Bernáth Balázs, Anstett Victor, Guerin Patrick M
Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland.
Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000 Neuchâtel, Switzerland.
J Insect Physiol. 2016 Dec;95:8-16. doi: 10.1016/j.jinsphys.2016.08.011. Epub 2016 Sep 3.
The ability to learn plays a key role in tuning and adapting the behaviours of animals for their unpredictable biotopes. This also applies to insect vectors of disease. Anautogenous mosquitoes need to find both sugar and blood for survival and reproduction. Learning processes are expected to contribute to a mosquito's ability to undertake repeated feeding behaviours more efficiently with time, serving to decrease energy demands and avoid hazards. Here we report how visual learning by the Afrotropical malaria mosquito Anopheles gambiae allows it to readily associate visual cues with the quality of a sugar source. Circular black and white patterns were used as visual cues. An. gambiae females were conditioned in cages with a chequered pattern paired with sucrose and a concentric pattern paired with non-palatable sucrose-NaCl and with reverse combinations. Hours later, significantly higher numbers of feeding attempts were counted on sucrose paired with the chequered pattern following conditioning with the same combination. This was also the case on the concentric pattern paired with sucrose following conditioning with this combination. However, the effect was weaker than with sucrose paired with the chequered pattern. These findings indicate a differential capacity of visual stimuli to induce learning, explained in our experiments by a significantly higher mosquito appetence on sucrose paired with a chequered pattern that mimics floral shape. Training that induced a higher propensity for feeding attempts was found to allow the females to display a fast learning curve (<4min) on the less suitable concentric pattern paired with sucrose, several hours after conditioning on the chequered pattern paired with sucrose. This has important implications for mosquito behavioural ecology, suggesting that An. gambiae shows plasticity in its learning capacities that would allow it to readily turn to alternative sources for a sugar meal once initiated in the process by an appropriate stimulus combination.
学习能力在调整和适应动物行为以应对其不可预测的生物群落方面起着关键作用。这同样适用于疾病的昆虫传播媒介。非自育性蚊子需要获取糖分和血液才能生存和繁殖。学习过程有望帮助蚊子随着时间的推移更高效地进行重复取食行为，从而降低能量需求并避免危险。在此，我们报告了非洲疟疾蚊子冈比亚按蚊的视觉学习如何使其能够轻松地将视觉线索与糖源质量联系起来。圆形黑白图案被用作视觉线索。冈比亚按蚊雌蚊在笼子里接受训练，将棋盘格图案与蔗糖配对，同心圆图案与不可口的蔗糖 - 氯化钠配对，并进行反向组合。数小时后，在用相同组合进行训练后，与棋盘格图案配对的蔗糖上的取食尝试次数显著更多。在用该组合进行训练后，与蔗糖配对的同心圆图案上的情况也是如此。然而，这种效果比与棋盘格图案配对的蔗糖要弱。这些发现表明视觉刺激诱导学习的能力存在差异，在我们的实验中，这可以通过蚊子对与模仿花朵形状的棋盘格图案配对的蔗糖有显著更高的偏好来解释。发现在与蔗糖配对的棋盘格图案上进行训练后数小时，诱导更高取食尝试倾向的训练能使雌蚊在与蔗糖配对的不太合适的同心圆图案上呈现快速学习曲线（<4分钟）。这对蚊子行为生态学具有重要意义，表明冈比亚按蚊在学习能力上具有可塑性，一旦通过适当的刺激组合启动这一过程，它能够轻松转向替代糖源。
