高清福利片

聽is lead author of the research published in the

The researchers from聽the University's and the newly created 聽looked at what drives the shape of our complex social networks. They believe the process underlying the formation of human social networks has largely been ignored in previous studies.

Dr Harre said: 鈥淲hat our research showed for the first time is that complex layers of social groups are formed by adding one more person to our 'friends' list. And much like the ripples in a pond after you throw in a stone, the strength of each connection diminishes or weakens as they expand out.

鈥淲e start with our life partners and best friends and extend to distant acquaintances. Each friend added is slightly more distant than those from the inner circles.

鈥淧reviously, thanks to British anthropologist and evolutionary psychologist Robin Dunbar,聽it was conjectured聽that our brains developed to the size they are to enable us to deal with the social complexity of other humans. We also knew that the size of our social groups are limited on average to a largest circle of around 130 -150 people.聽Our findings show that maintaining about five links, one for each social layer, is sufficient to support complex social networks of that size.鈥�

Dr Harre says that all of this becomes important when we consider the dynamic process of group formation.

鈥淲hen 鈥榮mall families鈥� of say four people join to form a larger 鈥榚xtended family鈥� of around 13-14 people,聽on average聽only one more connection per person聽is聽needed.聽

鈥淲hen 鈥榚xtended families鈥� merge into 鈥榗lans鈥� of say 40-45 people again only an average of one connection per person聽needs to be added. Finally, when 鈥榗lans鈥� combine to form the largest groups of 鈥榯ribes鈥� of approximately 130-150 people, again only one connection per person聽on average聽needs to be added.聽

鈥淭hese results show that it is聽sufficient聽to add an average of just one connection per person聽to increase the size of the group roughly three-fold at the next largest social layer.聽聽

鈥淗owever, beyond these group sizes our brains find managing the complex social interactions too聽difficult and聽it is easier for us to manage hierarchical organisational structures,鈥� Dr Harre said.

The researchers used data from two previous large scale studies to look at these two well-known models of social connectedness: the hierarchical dominance model which applies to corporations, military organisations and ape聽communities; and 鈥楨rd枚s-R茅nyi鈥櫬爊etworks that聽represent self-organising or grass roots communities聽similar聽to those of our聽hunter-gatherer forebears.