Human tool culture seems to have influenced the evolution of human hand anatomy. Difficulties in ... more Human tool culture seems to have influenced the evolution of human hand anatomy. Difficulties in establishing a causal connection centre on the fact that early hominin hand anatomies supportive of tool culture precede the earliest tools in the archaeological record. Various considerations suggest that the archaeological record may be misleading. Earlier tools would not be visible if they were manufactured from wood or plant material, or if they were natural objects subject to only slight modification. Moreover, the first appearance of stone tools in the record may reflect a switch in the location of home bases or butchering sites, and not the commencement of stone tool usage. Acquisition of modern human tool skills is generally via imitation. There is no strong reason to suppose that a small-brained hominin such as Australopithecus was incapable of imitation, or that members of this genus could not have been manufacturers of stone tools. It therefore seems likely that anatomical sup...
While niche construction theory locates animal artefacts in their constructors’ environment, henc... more While niche construction theory locates animal artefacts in their constructors’ environment, hence treating them as capable of exerting selective pressure on both the constructors and their descendants, the extended phenotype concept assimilates artefacts with their constructors’ genes. Analogous contrasts apply in the case of endoparasite and brood parasite genes influencing host behaviour. The explanatory power of these competing approaches are assessed by re-examining the core chapters of Richard Dawkins’ The Extended Phenotype. Because animal artefacts (chapter 11) have multiple evolutionary consequences for their constructors, the extra-body effects of a gene seemingly include feedback effects on multiple other genes, a result which is more consistent with niche construction theory than with selfish gene theory. In the case of endoparasite genes influencing host behaviour (chapter 12), Dawkins’ argument leaves out what appears to be the key explanatory component, namely the role of the host’s own bodily systems in making it possible for such genes to exist. For action at a distance (chapter 13), it is unclear whether the key genes have extended effects because they sit in the body of the manipulating organism, or alternatively do not have such effects because they sit in the body of its victim. It is argued that niche construction theory offers a superior explanation in all three cases. Re-examination of these phenomena takes account of the fact that, despite Dawkins’ selfish gene approach, the extended phenotype concept is often interpreted in selfish organism terms.
Refugees from the current conflict in Syria have been exposed to a variety of stressors known to ... more Refugees from the current conflict in Syria have been exposed to a variety of stressors known to increase the risk of mental distress. These may include witnessing atrocities as well as dealing with the challenges of surviving in the displacement context. As a vast array of organisations rush to address mental health outcomes among Syrians, the scientific and conceptual validity of psychological tools used to assess and treat mental health difficulties becomes of paramount importance. Many psychological tools for assessing trauma have been validated in western contexts, but not among Syrians. This paper outlines three errors of reasoning which undermine the validity of psychological methods in cross-cultural contexts, including assuming that western psychiatric categories are universal constructs which can be applied in any context and failing to take contextual factors into account. Qualitative research may help us to better understand culturally specific conceptions of mental health. It is only once we have a solid understanding of how mental distress is understood and expressed among Syrian refugees that we can support effective interventions to alleviate it. The strengthening of indigenous health systems can help promote culturally appropriate mental health care.
Sexual coercion by males is generally understood to have three forms: forced copulation, harassme... more Sexual coercion by males is generally understood to have three forms: forced copulation, harassment and intimidation. We studied Australian brush-turkeys, Alectura lathami, to determine whether some male behaviours towards females at incubation mounds could be classified as aggressive, whether males were attempting sexual coercion and, if so, whether the coercion was successful. We found that some male behaviours towards females were significantly more likely to be followed by the cessation of female mound activity, and hence could be classified as aggressive, while others were significantly more likely to be followed by the commencement of female mound activity, and hence could be classified as enticing. Copulation was preceded by higher rates of male enticement and by higher rates of certain types of male aggression. It therefore seemed that males were attempting sexual coercion. There was little evidence, however, that this combination of coercion and enticement was successful in obtaining copulations. While forced copulation did occur, it was infrequent, and no evidence could be found for intimidation. We conclude that harassment is the primary form of sexual coercion by male brush-turkeys. Although sexual coercion is understood to be a sub-optimal tactic, brush-turkey sexual coercion was employed as a primary tactic by dominant males who owned incubation mounds. One possible explanation for this apparent paradox is that aggression is the default solution for social conflicts in this species, and hence can be interpreted as a behavioural syndrome.
Human tool culture seems to have influenced the evolution of human hand anatomy. Difficulties in ... more Human tool culture seems to have influenced the evolution of human hand anatomy. Difficulties in establishing a causal connection centre on the fact that early hominin hand anatomies supportive of tool culture precede the earliest tools in the archaeological record. Various considerations suggest that the archaeological record may be misleading. Earlier tools would not be visible if they were manufactured from wood or plant material, or if they were natural objects subject to only slight modification. Moreover, the first appearance of stone tools in the record may reflect a switch in the location of home bases or butchering sites, and not the commencement of stone tool usage. Acquisition of modern human tool skills is generally via imitation. There is no strong reason to suppose that a small-brained hominin such as Australopithecus was incapable of imitation, or that members of this genus could not have been manufacturers of stone tools. It therefore seems likely that anatomical sup...
While niche construction theory locates animal artefacts in their constructors’ environment, henc... more While niche construction theory locates animal artefacts in their constructors’ environment, hence treating them as capable of exerting selective pressure on both the constructors and their descendants, the extended phenotype concept assimilates artefacts with their constructors’ genes. Analogous contrasts apply in the case of endoparasite and brood parasite genes influencing host behaviour. The explanatory power of these competing approaches are assessed by re-examining the core chapters of Richard Dawkins’ The Extended Phenotype. Because animal artefacts (chapter 11) have multiple evolutionary consequences for their constructors, the extra-body effects of a gene seemingly include feedback effects on multiple other genes, a result which is more consistent with niche construction theory than with selfish gene theory. In the case of endoparasite genes influencing host behaviour (chapter 12), Dawkins’ argument leaves out what appears to be the key explanatory component, namely the role of the host’s own bodily systems in making it possible for such genes to exist. For action at a distance (chapter 13), it is unclear whether the key genes have extended effects because they sit in the body of the manipulating organism, or alternatively do not have such effects because they sit in the body of its victim. It is argued that niche construction theory offers a superior explanation in all three cases. Re-examination of these phenomena takes account of the fact that, despite Dawkins’ selfish gene approach, the extended phenotype concept is often interpreted in selfish organism terms.
Refugees from the current conflict in Syria have been exposed to a variety of stressors known to ... more Refugees from the current conflict in Syria have been exposed to a variety of stressors known to increase the risk of mental distress. These may include witnessing atrocities as well as dealing with the challenges of surviving in the displacement context. As a vast array of organisations rush to address mental health outcomes among Syrians, the scientific and conceptual validity of psychological tools used to assess and treat mental health difficulties becomes of paramount importance. Many psychological tools for assessing trauma have been validated in western contexts, but not among Syrians. This paper outlines three errors of reasoning which undermine the validity of psychological methods in cross-cultural contexts, including assuming that western psychiatric categories are universal constructs which can be applied in any context and failing to take contextual factors into account. Qualitative research may help us to better understand culturally specific conceptions of mental health. It is only once we have a solid understanding of how mental distress is understood and expressed among Syrian refugees that we can support effective interventions to alleviate it. The strengthening of indigenous health systems can help promote culturally appropriate mental health care.
Sexual coercion by males is generally understood to have three forms: forced copulation, harassme... more Sexual coercion by males is generally understood to have three forms: forced copulation, harassment and intimidation. We studied Australian brush-turkeys, Alectura lathami, to determine whether some male behaviours towards females at incubation mounds could be classified as aggressive, whether males were attempting sexual coercion and, if so, whether the coercion was successful. We found that some male behaviours towards females were significantly more likely to be followed by the cessation of female mound activity, and hence could be classified as aggressive, while others were significantly more likely to be followed by the commencement of female mound activity, and hence could be classified as enticing. Copulation was preceded by higher rates of male enticement and by higher rates of certain types of male aggression. It therefore seemed that males were attempting sexual coercion. There was little evidence, however, that this combination of coercion and enticement was successful in obtaining copulations. While forced copulation did occur, it was infrequent, and no evidence could be found for intimidation. We conclude that harassment is the primary form of sexual coercion by male brush-turkeys. Although sexual coercion is understood to be a sub-optimal tactic, brush-turkey sexual coercion was employed as a primary tactic by dominant males who owned incubation mounds. One possible explanation for this apparent paradox is that aggression is the default solution for social conflicts in this species, and hence can be interpreted as a behavioural syndrome.
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Papers by David Wells
assuming that western psychiatric categories are universal constructs which can be applied in any context and failing to take contextual factors into account. Qualitative research may help us to better understand culturally specific conceptions of mental health. It is only once we have a solid understanding of how mental distress is understood and expressed among Syrian refugees that we can support effective interventions to alleviate it. The strengthening of indigenous health systems can help promote culturally appropriate mental health care.
assuming that western psychiatric categories are universal constructs which can be applied in any context and failing to take contextual factors into account. Qualitative research may help us to better understand culturally specific conceptions of mental health. It is only once we have a solid understanding of how mental distress is understood and expressed among Syrian refugees that we can support effective interventions to alleviate it. The strengthening of indigenous health systems can help promote culturally appropriate mental health care.