Non-bizarre psychotic delusions are hypothesized to be psychological adaptations which evolved to mitigate the dangerous consequences of social exclusion and ostracism. When we lived in small, kin-based groups, delusions would have functioned to combat social exclusion by closely mimicking conditions, such as external threats or illness, where fellow group members were likely to cooperate and provide assistance. If delusions are adaptations to social exclusion, then they should onset when an individual faces a serious social threat, they should function (in ancestral type environments) to prevent exclusion-at least in the short term-and they should cease when the social threat ceases, an hypothesis which is examined in the context of numerous published studies of Delusional Disorder (DD).
Long before the term Machiavellian Intelligence was coined, James Neel, a prominent geneticist, was pondering the role of 'princes' in the evolution of exceptional human intelligence. Neel discovered that in small-scale societies resembling those in which humans evolved, leaders had more wives and more children than other men. If this pattern, which is now well-established in the ethnographic record, characterized ancestral human societies, whatever traits predisposed men to become leaders would have experienced strong sexual selection. Neel proposed that the key trait was intelligence. Sexual selection on intelligent leaders therefore helped explain human encephalization. Many subsequent theories have attempted to explain why knowledgeable, skilled, and intelligent individuals are chosen as leaders or as mates. None, however, has adequately explained why they are chosen as both. We aim to fill this gap by operationalizing leaders as individuals who regularly make decisions that benefit most members of the group. Because human nuclear families comprise two unrelated individuals who cooperate for twenty years or more to raise their joint offspring, and because families are nested within subsistence groups, which, in turn, are nested within larger security and political groups, good decision-making skills provided large benefits to mates and families, as well as to members of one's subsistence group or larger security and political groups. We further argue that decision-making that benefits others as well as oneself can be especially computationally complex, and therefore that sexual selection and biological market forces favoring these skills favored increased brain size. Finally, because parents must make decisions for their cognitively immature offspring, decision-making that benefits others and other leadership abilities might have initially undergone strong selection in mothers, who provide most of the childcare in natural fertility populations. Decision-making that benefits others is one valuable example of what we term a computational service. Other important examples include threat and opportunity detection, gossip and information sharing, cultural transmission, story telling, medicinal knowledge, and advice and counsel. Providing computational services in exchange for a variety of benefits would have helped subsidize a large, energetically expensive brain. Individuals who provided particularly valuable services gained prestige, i.e., additional benefits from fellow group members.
Abstract We applaud Müller & Schumann (M&S) for bringing needed attention to the problem of motivation for common non-addictive drug use, as opposed to the usual focus on exotic drugs and addiction. Unfortunately, their target article has many underdeveloped and sometimes contradictory ideas. Here, we will focus on three key issues.
Genealogy has been a pillar of anthropological research since the earliest ethnographic fieldwork. A turn toward demographically and quantitatively oriented kinship studies in the 1960s highlighted the need for more systematic genealogical methods. New computer-assisted, iterative field methods were developed in response. These methods can dramatically improve data quality and quantity and are remarkably flexible. Here, the authors outline an iterative genealogical approach that has been used to study kinship, migration, education, alcoholism, food sharing, intragroup aggression, father absence, community fissioning, and land ownership. The authors demonstrate the reliability of these data and show how they can be analyzed. The unobtrusive genealogical methods outlined here could be used to study terminologies and cognitive models of kinship; however, the authors focus on applications to demography, epidemiology, and economics.
Buller recently posted a critique of evolutionary psychology (reproduced below). Although I disagree with many of his assertions, this is the most credible attempt to critique evolutionary psychology that I have encountered. Bullers arguments regarding improper motivational inferences from evolutionary psychological explanations are largely correct--such inferences are indeed erroneous. Furthermore, the mistakes he identifies have been made by some prominent evolutionists including, apparently, W. D. Hamilton (Symons, personal communication). However, most evolutionary psychologists are not saying what he claims they are saying. Buller wishes to find evolutionary psychology trapped in Freudian quicksand so that he can rescue it. Instead, it is he who must hoist himself from the bog using the theoretical rigging created by evolutionary psychologists over the last two decades, including, most prominently, Don Symons, a primary target of his essay.
Most adults regularly use at least one psychoactive drug. Globally popular options include caffeine (found in coffee, tea, soft drinks, and chocolate), alcohol, nicotine, arecoline and other psychoactive compounds in areca nuts (i.e., betel nuts, used by 10-20% of the global population), THC and other cannabinoids, opioids, amphetamine and its chemical analogs found in khat and other plants, and cocaine. Few realize, however, the extraordinary time depth in which people have been interacting with these plants. In many cases, psychoactive plants used by prehistoric humans have in recent times been refined into incredibly potent and addictive substances, with profound global health consequences. Studies that investigate the evolutionary history of psychoactive drug use by humans provide a deep time perspective on addiction, self-medication, and other complex cultural and physical interactions of psychoactive substances. In this chapter Hagen and Tushingham provide a wide ranging account of psychoactive drug use by worldwide human cultures, past and present. This includes a synthetic treatment of major scientific theories of intoxicant use by hominins, as well as a review of analytical techniques and major archaeological discoveries that track a wide range of substances.
