Palavalli-Nettimi Ravindra, Narendra Ajay
Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia
Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia.
J Exp Biol. 2018 Apr 6;221(Pt 7):jeb177238. doi: 10.1242/jeb.177238.
Evolution of a smaller body size in a given lineage, called miniaturisation, is commonly observed in many animals including ants. It affects various morphological features and is hypothesised to result in inferior behavioural capabilities, possibly owing to smaller sensory organs. To test this hypothesis, we studied whether reduced spatial resolution of compound eyes influences obstacle detection or obstacle avoidance in five different species of ants. We trained all ant species to travel to a sugar feeder. During their return journeys, we placed an obstacle close to the nest entrance. We found that ants with higher spatial resolution exited the corridor - the area between the two ends of the obstacle - on average 10 cm earlier, suggesting they detected the obstacle earlier in their path. Ants with the lowest spatial resolution changed their viewing directions only when they were close to the obstacle. We discuss the effects of miniaturisation on visual navigational competence in ants.
在特定谱系中体型变小的进化过程，即所谓的小型化，在包括蚂蚁在内的许多动物中普遍可见。它会影响各种形态特征，据推测可能会导致行为能力下降，这可能是由于感觉器官较小所致。为了验证这一假设，我们研究了复眼空间分辨率降低是否会影响五种不同蚂蚁的障碍物检测或避障能力。我们训练所有蚂蚁物种前往糖源喂食器。在它们返回的途中，我们在巢穴入口附近放置了一个障碍物。我们发现，空间分辨率较高的蚂蚁平均提前10厘米离开通道——障碍物两端之间的区域，这表明它们在路径中更早地检测到了障碍物。空间分辨率最低的蚂蚁只有在靠近障碍物时才会改变它们的观察方向。我们讨论了小型化对蚂蚁视觉导航能力的影响。
