“…Consistent with these findings, a number of studies have shown that people tend to behave in a more generous and pro-social manner when they are being observed by others. This tendency occurs not only in adults ( Bereczkei et al, 2007 ; Iredale et al, 2008 ; Izuma et al, 2010 ; Van Vugt and Iredale, 2013 ) but also in children ( Engelmann et al, 2012 , 2013 ; Houser et al, 2012 ; Leimgruber et al, 2012 ; Fujii et al, 2015 ). The tendency for people to behave in a more pro-social manner when they are observed by others, and thus may accrue reputation, is so strong that it can be elicited even by subtle cues of monitoring such as pictures of eyes ( Haley and Fessler, 2005 ; Bateson et al, 2006 ; Mifune et al, 2010 ; Keller and Pfattheicher, 2011 ; Oda et al, 2011 ; Ekström, 2012 ; Nettle et al, 2013 ) and even three dots in a “watching eyes” configuration ( Rigdon et al, 2009 ).…”