Have you ever arrived somewhere and wondered how you got there? Scientists at the University of Leeds believe they may have found the answer.
Their research suggests that humans flock like sheep and birds, subconsciously following a minority of individuals. The study at the University of Leeds shows that it takes a minority of just five per cent to influence a crowd's direction - and that the other 95 per cent follow without realising it.
The findings could have major implications for directing the flow of large crowds, in particular in disaster scenarios, where verbal communication may be difficult. "There are many situations where this information could be used to good effect," says Professor Jens Krause of the University's Faculty of Biological Sciences. "At one extreme, it could be used to inform emergency planning strategies and at the other, it could be useful in organising pedestrian flow in busy areas."
Professor Krause, with PhD student John Dyer, conducted a series of experiments where groups of people were asked to walk randomly around a large hall. Within the group, a select few received more detailed information about where to walk. Participants were not allowed to communicate with one another but had to stay within arms length of another person.
The findings show that in all cases, the 'informed individuals' were followed by others in the crowd, forming a self-organising, snake-like structure. "We've all been in situations where we get swept along by the crowd," says Professor Krause. "But what's interesting about this research is that our participants ended up making a consensus decision despite the fact that they weren't allowed to talk or gesture to one another. In most cases the participants didn't realise they were being led by others."
Other experiments in the study used groups of different sizes, with different ratios of 'informed individuals'. The research findings show that as the number of people in a crowd increases, the number of informed individuals decreases. In large crowds of 200 or more, five per cent of the group is enough to influence the direction in which it travels. The research also looked at different scenarios for the location of the 'informed individuals' to determine whether where they were located had a bearing on the time it took for the crowd to follow.
"We initially started looking at consensus decision making in humans because we were interested in animal migration, particularly birds, where it can be difficult to identify the leaders of a flock," says Professor Krause. "But it just goes to show that there are strong parallels between animal grouping behaviour and human crowds."
This research was funded by the Engineering and Physical Sciences Research Council and was a collaborative study involving the Universities of Oxford and Wales Bangor. The paper relating to this research, entitled Consensus decision making in human crowds is published in the current issue of Animal Behaviour Journal.
Notes to editors:
1. Jens Krause is Professor of Behavioural Ecology, in the Institute of Integrative and Comparative Biology. His research interests focus on the mechanisms and functions of group-living in animals.
2. The Faculty of Biological Sciences at the University of Leeds is one of the largest in the UK, with over150 academic staff and over 400 postdoctoral fellows and postgraduate students. The Faculty has been awarded research grants totalling some £60M and funders include charities, research councils, the European Union and industry. Each of the major units in the Faculty has the highest Grade 5 rated research according to the last government (HEFCE) Research Assessment Exercise, denoting research of international standing. The Faculty is also consistently within the top three for funding from the government's research councils, the BBSRC and NERC. http://www.fbs.leeds.ac.uk/
3. The University of Leeds is one of the largest higher education institutions in the UK with more than 30,000 students from 130 countries. With a total annual income of £422m, Leeds is one of the top ten research universities in the UK, and a member of the Russell Group of research-intensive universities. It was recently placed 80th in the Times Higher Educational Supplement's world universities league table and the University's vision is to secure a place among the world's top 50 by 2015.
4. The Engineering and Physical Sciences Research Council (EPSRC) is the UK's main agency for funding research in engineering and the physical sciences. EPSRC invests more than £500 million a year in research and postgraduate training to help the nation handle the next generation of technological change. The areas covered range from information technology to structural engineering, and from mathematics to materials science. This research forms the basis for future economic development in the UK and improvements in everyone's health, lifestyle and culture. For more information visit www.epsrc.ac.uk/