School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK
School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK.
J Exp Biol. 2018 Jul 4;221(Pt 13):jeb173831. doi: 10.1242/jeb.173831.
Animals can make use of camouflage to reduce the likelihood of visual detection or recognition and thus improve their chances of survival. Background matching, where body colouration is closely matched to the surrounding substrate, is one form of camouflage. Hermit crabs have the opportunity to choose their camouflage independently of body colouration as they inhabit empty gastropod shells, making them ideal to study their choice of camouflage. We used 3D-printed artificial shells of varying contrasts against a grey substrate to test whether hermit crabs prefer shells that they perceive as less conspicuous. Contrast-minimising shells were chosen for Weber contrasts stronger than -0.5. However, in looming experiments, animals responded to contrasts as weak as -0.2, indicating that while they can detect differences between shells and the background, they are only motivated to move into those shells when the alternatives contrast strongly. This suggests a trade-off between camouflage and vulnerability introduced by switching shells.
动物可以利用伪装来降低被视觉发现或识别的可能性，从而提高它们的生存机会。背景匹配是伪装的一种形式，即身体颜色与周围的基质非常匹配。寄居蟹有机会独立于体色选择它们的伪装，因为它们栖息在空的腹足纲贝壳中，这使它们成为研究伪装选择的理想选择。我们使用了与灰色基质形成不同对比度的 3D 打印人工贝壳来测试寄居蟹是否更喜欢它们认为不那么显眼的贝壳。韦伯对比度大于-0.5 的贝壳被选择为最小化对比度。然而，在逼近实验中，动物对弱至-0.2 的对比度做出反应，这表明尽管它们可以检测到贝壳和背景之间的差异，但只有当替代物对比度很强时，它们才会有动力进入那些贝壳。这表明，通过更换贝壳，伪装和脆弱性之间存在权衡。
