The evolution of language: a comparative review

For many years the evolution of language has been seen as a disreputable topic, mired in fanciful "just so stories" about language origins. However, in the last decade a new synthesis of modern linguistics, cognitive neuroscience and neo-Darwinian evolutionary theory has begun to make important contributions to our understanding of the biology and evolution of language. I review some of this recent progress, focusing on the value of the comparative method, which uses data from animal species to draw inferences about language evolution. Discussing speech first, I show how data concerning a wide variety of species, from monkeys to birds, can increase our understanding of the anatomical and neural mechanisms underlying human spoken language, and how bird and whale song provide insights into the ultimate evolutionary function of language. I discuss the ‘‘descended larynx’ ’ of humans, a peculiar adaptation for speech that has received much attention in the past, which despite earlier claims is not uniquely human. Then I will turn to the neural mechanisms underlying spoken language, pointing out the difficulties animals apparently experience in perceiving hierarchical structure in sounds, and stressing the importance of vocal imitation in the evolution of a spoken language. Turning to ultimate function, I suggest that communication among kin (especially between parents and offspring) played a crucial but neglected role in driving language evolution. Finally, I briefly discuss phylogeny, discussing hypotheses that offer plausible routes to human language from a non-linguistic chimp-like ancestor. I conclude that comparative data from living animals will be key to developing a richer, more interdisciplinary understanding of our most distinctively human trait: language

Trends in gonorrhoea in nine western European countries, 1991-6. European Study Group.

&lt;p&gt;&lt;b&gt;OBJECTIVE: &lt;/b&gt;To present, describe, and assess trends in gonorrhoea in western Europe between 1991 and 1996.&lt;/p&gt;&lt;p&gt;&lt;b&gt;METHODS: &lt;/b&gt;A European Union concerted action was initiated in 1990 to monitor the prevalence of HIV among patients with a sexually transmitted infection in sentinel networks in western Europe. Data from this concerted action were used to assess trends in gonorrhoea between 1991 and 1996. Where possible, the trends were validated by comparing them with national laboratory reports or data from more extensive sexually transmitted infection surveillance networks.&lt;/p&gt;&lt;p&gt;&lt;b&gt;RESULTS: &lt;/b&gt;7192 episodes of gonorrhoea were recorded at 38 sentinel sites in nine countries between 1991 and 1996. In most networks, there was a decline in the number of cases of gonorrhoea among heterosexual men and women. The decline was most marked in the Scandinavian countries. Decreases were also observed among men having sex with men, but in some networks--England and Wales, Netherlands, and Scotland--an increase was observed in more recent years. This increase was mainly the result of an increase in cases among the older age group (25 years and above). The trends observed in six of the sentinel networks were confirmed by trends in national laboratory reports or data from more extensive sexual transmitted infection surveillance systems.&lt;/p&gt;&lt;p&gt;&lt;b&gt;CONCLUSIONS: &lt;/b&gt;These data indicate that, overall, there was a decline in the number of gonorrhoea cases in western Europe between 1991 and 1996. The results, however, also indicate that in more recent years there was an increase in the number of gonorrhoea cases among men having sex with men in some countries. Further investigations are necessary to determine if this observation is due to an increase in risky sexual behaviours in this population group.&lt;/p&gt;</p

Contactless and Spatially Resolved Determination of Current-Voltage Curves in Perovskite Solar Cells via Photoluminescence

Early prediction of spatially resolved performance of perovskite solar cells (PSCs) is essential for process monitoring, control and fault diagnosis, and upscaling of this emerging technology. Herein, a fast, nonde structive, contactless imaging-based approach is developed to visualize the spatial distribution of possible light current density−voltage (pseudo-J−V) curves on finished and partly finished cells. This allows for the extraction of other critical spatially resolved properties including implied open-circuit voltage and pseudo-fill factor. The technique is applied to systematically investigate various degradation behaviors on PSCs including thermal stability, light soaking, and ambient air exposure. Finally, it is used to predict pseudo-J−V curves of various perovskite films with different compositions. These results demonstrate the significant value of this fast imaging technique for the research and development of PSCs ranging from material selection, process optimization, to degradation study