Streetwise urban ants from New York have developed a taste for the kind of diet frequently chosen by their human neighbours . Tests on insects collected from pavements and traffic islands in Manhattan show that their bodies contain the molecular fingerprint of junk food . The same was not true of more genteel ants that frequent leafy park areas . The scientists tested more than 100 ants representing 21 species from dozens of sites in the Big Apple . Lead researcher Dr Clint Penick , from North Carolina State University , said : 'Human foods clearly make up a significant portion of the diet in urban species . These are ants eating our garbage , and this may explain why pavement ants are able to achieve such large populations in cities . ' The scientists tested more than 100 ants representing 21 species from dozens of sites in the Big Apple . Their diet was assessed by analysing the kind of carbon in their bodies . All animals , including humans , take in carbon from food , but the atomic 'strain ' of the element found in the ants was specifically associated with corn and sugar cane . Corn and refined sugar are both abundant in human processed foods where they are used as sweeteners and flavour enhancers . Evidence of the signature carbon-13 isotope indicated that the ants had adopted a junk food diet . The species with the highest levels of carbon-13 was the most common ant on the street , the 'pavement ant ' Tetramorium caespitum . Like members of inner city gangs , Tetramorium soldiers engage in violent turf wars as rival colonies fight for territory . They also do a lot of breaking and entering of people 's homes , and are a recognised house pest . Tests on insects collected from pavements and traffic islands in Manhattan show that their bodies contain the molecular fingerprint of junk food . The scientists , whose findings are reported in the journal Proceedings of the Royal Society B , discovered one street-living ant that turned its antennae up at human food . Lasius emarginatus , only identified in New York City in the past five years , was also found in high numbers on Manhattan 's pavements and traffic islands . But the isotope analysis showed no evidence of a human-like diet . Instead , the ant appeared to divide its time between subterranean nests and foraging in the branches of city trees . 'This highlights the complex nature of urban ecosystems and how much we still have to learn about how these species relate to each other and to the environment , ' said Dr Penick . 'We wanted to learn more about why some ant species are able to live alongside us , on sidewalks or in buildings , while other species stay on the outskirts of human development , '' says Dr Penick , . `` This could also help us determine which species are doing the most to clean up our trash . '' Read more at : .
Insects were collected from pavements and traffic islands in Manhattan . Bodies contain the molecular fingerprint of junk food . Element found in the ants associated with corn and sugar cane .