Balancing acts: Picturing perspiration in the long eighteenth century

This essay examines the historical fortunes of an image that throughout the seventeenth and eighteenth centuries became a landmark of the medical doctrine and practice of static medicine advanced by the physician Santorio Santorio (1561-1636). The image depicted a man sitting on a large Roman steelyard, which allowed the weighing of bodily discharges and gave guidance on the intake of food. Well into the eighteenth century, the image of the weight-watching man accompanied Santorio's work on the art of static medicine and, most likely, contributed to its success. It appeared in a variety of medical works and navigated across competing medical theories and different medical genres, while remaining largely unscathed. This essay explores the success and the historical agency of this image. Focusing on the history of its copies and variants, it investigates how the image came to symbolize the attempt to transform dietetics into an experimental practice, and accordingly preserve its pivotal significance in the medical world.     

Self-awareness and the emergence of mind in primates

To date humans, chimpanzees, and orangutans are the only species which have been shown capable of recognizing themselves in mirrors. Several species of macaques have now been provided with years of continuous exposure to mirrors, but they still persist in reacting to their reflection as if they were seeing other monkeys. Even gibbons (apes) and gorillas (great apes) seem incapable of learning that their behavior is the source of the behavior depicted in the image. Most primates, therefore, appear to lack a cognitive category for processing mirrored information about themselves. The implications of these data for traditional views of consciousness are considered briefly, and a recent attempt to develop an operant analog to self-recognition is critically evaluated. Finally, an attempt is made to show that self-awareness, consciousness, and mind are not mutually exclusive cognitive categories and that the emergence of self-awareness may be equivalent to the emergence of mind. Several indices of “mind” which can be applied to nonhuman species are discussed in the context of an attempt to develop a comparative psychology of mind.     

Collaborative production and experimental labor: two models of dissertation authorship in the eighteenth century

This article examines two early modern models of dissertation authorship that both relied on extensive collaboration between the degree candidate and his supervisor. The dissertation conducted on the traditional model, practiced until the eighteenth century at German universities, was a joint product of the supervisor, who prepared the thesis in writing, and the degree candidate, who defended it in the oral disputation. The two collaborators shared the credit for a successfully defended thesis in different forms: right for public recognition and rights to use and reproduce the thesis. Instead of sharing the credit as two equal partners, each of them took advantage of his credit in ways that benefited his status. In the model that Albrecht von Haller introduced at Göttingen, the supervisor provided the student with a laboratory and experimental training, while the degree candidate wrote a thesis by himself based on the experiments he carried out, and defended the thesis without the supervisor chairing the disputation. The Haller model reveals two new elements that heralded the development of modern scientific education: divisibility of laboratory labor between the student’s experimentation and the research program to which it belongs; and feasibility of the requirement of experimental work in return for the exclusive authorship of the doctoral thesis.     

Physical stature of men in eighteenth century Mexico: Evidence from Puebla

We present a first glimpse of the mean height of men in eighteenth century Mexico based on evidence from the Revillagigedo Census of 1791–1792. Mexican men were shorter than those of Europe and North America. For example, contemporary French men were about 165 cm and US men were about 174 cm; in contrast, Mexican men were about 162 cm. Men of higher income were taller than those in the middle and lower income strata. Mestizos (a mix of whites and Indians) were shorter than the rest of the recruits belonging to other ethnic categories.     

Birth spacing and infant mortality: evidence for eighteenth and nineteenth century German villages

Data from an historical population in which fertility control was minimal and modern health services were mostly unavailable are used to show that there appears to have been a strong association between previous birth interval length and infant mortality, especially when the previous child survived. Although only imperfect proxies for breast-feeding practices and other potentially confounding factors are available for this population, the results suggest that the association between previous interval length and infant mortality in this population is not solely, or primarily, a function of differences in breast-feeding behaviour or socioeconomic status. Other factors, e.g. maternal depletion or sibling competition, are more likely to explain the observed association.     

Genomic analysis of the emergence of 20th century epidemic dysentery

Background

Shigella dysenteriae type 1 (Sd1) causes recurrent epidemics of dysentery associated with high mortality in many regions of the world. Sd1 infects humans at very low infectious doses (10 CFU), and treatment is complicated by the rapid emergence of antibiotic resistant Sd1 strains. Sd1 is only detected in the context of human infections, and the circumstances under which epidemics emerge and regress remain unknown.

Results

Phylogenomic analyses of 56 isolates collected worldwide over the past 60 years indicate that the Sd1 clone responsible for the recent pandemics emerged at the turn of the 20^th century, and that the two world wars likely played a pivotal role for its dissemination. Several lineages remain ubiquitous and their phylogeny indicates several recent intercontinental transfers. Our comparative genomics analysis reveals that isolates responsible for separate outbreaks, though closely related to one another, have independently accumulated antibiotic resistance genes, suggesting that there is little or no selection to retain these genes in-between outbreaks. The genomes appear to be subjected to genetic drift that affects a number of functions currently used by diagnostic tools to identify Sd1, which could lead to the potential failure of such tools.

Conclusions

Taken together, the Sd1 population structure and pattern of evolution suggest a recent emergence and a possible human carrier state that could play an important role in the epidemic pattern of infections of this human-specific pathogen. This analysis highlights the important role of whole-genome sequencing in studying pathogens for which epidemiological or laboratory investigations are particularly challenging.

Electronic supplementary material

The online version of this article (doi: 10.1186/1471-2164-15-355) contains supplementary material, which is available to authorized users.     

The emergence of emergence: a critique of "design, observation, surprise!".

Artificial life research begins from the premise that Alife subsumes real life. A criterion for emergence in Alife has been formulated that, however, excludes real life and postulates the need for a real life Designer and an Observer. This in effect nullifies the premise of Alife and takes us back to the argument for God from design of Bishop Paley in 1802. An alternative is to realize that Alife could include two properties: simulated organisms that both design themselves and are the observers. Self-design can come about via evolution in a population of mating organisms, especially via mutations that are gene or higher order duplications. Duplications permit novelty while retaining previously attained functions. The ability to observe can itself evolve, if its construction process evolves. This may now be possible to simulate, if new paradigms for embryogenesis, such as positional information or differentiation waves, prove accurate, or at least sufficiently robust to construct a wide diversity of observational abilities. The evolution of perception, however, may be limited by the physics available to the Alife organisms, which can come in three forms: simulated physics, real physics accessible to robots, or "Cyberspace physics".     

The invasion of language: emergence, change and death

Research into the emergence and evolution of human language has received unprecedented attention during the past 15 years. Efforts to better understand the processes of language emergence and evolution have proceeded in two main directions: from the top-down (linguists) and from the bottom-up (cognitive scientists). Language can be viewed as an invading process that has had profound impact on the human phenotype at all levels, from the structure of the brain to modes of cultural interaction. In our view, the most effective way to form a connection between the two efforts (essential if theories for language evolution are to reflect the constraints imposed on language by the brain) lies in computational modelling, an approach that enables numerous hypotheses to be explored and tested against objective criteria and which suggest productive paths for empirical researchers to then follow. Here, with the aim of promoting the cross-fertilization of ideas across disciplines, we review some of the recent research that has made use of computational methods in three principal areas of research into language evolution: language emergence, language change, and language death.     

From hormones to secondary metabolism: the emergence of metabolic gene clusters in plants

Gene clusters for the synthesis of secondary metabolites are a common feature of microbial genomes. Well-known examples include clusters for the synthesis of antibiotics in actinomycetes, and also for the synthesis of antibiotics and toxins in filamentous fungi. Until recently it was thought that genes for plant metabolic pathways were not clustered, and this is certainly true in many cases; however, five plant secondary metabolic gene clusters have now been discovered, all of them implicated in synthesis of defence compounds. An obvious assumption might be that these eukaryotic gene clusters have arisen by horizontal gene transfer from microbes, but there is compelling evidence to indicate that this is not the case. This raises intriguing questions about how widespread such clusters are, what the significance of clustering is, why genes for some metabolic pathways are clustered and those for others are not, and how these clusters form. In answering these questions we may hope to learn more about mechanisms of genome plasticity and adaptive evolution in plants. It is noteworthy that for the five plant secondary metabolic gene clusters reported so far, the enzymes for the first committed steps all appear to have been recruited directly or indirectly from primary metabolic pathways involved in hormone synthesis. This may or may not turn out to be a common feature of plant secondary metabolic gene clusters as new clusters emerge.