(PhysOrg.com) -- In 1913 Theodore Roosevelt added cartographer to his resume when he and his crew ventured up an unspeakably dangerous and uncharted tributary named the River of Doubt. Now, on a charting expedition of their own, Rockefeller University scientists have completed a journey that has also defied expectation. In work to be published in the January 9 issue of Cell, the team reports the discovery of a new family of receptors in the fly nose, a finding that not only fills in a missing piece in the organizational logic of the insect olfactory system but also unearths one of the most ancient mechanisms that organisms have evolved to smell.