Investigations carried out in the 1950s on the use of polarized light by sandhoppers as a compass reference did not reach convincing results. Therefore, polarized light compass orientation in the sandhopper Talitrus saltator seems to be a traditional attribute more than a solid demonstration. Our tests carried out under artificial and natural conditions of illumination using different polarizing and neutral density (grey) filters demonstrated that T. saltator perceives polarized light; however, it does not use the skylight polarized light as a cue for menotactic orientation. However, since the sky spectral and luminance gradients were not completely eliminated in our tests, a possible influence of these two celestial factors of orientation could still be present. Therefore, we conclude that this species, in this experimental paradigm at least, does not use a polarized light compass mechanism, despite a very good sun compass system of orientation. (C) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
Do sandhoppers use the skylight polarization as a compass cue?
Mercatelli Luca
2013
Abstract
Investigations carried out in the 1950s on the use of polarized light by sandhoppers as a compass reference did not reach convincing results. Therefore, polarized light compass orientation in the sandhopper Talitrus saltator seems to be a traditional attribute more than a solid demonstration. Our tests carried out under artificial and natural conditions of illumination using different polarizing and neutral density (grey) filters demonstrated that T. saltator perceives polarized light; however, it does not use the skylight polarized light as a cue for menotactic orientation. However, since the sky spectral and luminance gradients were not completely eliminated in our tests, a possible influence of these two celestial factors of orientation could still be present. Therefore, we conclude that this species, in this experimental paradigm at least, does not use a polarized light compass mechanism, despite a very good sun compass system of orientation. (C) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.