Belisle C, Cresswell J
Departement de mathematiques et de statistique, Universite Laval, Sainte-Foy, Quebec, G1K 7P4, Canada
Theor Popul Biol. 1997 Aug;52(1):78-90. doi: 10.1006/tpbi.1997.1319.
We introduce a simple mathematical model to describe the behavior of a forager with a limited memory capacity in the presence of two prey types that differ in their energetic values. The model is used to analyze the effect of memory capacity on foraging behavior and on foraging energetics and it contrasts with classic optimal foraging theory, which implicitly assumes that the forager has an infinite memory capacity. Classic optimal foraging theory dictates that the low value prey type should be invariably excluded from the diet when the high value type exceeds some critical relative frequency and invariably consumed otherwise. Our model forager behaves similarly except that, as its memory capacity declines, it is increasingly predisposed to consume the low value prey when it is suboptimal to do so. Nevertheless, our analysis indicates that the energetic efficiency of a forager with an infinite memory capacity can be approximated by a forager with a memory of modest capacity, perhaps one that contains information about 5-20 previously consumed prey items. In our model, memory constraints necessarily result in so-called "partial preferences" being exercised towards the low value prey type. Thus, limited memory capacity offers a possible explanation for observed violations of the "zero-one" rule of optimal diet composition. We also find a resemblance to a sigmoidal shape in the relationship between the representation of each prey type in the diet and its relative frequency. Thus, the memory-constrained forager exhibits behavior that resembles the type III functional response. Therefore, it is possible that memory constraints such as we envisage can contribute to the explanation of both partial preferences and functional responses. Copyright 1997 Academic Press
我们引入了一个简单的数学模型，以描述在存在两种能量值不同的猎物类型时，具有有限记忆容量的觅食者的行为。该模型用于分析记忆容量对觅食行为和觅食能量学的影响，并且它与经典的最优觅食理论形成对比，经典最优觅食理论隐含地假设觅食者具有无限的记忆容量。经典最优觅食理论规定，当高价值猎物类型超过某个临界相对频率时，低价值猎物类型应始终从食谱中排除，否则应始终被食用。我们模型中的觅食者行为类似，只是随着其记忆容量下降，在次优情况下它越来越倾向于食用低价值猎物。然而，我们的分析表明，具有无限记忆容量的觅食者的能量效率可以由具有适度容量记忆的觅食者近似，也许是一个包含大约5 - 20个先前食用过的猎物项目信息的记忆。在我们的模型中，记忆限制必然导致对低价值猎物类型表现出所谓的“部分偏好”。因此，有限的记忆容量为观察到的违反最优饮食组成的“零一”规则提供了一种可能的解释。我们还发现，每种猎物类型在食谱中的占比与其相对频率之间的关系类似于S形。因此，受记忆限制的觅食者表现出类似于III型功能反应的行为。所以，像我们所设想的这种记忆限制有可能有助于解释部分偏好和功能反应。版权所有1997学术出版社
