ing ▁expression ▁seen ▁in ▁fr ustration ▁or ▁after ▁defeat ). ▁The ▁ch imp anze es ▁correctly ▁matched ▁the ▁cli ps ▁to ▁the ▁fa cial ▁expressions ▁that ▁shared ▁their ▁meaning , ▁demonstr ating ▁that ▁they ▁understand ▁the ▁emot ional ▁significance ▁of ▁their ▁fa cial ▁expressions . ▁Me asures ▁of ▁peri pher al ▁skin ▁temperature ▁also ▁indicated ▁that ▁the ▁video ▁cli ps ▁em otion ally ▁affected ▁the ▁ch imp anze es . ▁ ▁Rod ents ▁In ▁ 1 9 9 8 , ▁Ja ak ▁P ank se pp ▁proposed ▁that ▁all ▁m amm al ian ▁species ▁are ▁equ ipped ▁with ▁bra ins ▁capable ▁of ▁generating ▁emot ional ▁experiences . ▁Sub sequ ent ▁work ▁exam ined ▁studies ▁on ▁rod ents ▁to ▁provide ▁found ational ▁support ▁for ▁this ▁claim . ▁One ▁of ▁these ▁studies ▁exam ined ▁whether ▁r ats ▁would ▁work ▁to ▁alle vi ate ▁the ▁dist ress ▁of ▁a ▁cons pec ific . ▁R ats ▁were ▁trained ▁to ▁press ▁a ▁lever ▁to ▁avoid ▁the ▁delivery ▁of ▁an ▁electric ▁shock , ▁sign aled ▁by ▁a ▁visual ▁c ue , ▁to ▁a ▁cons pec ific . ▁They ▁were ▁then ▁tested ▁in ▁a ▁situation ▁in ▁which ▁either ▁a ▁cons pec ific ▁or ▁a ▁St y ro fo am ▁block ▁was ▁ho isted ▁into ▁the ▁air ▁and ▁could ▁be ▁lower ed ▁by ▁pressing ▁a ▁lever . ▁R ats ▁that ▁had ▁previous ▁experience ▁with ▁cons pec ific ▁dist ress ▁demonstrated ▁greater ▁than ▁ten - fold ▁more ▁responses ▁to ▁lower ▁a ▁dist ress ed ▁cons pec ific ▁compared ▁to ▁r ats ▁in