icing ▁their ▁support ▁for ▁the ▁project . ▁The ▁authors ▁write ▁that ▁human ▁be ings ▁are ▁intellig ent ▁animals ▁with ▁a ▁varied ▁social , ▁emot ional , ▁and ▁cogn itive ▁life . ▁If ▁great ▁ap es ▁also ▁display ▁such ▁attributes , ▁the ▁authors ▁argue , ▁they ▁des erve ▁the ▁same ▁consideration ▁humans ▁extend ▁to ▁members ▁of ▁their ▁own ▁species . ▁ ▁The ▁book ▁highlight s ▁find ings ▁that ▁support ▁the ▁capacity ▁of ▁great ▁ap es ▁to ▁possess ▁rational ity ▁and ▁self - cons cious ness , ▁and ▁the ▁ability ▁to ▁be ▁aware ▁of ▁themselves ▁as ▁distinct ▁entities ▁with ▁a ▁past ▁and ▁future . ▁Document ed ▁convers ations ▁( in ▁sign ▁languages ) ▁with ▁individual ▁great ▁ap es ▁are ▁the ▁basis ▁for ▁these ▁find ings . ▁Other ▁subjects ▁addressed ▁within ▁the ▁book ▁include ▁the ▁division ▁placed ▁between ▁humans ▁and ▁great ▁ap es , ▁great ▁ap es ▁as ▁persons , ▁progress ▁in ▁gain ing ▁rights ▁for ▁the ▁sever ely ▁intellect ually ▁disabled ▁( once ▁an ▁over look ed ▁minor ity ), ▁and ▁the ▁situation ▁of ▁great ▁ap es ▁in ▁the ▁world ▁today . ▁ ▁Their ▁bi ological ▁similarity ▁with ▁humans ▁is ▁also ▁key ▁to ▁the ▁tra its ▁for ▁which ▁they ▁are ▁valuable ▁as ▁research ▁subjects . ▁For ▁example , ▁testing ▁of ▁mon oc l onal ▁ant ib ody ▁treat ments ▁cannot ▁be ▁done ▁in ▁species ▁less ▁similar ▁to ▁humans ▁than ▁ch imp anze es . ▁Because ▁the ▁ant ib od ies ▁do ▁not ▁el ic it ▁imm une ▁responses ▁in ▁ch imp anze es , ▁they