The relationship between rodents and oak species has been interpreted, based on their results, as a range of relationships varying from the extreme in which rodents behave as predators to the extreme in which the rodent collaborates by participating in the dissemination of their acorns. Here we have studied the relationships between three rodent species and six oak species. We obtained results corresponding to the two extremes.
The most abundant oak species in the study area have high concentrations of nutrients, low concentrations of tannins and thin shells. The higher concentration of nutrients favors the ability of acorns to settle. This may be one of the multiple causes of their abundance in the area. This high availability of nutrients attracts the attention of the three rodent species to incorporate them into their diet. Two of these rodent species are also hoarders so they transport acorns to protected places where they can germinate and emerge. This transporting activity would be sufficient to call this relationship with the oaks as collaborative, but they also show a behavior that partially consumes the acorns, initiating them at the basal end and preserving the embryo, which brings this relationship even closer to the mutualistic end of collaboration. With this behavior, the two rodent species participate in the dissemination of acorns improving their efficiency, which could be another of the multiple causes of the abundance of these oak species in the area. The predator rodent species in this study, recently arrived in the study area, may decrease the dispersal efficiency of the oaks because it interferes with the relationship of the dispersers by destroying the acorns.
The two oak species that exhibit predation avoidance characteristics are not consumed, but neither are they transported or disseminated.
