anthropogenic electromagnetic noise generated-.by humans in the <br />> frequency range up to five megahertz", Mouritsen says. The <br />> surprising thing here, the biologist adds, was that the intensity <br />> of the interference was far below the limits defined by the <br />> International Commission on Non-Ionizing Radiation Protection and <br />> the WHO. Considering the potential importance of the finding, <br />> Mouritsen and his team performed a large number of experiments to <br />> provide evidence of the effect they observed: ?Over the course of <br />> seven years we carried out numerous experiments and collected <br />> reliable evidence, in order to be absolutely certain that the <br />> effect actually exists.? Under the leadership of Svenja Engels, <br />> Mourtisen's doctorate students conducted numerous so-called <br />> double-blind studies. Several generations of students repeated <br />> the experiments independently of one another on the Oldenburg <br />> campus. What they found was that as soon the grounding of the <br />> screens was disconnected or electromagnetic broadband <br />> interference was deliberately created inside the aluminium-clad <br />> and earthed wooden huts, the birds' magnetic orientation ability <br />> was immediately lost again. <br />> Furthermore, the scientists were able to show that the disruptive <br />> effects were generated by electromagnetic fields that cover a <br />> much broader frequency range at a much lower intensity than <br />> previous studies had suggested. This electromagnetic broadband <br />> interference is omnipresent in urban environments. It is created <br />> wherever people use electronic devices. As expected, it is <br />> significantly weaker in rural areas. And indeed, unlike on the <br />> University campus, the magnetic compass of the robin did function <br />> in orientation cages placed one to two kilometres outside city <br />> limits, even without any screening. ?Thus, the effect of <br />> anthropogenic electromagnetic noise on bird migration is <br />> localised. However these findings should make us think ? both <br />> about the survival of migratory birds as well as about the <br />> potential effects for human beings, which have yet to be <br />> investigated?, Mouritsen concludes. <br />> PROFILE <br />> Prof. Dr. Henrik Mouritsen has been teaching and conducting <br />> research at the University of Oldenburg since 2002, and obtained <br />> his habilitation there in 2005. The Danish biologist has held a <br />> Lichtenberg Professorship from the VolkswagenStiftung since 2007. <br />> Through its ?Lichtenberg Professorships? initiative the <br />> foundation funds outstanding scientists in innovative fields of <br />> teaching and research. Mouritsen researches the behavioural, <br />> molecular, physiological and cognitive mechanisms underlying <br />> long-distance navigational abilities in migratory birds. As head <br />> of the international research group ?Neurosensorik/Animal <br />> Navigation? he has contributed substantially to the current state <br />> of the art suggesting that the birds use the Earth's magnetic <br />> field for orientation in two different ways. Light-sensitive <br />> molecules in their eyes enable them to visually detect the <br />> compass direction of the magnetic field. Furthermore, the birds <br />> seem to have magnetic sensors associated with the ophthal! <br />> mic branch of the trigeminal nerve, which are connected via <br />9 <br />