ing ▁and ▁s que aking ▁no ises . ▁Their ▁color ing ▁ranges ▁from ▁white ▁and ▁grey ▁to ▁black , ▁as ▁well ▁as ▁spe ck led ▁brown , ▁yellow , ▁and ▁orange . ▁According ▁to ▁Dr . ▁Leonard ▁Mc Co y ' s ▁dialog ue , ▁their ▁only ▁two ▁purposes ▁in ▁life ▁appear ▁to ▁be ▁to ▁eat ▁and ▁to ▁reproduce , ▁and ▁they ▁perform ▁both ▁of ▁these ▁functions ▁exception ally ▁well . ▁Mc Co y ▁con cludes ▁that ▁trib bles ▁use ▁over ▁ 5 0 % ▁of ▁their ▁met abol ism ▁for ▁reprodu ction ▁and ▁that ▁they ▁are ▁born ▁pre gn ant . ▁ ▁Due ▁to ▁their ▁t endency ▁to ▁over - pop ulate , ▁Star f le et ▁cons iders ▁trib bles ▁to ▁be ▁dangerous ▁organ isms ▁and ▁forb ids ▁their ▁transport ation . ▁ ▁A ▁creature ▁gen et ically ▁engine ered ▁to ▁h unt ▁trib bles ▁was ▁introduced ▁in ▁the ▁animated ▁episode ▁" More ▁Trib bles , ▁More ▁Tr ou bles " ▁( 1 9 7 3 ). ▁ ▁The ▁K ling ons , ▁in ▁whose ▁presence ▁trib bles ▁produce ▁a ▁conv uls ive , ▁sh rie king ▁reaction , ▁consider ▁them ▁" mort al ▁enemies ", ▁as ▁stated ▁in ▁the ▁Star ▁Tre k : ▁Deep ▁Space ▁N ine ▁episode ▁" Tri als ▁and ▁Trib ble - ations " ▁( 1 9 9 6 ). ▁ ▁The ▁Star ▁Tre k : ▁Short ▁Tre ks ▁episode ▁" The ▁Tr ouble ▁with ▁Edward " ▁reve als ▁that ▁trib bles ▁were ▁not ▁originally ▁" born