6、 9 toprinttheirmoney.SomeofthecurrenciesstudiedbyVriesekoopandhis 10 ,suchasthe Americandollar,weremadefromcotton.Othersweremadefrompolymers. The three 11 withthelowestnumbersofbacteriawereallprintedonpolymers.TheyincludedtheAustraliandollar
7、,theNewZealanddollarandsomeMexicanpesos.Theothercurrencieswereprintedonfabricmade 12 of cotton.Fewergermslivedonthepolymernotes.Thisconnectionsuggeststhat 13 haveahardertimestayingaliveonpolymersurfaces.Scientistsneedtodomorestudiestounderstandhowgermsliv