Sumner-Rooney L.H.,Queens University Marine Laboratory |
Sumner-Rooney L.H.,Queen's University of Belfast |
Murray J.A.,California Polytechnic State University, San Luis Obispo |
Cain S.D.,Eastern Oregon University |
And 2 more authors.
Journal of Natural History | Year: 2014
Several animals and microbes have been shown to be sensitive to magnetic fields, though the exact mechanisms of this ability remain unclear in many animals. Chitons are marine molluscs which have high levels of biomineralised magnetite coating their radulae. This discovery led to persistent anecdotal suggestions that they too may be able to navigationally respond to magnetic fields. Several researchers have attempted to test this, but to date there have been no large-scale controlled empirical trials. In the current study, four chiton species (Katharina tunicata, Mopalia kennerleyi, Mopalia muscosa and Leptochiton rugatus, n = 24 in each) were subjected to natural and artificially rotated magnetic fields while their movement through an arena was recorded over four hours. Field orientation did not influence the position of the chitons at the end of trials, possibly as a result of the primacy of other sensory cues (i.e. thigmotaxis). Under non-rotated magnetic field conditions, the orientation of subjects when they first reached the edge of an arena was clustered around 309–345° (north–north-west) in all four species. However, orientations were random under the rotated magnetic field, which may indicate a disruptive effect of field rotation. This pattern suggests that chitons can detect and respond to magnetism. © 2014, © 2014 Taylor & Francis.
Kunc H.P.,Queen's University of Belfast |
Kunc H.P.,Queens University Marine Laboratory |
Lyons G.N.,Queen's University of Belfast |
Lyons G.N.,Queens University Marine Laboratory |
And 6 more authors.
American Naturalist | Year: 2014
Many species are currently experiencing anthropogenically driven environmental changes. Among these changes, increasing noise levels are specifically a problem for species using acoustic signals (i.e., species relying on signals that use the same sensory modality as anthropogenic noise). Yet many species use other sensory modalities, such as visual and olfactory signals, to communicate. However, we have only little understanding of whether changes in the acoustic environment affect species that use sensory modalities other than acoustic signals. We studied the impact of anthropogenic noise on the common cuttlefish Sepia officinalis, which uses highly complex visual signals.We showed that cuttlefish adjusted their visual displays by changing their color more frequently during a playback of anthropogenic noise, compared with before and after the playback. Our results provide experimental evidence that anthropogenic noise has a marked effect on the behavior of species that are not reliant on acoustic communication. Thus, interference in one sensory channel, in this case the acoustic one, affects signaling in other sensory channels. By considering sensory channels in isolation, we risk overlooking the broader implications of environmental changes for the behavior of animals. © 2014 by The University of Chicago. All rights reserved.