Adding an extra entrance to an ants' nest reduces their foraging efficiency: more ants go foraging, but they are less able to find and distinguish between food sources of varying value.
Funding: M.L. was supported by a Belgian PhD Grant from the F.R.I.A. (Fonds pour la formation à la Recherche dans l'Industrie et dans l'Agriculture). C.D. is Research Director from the Belgian National Fund for Scientific Research (FRS-F.N.R.S). This paper was published with the Financial support of the "Fondation Universitaire de Belgique " and of the grant N°CDR J.0053.18F from FRS-FNRS. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interests: The authors have declared that no competing interests exist.