they livive highn ththe tr-tops, and are one of the mtt endadanger primamateon the planet.. rosamira: cotton-top tamarins are ononly found here in colbib. and onlyly in one partrticulart of the c caribbean regegion. in the 1960's and 1970'shehey were used en masseor aninima experimentnts, for studidies on bowel cancncer. back then, 20,000 to 30,000 of them w were exported to the u.. reporter: today, therere only arou 700000 coon-top tamarins still liliving in the e wil. rosamira g guillen used d to a zoo director, but then she sacrificiced her career r to p protect ththe species. today y she runs thehe fundacn proyecto tititi. itits biggest spsponsor is nonoe her than movie and media giant diey.. rorosamira: our r focus is maian researchining and protececting cotton-t-top tamarins.s. but t right now, t the most importrtant factor i is that wee to preserve ththe rainforestsi order to save thmonkeys.s. reporter: the rainforest here in northern colombia is comprised of an array of smaller forest areas. much of the region has already been deforested. the ngo aims to link up the i