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  • Print publication year: 2016
  • Online publication date: May 2016

7 - Playing lemurs: why primates have been playing for a long time

from Part III - Why lemurs keep in touch


We do not stop playing because we get old. We get old because we stop playing

Stanley G. Hall, 1904

Playing, an everyday life activity: easy to spot, hard to define

After focusing for a long time on animal grief, trauma, violence, pain and suffering, comparative psychologists have been lately putting their efforts into dealing with happiness, laughter, joy and affection both in humans and other animals (the so-called ‘positive psychology’). Most of the ‘positive emotions’ which are under the psychologists’ magnifying glass are also indissolubly linked to play. Every day of our lives is punctuated by play and humour. We play during conversation with friends on the phone or on Skype, or when we post messages on Facebook – frequently inserting a smiling face like this :-) – etc. We play with our conspecifics and also with members of other species. Dogs, cats and even rats can be wonderful playmates. We play because it is pleasurable and rewarding. By social play and humour we experience emotions that can pass individuals’ boundaries and create a network of social and affective bonds (Power, 2000). Despite its pervasive nature, play is one of the most mysterious behaviours an ethologist can come across.

The difficulty with studying play behaviour starts with its theoretical definition. In his Confessions (Book 11, Chapter 14), St Augustine pondered the meaning of time, ‘Quid ergo est tempus? Si nemo ex me quaerit, scio: si quaerenti explicare velim, nescio’ [What is time? If no one asks me, I know. If I want to explain it, I no longer know]. Maybe the frustration experienced by St Augustine is the same as that experienced by most ethologists when dealing with the definition of play (Palagi and Paoli, 2007, 2008). We have no problems in recognising a playful interaction of our dogs, cats and children; however, as we go through the extensive literature dedicated to play we soon realise that there are as many definitions of play as there are the authors who studied it (for an extensive review see Burghardt, 2005). Play has been often defined via litotes, by not specifying what it is but by specifying what it is not. As play lacks certain characteristics that are typical of the serious and functional behaviours, play has been defined as a non-functional behaviour with no obvious immediate benefits (Martin and Caro, 1985; Bekoff and Allen, 1998).

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