Programa de Pós-Graduação em Ecologia, Instituto de Biologia, Universidade Estadual de Campinas, Campinas SP, Brazil.
Laboratório de Biossistemática Animal, Universidade Estadual do Sudoeste da Bahia, Itapetinga BA, Brazil.
PLoS One. 2014 Feb 26;9(2):e90369. doi: 10.1371/journal.pone.0090369. eCollection 2014.
Ants frequently interact with fleshy fruits on the ground of tropical forests. This interaction is regarded as mutualistic because seeds benefit from enhanced germination and dispersal to nutrient-rich microsites, whereas ants benefit from consuming the nutritious pulp/aril. Considering that the process of deforestation affects many attributes of the ecosystem such as species abundance and composition, and interspecific interactions, we asked whether the interaction between ants and fallen fleshy fruits in the Brazilian Atlantic forest differs between human-created fragments and undisturbed forests. We controlled diaspore type and quantity by using synthetic fruits (a plastic 'seed' covered by a lipid-rich 'pulp'), which were comparable to lipid-rich fruits. Eight independent areas (four undisturbed forests, and four disturbed forest fragments) were used in the field experiment, in which we recorded the attracted ant species, ant behaviour, and fruit removal distance. Fruits in undisturbed forest sites attracted a higher number of species than those in disturbed forests. Moreover, the occurrence of large, fruit-carrying ponerine ants (Pachycondyla, Odontomachus; 1.1 to 1.4 cm) was higher in undisturbed forests. Large species (≥3 mm) of Pheidole (Myrmicinae), also able to remove fruits, did not differ between forest types. Following these changes in species occurrence, fruit displacement was more frequent in undisturbed than in disturbed forests. Moreover, displacement distances were also greater in the undisturbed forests. Our data suggest that fallen fleshy fruits interacting with ants face different fates depending on the conservation status of the forest. Together with the severe loss of their primary dispersers in human-disturbed tropical forest sites, vertebrate-dispersed fruits may also be deprived of potential ant-derived benefits in these habitats due to shifts in the composition of interacting ant species. Our data illustrate the use of synthetic fruits to better understand the ecology of ant-fruit interactions in variable ecological settings, including human-disturbed landscapes.
蚂蚁经常在热带森林的地面上与肉质果实互动。这种互动被认为是互利的，因为种子受益于增强的萌发和传播到营养丰富的小生境，而蚂蚁则受益于消耗营养丰富的果肉/假种皮。考虑到森林砍伐过程会影响生态系统的许多属性，如物种丰富度和组成以及种间相互作用，我们想知道在巴西大西洋森林中，蚂蚁与掉落的肉质果实之间的相互作用是否在人为创造的碎片和未受干扰的森林之间有所不同。我们通过使用合成果实（一种覆盖有富含脂质的“果肉”的塑料“种子”）来控制 Diaspore 类型和数量，这些果实与富含脂质的果实相当。在野外实验中，我们使用了八个独立的区域（四个未受干扰的森林和四个受干扰的森林碎片），记录了吸引的蚂蚁种类、蚂蚁行为和果实移除距离。未受干扰森林地区的果实吸引了更多的物种，而受干扰森林地区的果实则较少。此外，在未受干扰的森林中，体型较大、携带果实的兵蚁（Pachycondyla、Odontomachus；1.1 到 1.4 厘米）的出现频率更高。体型较大（≥3 毫米）的能够移除果实的 Pheidole（Myrmicinae）在森林类型之间没有差异。随着物种出现的这些变化，果实在未受干扰的森林中比在受干扰的森林中更容易发生位移。此外，在未受干扰的森林中，位移距离也更大。我们的数据表明，与蚂蚁相互作用的肉质果实会根据森林的保护状况而面临不同的命运。与在人为干扰的热带森林地区主要传播者严重丧失的情况一起，脊椎动物传播的果实也可能由于相互作用的蚂蚁物种组成的变化而失去潜在的蚂蚁衍生的益处。我们的数据说明了使用合成果实来更好地理解在不同生态环境中蚂蚁与果实相互作用的生态学，包括人为干扰的景观。
