Brightness discrimination in the South African fur seal (Arctocephalus pusillus)
Brightness discrimination in the South African fur seal (Arctocephalus pusillus)
复制标题
南非海狗 (Arctocephalus pusillus) 的亮度辨别
DOI：
10.1016/j.visres.2013.03.003
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发表时间：
2013
期刊：
影响因子：
1.8
通讯作者：
Dehnhardt G.
中科院分区：
文献类型：
--
作者：
Scholtyssek C. ;Dehnhardt G.
在水下，目标与背景之间的对比度随着目标与观察者距离的增加而减小，远大于空气中的对比度。因此，对于海洋捕食者，如鳍脚类动物，拥有对亮度差异的高敏感度将是有利的，因为这将增加肉眼可以发现猎物的距离。很少有研究研究管脚类的亮度辨别阈值。两项关于海豹的研究证实，鳍脚类动物的亮度辨别阈值较低，而南非毛海豹的亮度辨别阈值似乎是海豹的两倍。然而，对南非毛海豹的实验是在不充分的条件下进行的，这可能导致对该物种的亮度辨别能力的低估。手头的这项研究重新调查了南非毛海豹在控制良好的条件下的亮度辨别阈值。在两个选择的强制选择任务中，一只海豹被训练来指示显示器上黑色背景上呈现的两个灰色圆盘中较亮的一个的位置。确定了11个标准强度的阈值，每个标准强度与8个较低的比较强度进行了测试。研究发现，毛海豹能够感知到8-10%的亮度差异，这一点好于目前所测试的含磷物种。然而，对于低标准强度，阈值增加，这可能是由于毛海豹的暗适应速度相对较慢。这些结果是根据在觅食潜水过程中裙脚类动物视觉信息的相关性进行讨论的，并与在先前研究中在与毛海豹相同的条件下进行测试的港海豹的结果进行了直接比较。
Underwater, the contrast between object and background is much larger reduced with increasing distance between object and observer than in air. For marine predators, such as pinnipeds, it would therefore be advantageous to possess a high sensitivity for brightness differences, since this would increase the distance at which prey can be detected visually. Few studies have examined the brightness discrimination thresholds of pinnipeds. Two studies with phocid seals have confirmed low brightness discrimination thresholds in pinnipeds whereas the threshold obtained for the South African fur seal seems to be twice as high as that of the phocids. However, the experiments with the South African fur seal have been conducted under inadequate conditions which likely resulted in an underestimation of the brightness discrimination ability of this species. The study at hand reinvestigated the brightness discrimination threshold of the South African fur seal under well controlled conditions. In a two alternative forced choice task, one fur seal was trained to indicate the position of the brighter of two gray discs presented on a black background on a monitor. The thresholds were determined for 11 standard intensities each tested against 8 lower comparison intensities. It was found that the fur seal was able to perceive brightness differences of 8–10%, which is better than the phocid species tested so far. For low standard intensities, however, the threshold increased which could to be due to a relative slow dark adaptation rate of the fur seal. The results are discussed in terms of the relevance of visual information for pinnipeds during foraging dives and are directly compared to the results obtained for the harbor seal which has been tested under the same conditions as the fur seal in a previous study.
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影响因子：
64.8
作者：
R. Schusterman;R. Balliet
通讯作者：
R. Balliet
脊椎动物的眼睛及其自适应辐射。
影响因子：
22.4
作者：
M. Zigler
通讯作者：
M. Zigler
影响因子：
1.8
作者：
Weiffen, Michael;Moeller, Bettina;Dehnhardt, Guido
通讯作者：
Dehnhardt, Guido
作用位置：韦伯分数作为低频声压的函数。
DOI：
10.1121/1.407370
发表时间：
1993
期刊：
The Journal of the Acoustical Society of America
影响因子：
--
作者：
L. M. Ward;Kelly P. Davidson
通讯作者：
Kelly P. Davidson
白令海斑海豹 Phoca largha 的颜色辨别
影响因子：
1.8
作者：
Douglas Wartzok;M. G. McCormick
通讯作者：
M. G. McCormick