorea brains. The rate of enkephalin degradation is generally higher in the subcortical nuclei than in the cortex and cerebellum. The highest hydrolytic activity was found in the substantia nigra, anterior thalamus, septal area, globus pallidus and caudate nucleus, in this decreasing order.     

The change in the attitudes of Czech hunters towards Eurasian lynx: Is poaching restricting lynx population growth?

Even though the Eurasian lynx is a less controversial species than the wolf or brown bear, poaching remains a major cause of lynx mortality in Europe, potentially threatening population expansion in key areas. Our study was designed to explore the attitude of hunters and other stakeholders (students of secondary forestry schools and University forestry faculties) towards lynx and their experience with illegal killing of lynx in the Czech Republic. Self-administered questionnaires were addressed to local hunters and to students in 2001 and again in 2015. The survey in 2001 was conducted in two separate hunting regions of Bohemia, one where lynx have been artificially reintroduced and another in which lynx have become established through natural colonisation. In 2015 the survey was extended to two further areas where lynx have re-established themselves through natural colonisation, in the east of the Czech Republic. Altogether 415 and 922 questionnaires were completed in 2001 and 2015, respectively. The attitude of hunters towards lynx was not affected by hunting region, lynx population density or nature of the population (human re-introductions vs natural recolonisation), but attitudes became more negative in 2015 than they had been in 2001. The majority of hunters still believed that lynx had negative effects on other wildlife and 27% stated that they do not wish to co-exist with lynx. Half of secondary school students and a third of tertiary students still believe that lynx threaten roe deer stocks, even though roe and red deer are present at high density and cause extensive damage in commercial forestry. Hunters as well as forestry students had first-hand knowledge about illegal hunting of lynx. The proportion of hunters admitting to having poached lynx themselves was 10% with the proportion of repeated illegal kills made by the same person increasing between 2001 and 2015. Population modelling suggested that at least 25% of the population might be poached annually, sufficient to restrict population growth and further expansion of lynx distribution.     

PATTERNS OF VARIATION AND LINKAGE DISEQUILIBRIUM IN A FIELD CRICKET HYBRID ZONE

The distribution of multilocus genotypes found within a natural hybrid zone is determined by the sample of genotypes present when the hybrid zone first formed, by subsequent patterns of genetic exchange between the hybridizing taxa, and by drift and selection within each of the hybrid zone populations. We have used anonymous nuclear DNA restriction fragment polymorphisms (RFLPs) to characterize the array of multilocus genotypes present within a well-studied hybrid zone between two eastern North American field crickets, Gryllus pennsylvanicus and Gryllus firmus. These crickets hybridize along a zone of contact that extends from New England to Virginia. Previous studies have shown that both premating and postmating barriers exist between the two cricket species, but the absence of diagnostic morphological and allozyme markers has made it difficult to assess the consequences of these barriers for genetic exchange. Analyses based on four diagnostic anonymous nuclear markers indicate that hybrid zone populations in Connecticut contain few F₁ hybrids, and that nonrandom associations persist among nuclear gene markers, between nuclear and cytoplasmic markers, and between molecular markers and morphology. Field cricket populations within the hybrid zone are not “hybrid swarms” but consist primarily of crickets that are very much like one or the other of the parental species. Despite ample opportunity for genetic exchange and evidence for introgression at some loci, the two species remain quite distinct. Such a pattern appears to be characteristic of many natural hybrid zones.     

One-shot reciprocity under error management is unbiased and fragile

The error management model of altruism in one-shot interactions provides an influential explanation for one of the most controversial behaviors in evolutionary social science. The model posits that one-shot altruism arises from a domain-specific cognitive bias that avoids the error of mistaking a long-term relationship for a one-shot interaction. One-shot altruism is thus, in an intriguingly paradoxical way, a form of reciprocity. We examine the logic behind this idea in detail. In its most general form the error management model is exceedingly flexible, and restrictions about the psychology of agents are necessary for selection to be well-defined. Once these restrictions are in place, selection is well defined, but it leads to behavior that is perfectly consistent with an unbiased rational benchmark. Thus, the evolution of one-shot reciprocity does not require an evoked cognitive bias based on repeated interactions and reputation. Moreover, in spite of its flexibility in terms of psychology, the error management model assumes that behavior is exceedingly rigid when individuals face a new interaction partner. Reciprocity can only take the form of tit-for-tat, and individuals cannot adjust their behavior in response to new information about the duration of a relationship. Zefferman (2014) showed that one-shot reciprocity does not reliably evolve if one relaxes the first restriction, and we show that the behavior does not reliably evolve if one relaxes the second restriction. Altogether, these theoretical results on one-shot reciprocity do not square well with experiments showing increased altruism in the presence of payoff-irrelevant stimuli that suggest others are watching.     

DIVERGENCE ACROSS AUSTRALIA'S CARPENTARIAN BARRIER: STATISTICAL PHYLOGEOGRAPHY OF THE RED‐BACKED FAIRY WREN (MALURUS MELANOCEPHALUS)

Multilocus analysis of phylogeography and population history is a powerful tool for understanding the origin, dispersal, and geographic structure of species over time and space. Using 36 genetic markers (29 newly developed anonymous nuclear loci, six introns and one from mitochondrial DNA, amounting to over 15 kb per individual), we studied population structure and demographic history of the red‐backed fairy wren Malurus melanocephalus, a small passerine distributed in the northern and eastern part of Australia across the Carpentarian barrier. Analysis of anonymous loci markers revealed large amounts of genetic diversity (π= 0.016 ± 0.01; average number of SNPs per locus = 48; total number of SNPs = 1395), and neither nuclear nor mitochondrial gene trees showed evidence of reciprocal monophyly among Cape York (CY), Eastern Forest (EF), and Top End (TE) populations. Despite traditional taxonomy linking TE and CY populations to the exclusion of EF, we found that the CY population is genetically closer to the EF population, consistent with predicted area cladograms in this region. Multilocus coalescent analysis suggests that the CY population was separated from the other two regions approximately 0.27 million years ago, and that significant gene flow between the ER and the CY populations (～2 migrants per generation) suggests geographic continuity in eastern Australia. By contrast, gene flow between the CY and the TE populations has been dampened by divergence across the Carpentarian barrier.     

MOLECULAR DEMOGRAPHIC HISTORY OF THE ANNUAL SUNFLOWERS HELIANTHUS ANNUUS AND H. PETIOLARIS—LARGE EFFECTIVE POPULATION SIZES AND RATES OF LONG-TERM GENE FLOW

Hybridization between distinct species may lead to introgression of genes across species boundaries, and this pattern can potentially persist for extended periods as long as selection at some loci or genomic regions prevents thorough mixing of gene pools. However, very few reliable estimates of long-term levels of effective migration are available between hybridizing species throughout their history. Accurate estimates of divergence dates and levels of gene flow require data from multiple unlinked loci as well as an analytical framework that can distinguish between lineage sorting and gene flow and incorporate the effects of demographic changes within each species. Here we use sequence data from 18 anonymous nuclear loci in two broadly sympatric sunflower species, Helianthus annuus and H. petiolaris , analyzed within an "isolation with migration" framework to make genome-wide estimates of the ages of these two species, long-term rates of gene flow between them, and effective population sizes and historical patterns of population growth. Our results indicate that H. annuus and H. petiolaris are approximately one million years old and have exchanged genes at a surprisingly high rate (long-term N_efm estimates of approximately 0.5 in each direction), with somewhat higher rates of introgression from H. annuus into H. petiolaris than vice versa. In addition, each species has undergone dramatic population expansion since divergence, and both species have among the highest levels of genetic diversity reported for flowering plants. Our results provide the most comprehensive estimate to date of long-term patterns of gene flow and historical demography in a nonmodel plant system, and they indicate that species integrity can be maintained even in the face of extensive gene flow over a prolonged period.     

The face of another: anonymity and facial symmetry influence cooperation in social dilemmas

In the present paper, we study how the morphological features related to developmental physiology of other participants influence the decision to cooperate in a social dilemma. To that end, we let a large sample of men play a prisoner's dilemma game, both anonymously and against a series of counterparts whose photographs were shown. We focus on three characteristics already linked to cooperative behavior and with described effects on the adult facial shape: facial fluctuating asymmetry, a frequently employed but debated proxy for developmental instability; the degree of facial dimorphism, related to levels of testosterone during puberty; and the second to fourth digit ratio, related to relative prenatal testosterone exposure. We find significantly higher cooperation rates in anonymous interactions than in the non-anonymous round. We also find that individuals are more likely to cooperate with more asymmetric counterparts, and that more asymmetric participants were less likely to believe that their counterpart would cooperate. Variables related to exposure to testosterone during development do not display any effect. We conclude by discussing how out-of-the-game rewards can explain our results.