Passive electroreception in bottlenose dolphins Tursiops truncatus: implication for micro- and large-scale orientation
Data files
Jul 26, 2023 version files 324.70 MB
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1_Donna_correct_go_nogo_trial_22.03.2019.mp4
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2_Donna_correct_response_electric_stimulus_5µVcm_22.03.19.mp4
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DollyAC.xlsx
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DollyDonnaDC.xlsx
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DonnaAC.xlsx
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README.md
Abstract
For the two dolphin species Sotalia guianensis and Tursiops truncatus, it was shown that the vibrissal crypts located on the rostrum represent highly innervated, ampullary electroreceptors and that both species are correspondingly sensitive to weak electric fields. For a comparative assessment of the sensitivity of the bottlenose dolphin's electroreceptive system, we determined detection thresholds for DC and AC electric fields with two bottlenose dolphins. In a psychophysical experiment, the animals were trained to respond to electric field stimuli using the go/no-go paradigm. We show that bottlenose dolphins are able to detect DC electric fields as low as 2.4 &[mu]V cm -1 and 5.5 &[mu]V cm -1, respectively, a detection threshold in the same order of magnitude as those in the platypus and the Guiana dolphin. Detection thresholds for AC fields (1, 5, and 25 Hz) were generally higher than those for DC fields, and the sensitivity for AC fields decreased with increasing frequency. Although the electroreceptive sensitivity of dolphins is lower than that of elasmobranchs, it is suggested that it allows orientation at micro and large scales. In dolphins pursuing benthic foraging strategies, electroreception may facilitate short-range prey detection and target-oriented snapping of their prey. Furthermore, we discuss that the ability to detect weak electric fields may enable dolphins to detect the Earth's magnetic field through induction-based magnetoreception, thus allowing large-scale orientation.
Usage notes
Description
Data of the paper at JEB.
The files contain experimental data for both animals testing their abilities to detect DC and AC electric fields in water and videos.
After a preliminary study (Hüttner et al., 2022) demonstrated passive electroreception in bottlenose dolphins, the present study aimed to evaluate the sensitivity of bottlenose dolphins to weak electric fields in water (DC and low-frequency AC stimuli).
The present data show that the two dolphins learned to reliably respond to electric field stimuli that could benefit them during prey detection or large-scale orientation using induction-based magnetoreception.
Dataset includes:
Performances are shown in percent (%). Electric field strength was reduced if the dolphin's performance (hit rate) remained > 80 % hits over at least 30 trials of this electric field strength.
1) Performance of dolphins Donna and Dolly during DC detection tests including
- Performance (hit rate) over last 30 trials for each tested electric field strength (500 µV cm-1 - 2 µV cm-1)
- false alarm rate during these sessions
- performance of all electric field trials of each tested electric field strength
- overall performance (correct responses on all go & no-go trials)
2) Performance of dolphin Donna during AC detection tests including
- Performance (hit rate) over last 30 trials for each tested electric field strength for each tested AC frequency (1 Hz, 5 Hz, and 25 Hz)
- false alarm rate during these sessions
- performance of all electric field trials of each tested electric field strength
- overall performance (correct responses on all go & no-go trials)
3) Performance of dolphin Dolly during AC detection tests
- Performance (hit rate) over last 30 trials for each tested electric field strength for each tested AC frequency (1 Hz and 5 Hz)
- false alarm rate during these sessions
- performance of all electric field trials of each tested electric field strength
- overall performance (correct responses on all go & no-go trials)
Videos include:
- Example video of a no-go trial: Donna showing a correct response on a no-go trial (correct rejection). After Donna enters the apparatus and stations correctly on the target and the resting platform she remains calmly inside the apparatus for a predefined of 12 s. The experimenter (TH) then gives a short whistle sound (secondary reinforcement, not audible) and Donna leaves the apparatus and receives a fish reward from the trainer sitting on the other side of the poll (not visible).
- Example of a go trial with electric field stimulus: Donna correctly responding to an electric stimulus-present trial with an electric field strength of 5 µV cm-1. After the station correctly inside the apparatus, the experimenter (TH) presents the electric stimulus. Within 5 s after the stimulus onset, Donna leaves the station and exits the apparatus. This so-called hit was also secondarily reinforced with a short whistle sound by the experimenter followed by a fish reward from the trainer.