The geographic distribution of rodent granivory and cheek pouches across North America

Seeds are an important food resource for many rodents. One of the specializations that many granivorous rodents exhibit to increase their efficiency in harvesting seeds is cheek pouches. However, many rodent species lack cheek pouches. We propose that the presence or absence of cheek pouches is related to seed size and the productivity of the habitat where those rodents reside. Location North America – United States and Canada. Taxon Granivorous rodents. We divided granivorous rodents into those species with and without cheek pouches. We then compiled a list of plant species (n = 389) that are known or suspected to be dispersed by these rodents via scatter hoarding the seeds in soil and compared the richness distributions of small (≤10 mm) and large seeds (>10 mm) to the distributions of rodents with and without cheek pouches. Large seeds are generally too large to fit into cheek pouches so they are usually carried one at a time with the incisors. Most rodents with ch...种子是多数啮齿类的重要食物资源。许多食籽啮齿类（granivorous rodents）为提升种子采食效率演化出的特化结构之一便是颊囊（cheek pouches）。然而，诸多啮齿类物种并不具备颊囊。本研究提出，颊囊的有无与种子大小以及啮齿类栖息生境的生产力存在关联。 研究区域：北美洲——美国与加拿大。 研究类群：食籽啮齿类。 我们将食籽啮齿类划分为具颊囊与无颊囊两类。随后整理了389种已知或疑似可通过啮齿类将种子分散贮藏于土壤中完成传播的植物物种（n = 389），并对比了小种子（≤10 mm）与大种子（>10 mm）的物种丰富度分布，以及具颊囊与无颊囊啮齿类的分布格局。大种子通常因体积过大无法装入颊囊，因此多通过门齿单次携带一枚。多数具颊囊的啮齿类……