Culture and biology in the origins of linguistic structure

Language is systematically structured at all levels of description, arguably setting it apart from all other instances of communication in nature. In this article, I survey work over the last 20 years that emphasises the contributions of individual learning, cultural transmission, and biological evolution to explaining the structural design features of language. These 3 complex adaptive systems exist in a network of interactions: individual learning biases shape the dynamics of cultural evolution; universal features of linguistic structure arise from this cultural process and form the ultimate linguistic phenotype; the nature of this phenotype affects the fitness landscape for the biological evolution of the language faculty; and in turn this determines individuals’ learning bias. Using a combination of computational simulation, laboratory experiments, and comparison with real-world cases of language emergence, I show that linguistic structure emerges as a natural outcome of cultural evolution once certain minimal biological requirements are in place

Moving closer to reach the top:approach behavior increases one's sense of power

Power holders exhibit more approach behavior than those without power and are even expected by others to do so. We proposed that this strong association between power and approach should make approach behavior a useful cue for perceiving one’s level of power: If I am approaching things, I must be powerful. Across three experiments, engaging in approach behavior led individuals to feel explicitly (Exp. 1) and implicitly (Exp. 2) more powerful and to feel better suited for high-power jobs (Exp. 3), without affecting conscious affective experiences. Furthermore, the effect was not dependent on specific physical movements; the same movement was psychologically framed as either approach or avoidance and affected participants’ sense of power accordingly (Exp. 1 & 3). Since power itself leads to approach behavior, these results suggest a way power hierarchies may be unintentionally perpetuated or strengthened

Palladosilicide, Pd2Si, a new mineral from the Kapalagulu Intrusion, Western Tanzania and the Bushveld Complex, South Africa

© 2015 The Mineralogical Society. This document is the author's submitted/pre-refereeing version of the journal article. You are advised to consult the publisher's version if you wish to cite from it

Irrigation water quality and the threat it poses to crop production: evaluating the status of the Crocodile (West) and Marico catchments, South Africa

Ensuring food security is becoming increasingly difficult due to limited freshwater resources. Low-quality irrigation water also poses a severe threat to crop yield and quality. The aim of this study was to evaluate the water quality associated with the Crocodile (West) and Marico catchments, which represent one of South Africa’s most developed regions. Sources of irrigation water include the hypertrophic Hartbeespoort Dam, as well as the heavily impacted Crocodile (West) River. Analysis of historical irrigation water quality data (from January 2005 to December 2015) revealed that the Hartbeespoort and Crocodile (West) irrigation schemes were exposed to calcium sulfate enrichment, likely as a result of extensive mining activities in the Bushveld Igneous Complex. Also, significant differences in water quality parameters occurred between these irrigation schemes and the reference system (Marico-Bosveld Irrigation Scheme), while important salt (chloride and sodium) and nutrient (inorganic nitrogen and orthophosphate (as phosphorus)) concentrations exceeded threshold values provided by irrigation water quality guidelines. The Hartbeespoort and Crocodile (West) irrigation schemes also presented distinctive temporal (long-term and seasonal) patterns in water quality. Seasonal variation in pH levels at the Hartbeespoort Irrigation Scheme is likely caused by excessive algae growth and cyanobacteria blooms (Mycrocystis sp.), which also pose an important threat to human and animal health. Despite mitigation efforts by government and other stakeholders, some of South Africa’s major irrigation schemes remain highly impacted as a result of water quality deterioratio