We propose a mathematical model for a class of predator–prey systems more complex than the usual one, involving a commensalism effect consisting in an influence of the predator on the sustainability of the prey. This effect induces interesting new features, including bi-stability (two attractors with disjoint attraction basins). The question of the possibility of reaching a certain attractor starting from initial conditions with a small population of predators, which presents an interest from the vewpoint of the onset of the predator in evolution, is addressed. We propose two possibilities: the classical one involving adapted conditions in the far past and a new (up to our knowledge) one using biodiversity, specifically the presence of another predator which operates as a starter, being displaced in the sequel.

我们为一类比通常的捕食者-猎物系统更复杂的捕食者-猎物系统提出了一个数学模型，涉及一种共生效应，包括捕食者对猎物可持续性的影响。这种效应产生了有趣的新特征，包括双稳定性（两个具有不相交吸引盆的吸引子）。解决了从捕食者数量较少的初始条件开始达到某个吸引子的可能性的问题，这从捕食者在进化中开始的起点提出了兴趣。我们提出了两种可能性：经典的一种涉及过去适应的条件，一种新的（据我们所知）利用生物多样性，特别是另一种捕食者的存在，作为起始者，在续集中被取代。