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Assessing the impact of human development on animals is complicated by the fact that overt effects may have covert causes. Cryptic impacts (sensuRaiter et al. 2014) can arise where sensory stimuli to which species respond fall outside the human sensory range. Ultraviolet (UV) light, which is detected by a range of nonprimate mammals, is a potential example. We review evidence that dark‐adapted eyes of reindeer–caribou Rangifer taranduscan detect light at 330–410 nm emitted by electrical corona on high‐voltage power lines, which is necessarily barely visible to humans. Based on this, we suggest that the superior ability of Rangiferto detect corona UV light may partly account for the tendency of the animals to avoid power lines. Rangiferhas UV‐permissive ocular media that transmit approximately 15 times more corona light than human eyes. Retinal irradiance under full dilation is in the order of 7 times greater in Rangifercompared with humans. Seasonal transformation of the tapetum lucidum substantially increases retinal sensitivity in this species in winter. Threshold distances of detection of corona by Rangiferare in the order of hundreds of meters. Displays of corona may catch the animals' attention, and plume coronas, in particular, may induce the illusion of motion (the phi phenomenon), thereby falsely signaling the presence of potential predators. Both features are likely to increase wariness and cause animals to withdraw from the source of the stimulus. We suggest that spatial and temporal variability of corona contributes to substantial variation observed in the strength and persistence of avoidance responses in Rangiferat these structures. © 2016 The Authors. Wildlife Society Bulletinpublished by Wiley Periodicals, Inc. on behalf of The Wildlife Society.

Arguments in physics regarding light are often based on either mechanistic concepts, or on a "which way" discussion where the question of "indistinguishability" is crucial. The last kind of arguing is based on the concept of an indivisible, point-like photon, a concept stemming historically from the most common explanation of the photoelectric effect. There seems, however, to be an important lack of consistency between arguing based on indivisible particle-like photons and the actual quantum formalism for calculating detailed outcomes from various experiments. Crucial parts of the actual calculations of diffraction and interference phenomena seem in fact to be very similar in the classical and the quantum descriptions, and are based either on classic electromagnetic fields, or on quantum fields. It is the interpretationsthat differ. It would be interesting to downgrade the concept of an indivisible particle-like photon and upgrade the importance of the quantum field description we reallyuse in the detailed calculations. It is our impression that we by that could avoid quite a few weird conclusions we live with today. A few examples are given.

In 1992 Anthony Hopwood introduced a hypothesis that electric and magnetic fields close to high voltage power lines might focus electrically charged particles in cosmic radiation so that people living close by would be exposed to higher doses of ionising radiation than if the power line was not present. This hypothesis has been tested using thermoluminescent dosemeters as detectors, which are free from electric noise artifacts that might influence Geiger - Müller detectors. Detectors were placed on snow covered cultivated land at low altitudes as well as on an ice covered lake in a mountain area to reduce background radiation from the ground. In neither case could a focusing effect be demonstrated.

Exposure to electromagnetic fields may cause breast cancer in women if it increases susceptibility to sex-hormone-related cancer by diminishing the pineal gland's production of melatonin. We have studied breast cancer incidence in female radio and telegraph operators with potential exposure to light at night, radio frequency (405 kHz-25 MHz), and, to some extent, extremely low frequency fields (50 Hz). We linked the Norwegian Telecom cohort of female radio and telegraph operators working at sea to the Cancer Registry of Norway to study incident cases of breast cancer. The cohort consisted of 2,619 women who were certified to work as radio and telegraph operators between 1920 and 1980. Cancer incidence was analyzed on the basis of the standardized incidence ratio (SIR), with the Norwegian female population as the comparison group. The incidence of all cancers was close to unity (SIR=1.2). An excess risk was seen for breast cancer (SIR=1.5). Analysis of a nested case-control study within the cohort showed an association between breast cancer in women aged 50 + years and shift work. In a model with adjustment for age, calendar year, and year of first birth, the rate ratio for breast cancer associated with being a radio and telegraph operator-in comparison with all Norwegian women born 1935 or later-analyzed with Poisson regression, was 1.5 after adjustment for fertility factors. These results support a possible association between work as a radio and telegraph operator and breast cancer. Future epidemiologic studies on breast cancer in women aged 50 and over, should address possible disturbances of chronobiological parameters by environmental factors.