. ▁One ▁behaviour ▁associated ▁with ▁fear ▁in ▁r ats ▁is ▁free zing . ▁If ▁female ▁r ats ▁experience ▁electric ▁shock s ▁to ▁the ▁feet ▁and ▁then ▁witness ▁another ▁rat ▁experien cing ▁similar ▁foot sh ock s , ▁they ▁free ze ▁more ▁than ▁females ▁without ▁any ▁experience ▁of ▁the ▁shock s . ▁ ▁This ▁suggests ▁em path y ▁in ▁experienced ▁r ats ▁witness ing ▁another ▁individual ▁being ▁shock ed . ▁ ▁Furthermore , ▁the ▁demonstr ator ' s ▁behaviour ▁was ▁changed ▁by ▁the ▁behaviour ▁of ▁the ▁witness ; ▁demonstr ators ▁fro ze ▁more ▁following ▁foot sh ock s ▁if ▁their ▁witness ▁fro ze ▁more ▁creating ▁an ▁em path y ▁loop . ▁ ▁Several ▁studies ▁have ▁also ▁shown ▁rod ents ▁can ▁respond ▁to ▁a ▁condition ed ▁stim ulus ▁that ▁has ▁been ▁associated ▁with ▁the ▁dist ress ▁of ▁a ▁cons pec ific , ▁as ▁if ▁it ▁were ▁pa ired ▁with ▁the ▁direct ▁experience ▁of ▁an ▁un condition ed ▁stim ulus . ▁These ▁studies ▁suggest ▁that ▁rod ents ▁are ▁capable ▁of ▁shared ▁affect , ▁a ▁concept ▁critical ▁to ▁em path y . ▁ ▁H ors es ▁Although ▁not ▁direct ▁evidence ▁that ▁horses ▁experience ▁emot ions , ▁a ▁ 2 0 1 6 ▁study ▁showed ▁that ▁domestic ▁horses ▁react ▁differently ▁to ▁seeing ▁photograph s ▁of ▁positive ▁( h appy ) ▁or ▁negative ▁( ang ry ) ▁human ▁fa cial ▁expressions . ▁ ▁When ▁view ing ▁angry ▁faces , ▁horses ▁look ▁more ▁with ▁their ▁left ▁eye ▁which ▁is ▁associated ▁with ▁perce iving ▁negative ▁stim uli . ▁Their ▁heart ▁rate