Neuroscience, evolution, and culture

Tag Archives: lifestyle

The Logic of Fashion Cycles

As announced a few weeks ago, our paper “The Logic of Fashion Cycles” has been published, and is freely available on the PLoS ONE website. You can find a good summary at The National Post.

New paper: The logic of fashion cycles

Plos ONE has accepted our paper “The logic of fashion cycles,” where Alberto Acerbi, Magnus Enquist and myself present a new theoretical model to understand fashion cycles (see my previous post on dog breeds). You can download a preprint, and here is the abstract:

Many cultural traits exhibit volatile dynamics, commonly dubbed fashions or fads. Here we show that realistic fashion-like dynamics emerge spontaneously if individuals can copy others’ preferences for cultural traits as well as traits themselves. We demonstrate this dynamics in simple mathematical models of the diffusion, and subsequent abandonment, of a single cultural trait which individuals may or may not prefer. We then simulate the coevolution between many cultural traits and the associated preferences, reproducing power-law frequency distributions of cultural traits (most traits are adopted by few individuals for a short time, and very few by many for a long time), as well as correlations between the rate of increase and the rate of decrease of traits (traits that increase rapidly in popularity are also abandoned quickly and vice-versa). We also establish that alternative theories, that fashions result from individuals signaling their social status, or from individuals randomly copying each other, do not satisfactorily reproduce these empirical observations.

Video: R. Alex Bentley, Social Influence and Drift in Collective Behavior

Part of the Cultural Evolution Seminar Series at Brooklyn College

Download Video (500MB)

Abstract: Human decision models often begin with individual, cost-benefit analyses as the basic behavior, with any social influence as a secondary add-on. Thisoften underestimates social influence among humans, whose brains have actually evolved to handle social relations. In fact, a better starting point in many casesmay be to assume that people base their choices (consciously or not) primarily on the decisions of those around them. As captured by experiments and simpleevolutionary drift models, undirected social influence introduces an irrationality and unpredictability to collective behavior, with implications for anthropology,psychology and economics.

Alex Bentley is Reader in Anthropology at Durham University, where he is co-founder of the Centre for the Coevolution of Biologyand Culture, and Deputy Director of a 5 year project on ‘Tipping Points: Mathematics, Metaphors and Meanings”, funded by theLeverhulme Trust.

Catching Extra Time

Here I am on the Riva di Ca' di Dio in Venice visiting the 53rd International Art Exhibition. The black shirt and the tie entitle me to comment on the artworks with authority.

The shiny cube I'm leaning on is a showcase for Nikola Uzunovski's My Sunshine project. Nikola, an applied artist, wants to improve the quality of life at northern latitudes (or deep mountain valleys). The problem with these places is that, although they may well be wonderful in all other respects, they get light for a rather short time in winter. In the best of cases, lack of sunlight makes you a bit sleepy, in the worst case it makes you clinically depressed.

Nikola's solution is a device that lengthens the day: a mirror that floats up in the sky, electronically controlled to shine the sun's image on an otherwise dark spot on earth.

How does it work? Simply, the device exploits the fact that up in the sky the day lasts longer than at the earth's surface – as shown in the diagram at left (please do not blame Nikola for that). The mirror, floating inside a helium filled balloon, reflects 90% of the afternoon rays onto the earth below creating a virtual sun.

My sunshine is a step toward bringing Italian climate to Swedish civilization – the Eden of humanity. Bringing Swedish civilization to Italian climate, unfortunately, remains a daunting challenge for artists and scientists alike.