Koppik Mareike, Hoffmeister Thomas S, Brunkhorst Sven, Kieß Melanie, Thiel Andra
Faculty 02 Biology/Chemistry, Institute of Ecology, University of Bremen, Leobener Straße NW2, 28359, Bremen, Germany.
Anim Cogn. 2015 May;18(3):593-604. doi: 10.1007/s10071-014-0828-y. Epub 2014 Dec 19.
The ability to learn is key to behavioral adaptation to changing environments. Yet, learning rate and memory retention can vary greatly across or even within species. While interspecific differences have been attributed to ecological context or life history constraints, intraspecific variability in learning behavior is rarely studied and more often, ignored: inferences of the cognitive abilities of a species are most of the time made from experiments using individuals of a single population. Here, we show that learning of host-associated cues in the parasitic wasp Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae) shows considerable interpopulation variability, which is at least partly, genetically determined. The strengths of the learning response differed predictably between populations and also varied with the rewarding stimulus. We tested memory retention in a genetically diverse strain and in an iso-female line, bearing a low genetic variability. In addition, we compared our findings with published studies on a third strain using a meta-analytical approach. Our findings suggest that all three strains differ in memory formation from each other. We conclude that, even though the associative learning of host cues is most likely under strong natural selection in parasitoid wasps, considerable genetic variability is maintained at the population as well as at the species level in N. vitripennis.
学习能力是行为适应不断变化环境的关键。然而，学习速度和记忆保持能力在不同物种之间甚至在同一物种内部都可能有很大差异。虽然种间差异被归因于生态环境或生活史限制，但学习行为的种内变异性很少被研究，而且更常被忽视：一个物种认知能力的推断大多时候是基于使用单一群体个体的实验得出的。在这里，我们表明寄生蜂丽蝇蛹集金小蜂（Walker）（膜翅目：金小蜂科）对宿主相关线索的学习表现出相当大的种群间变异性，这至少部分是由基因决定的。学习反应的强度在不同种群之间可预测地不同，并且也随奖励刺激而变化。我们在一个基因多样的品系和一个遗传变异性低的同雌系中测试了记忆保持能力。此外，我们使用元分析方法将我们的发现与关于第三个品系的已发表研究进行了比较。我们的发现表明，这三个品系在记忆形成方面彼此不同。我们得出结论，尽管宿主线索的联想学习在寄生蜂中很可能受到强烈的自然选择，但丽蝇蛹集金小蜂在种群以及物种水平上都保持着相当大的遗传变异性。
