Should Autism Spectrum Conditions Be Characterised in a More Positive Way in Our Modern World?

In a special issue that focuses on complex presentations related to Autism, we ask the question in this editorial whether an Autism Spectrum Condition without complexity is a disorder, or whether it represents human diversity? Much research into Autism Spectrum Conditions (ASCs) over the years has focused on comparisons between neuro-typical people and people with Autism Spectrum Conditions. These comparisons have tended to draw attention to 'deficits' in cognitive abilities and descriptions of behaviours that are characterised as unwanted. Not surprisingly, this is reflected in the classification systems from the World Health Organisation and the American Psychiatric Association. Public opinion about ASC may be influenced by presentations in the media of those with ASC who also have intellectual disability. Given that diagnostic systems are intended to help us better understand conditions in order to seek improved outcomes, we propose a more constructive approach to descriptions that uses more positive language, and balances descriptions of deficits with research finding of strengths and differences. We propose that this will be more helpful to individuals on the Autism Spectrum, both in terms of individual self-view, but also in terms of how society views Autism Spectrum Conditions more positively. Commentary has also been made on guidance that has been adjusted for people with ASC in relation to the current COVID-19 pandemic.

Theoretical and Methodological Approaches to Ecological Changes, Social Behaviour and Human Intergroup Tolerance 300,000 to 30,000 BP.

Archaeological evidence suggests that important shifts were taking place in the character of human social behaviours 300,000 to 30,000 years ago. New artefact types appear and are disseminated with greater frequency. Transfers of both raw materials and finished artefacts take place over increasing distances, implying larger scales of regional mobility and more frequent and friendlier interactions between different communities. Whilst these changes occur during a period of increasing environmental variability, the relationship between ecological changes and transformations in social behaviours is elusive. Here, we explore a possible theoretical approach and methodology for understanding how ecological contexts can influence selection pressures acting on intergroup social behaviours. We focus on the relative advantages and disadvantages of intergroup tolerance in different ecological contexts using agent-based modelling (ABM). We assess the relative costs and benefits of different 'tolerance' levels in between-group interactions on survival and resource exploitation in different environments. The results enable us to infer a potential relationship between ecological changes and proposed changes in between-group behavioural dynamics. We conclude that increasingly harsh environments may have driven changes in hormonal and emotional responses in humans leading to increasing intergroup tolerance, i.e. transformations in social behaviour associated with 'self-domestication'. We argue that changes in intergroup tolerance is a more parsimonious explanation for the emergence of what has been seen as 'modern human behaviour' than changes in hard aspects of cognition or other factors such as cognitive adaptability or population size. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10816-020-09503-5.

A Major Change in Rate of Climate Niche Envelope Evolution during Hominid History.

Homo sapiens is the only species alive able to take advantage of its cognitive abilities to inhabit almost all environments on Earth. Humans are able to culturally construct, rather than biologically inherit, their occupied climatic niche to a degree unparalleled within the animal kingdom. Precisely, when hominins acquired such an ability remains unknown, and scholars disagree on the extent to which our ancestors shared this same ability. Here, we settle this issue using fine-grained paleoclimatic data, extensive archaeological data, and phylogenetic comparative methods. Our results indicate that whereas early hominins were forced to live under physiologically suitable climatic conditions, with the emergence of H. heidelbergensis, the Homo climatic niche expanded beyond its natural limits, despite progressive harshening in global climates. This indicates that technological innovations providing effective exploitation of cold and seasonal habitats predated the emergence of Homo sapiens.

Supraorbital morphology and social dynamics in human evolution.

Uniquely, with respect to Middle Pleistocene hominins, anatomically modern humans do not possess marked browridges, and have a more vertical forehead with mobile eyebrows that play a key role in social signalling and communication. The presence and variability of browridges in archaic Homo species and their absence in ourselves have led to debate concerning their morphogenesis and function, with two main hypotheses being put forward: that browridge morphology is the result of the spatial relationship between the orbits and the brain case; and that browridge morphology is significantly impacted by biting mechanics. Here, we virtually manipulate the browridge morphology of an archaic hominin (Kabwe 1), showing that it is much larger than the minimum required to fulfil spatial demands and that browridge size has little impact on mechanical performance during biting. As browridge morphology in this fossil is not driven by spatial and mechanical requirements alone, the role of the supraorbital region in social communication is a potentially significant factor. We propose that conversion of the large browridges of our immediate ancestors to a more vertical frontal bone in modern humans allowed highly mobile eyebrows to display subtle affiliative emotions.