Roups, particularly between semifossorial and the other groups (Table 3, Fig 3), suggesting that the use of different forest strata results in distinctions in isotopic niches. Although the average body mass varied largely among studied species (from 8.13 g for Juliomys pictipes to 1078.5 g for Didelphis aurita, Table 1), the correlation between body mass and isotopic niche differences was not significant in all statistical comparisons: for all species (Mantel; r = -0.15, p = 0.96), ii) for fpsyg.2017.00209 species within the same group and site (all p-values > 0.23) and iii) for species within the same group, site and locomotor habit (all p-PLOS ONE | DOI:10.1371/journal.pone.0152494 April 6,7 /Stable Isotopes and Diet of Small MammalsFig 2. Isotope plot depicting means isotope values (15N and 13C) of rodent (gray dots) and marsupial (blue dots) species from Atlantic rainforests, with respective standard isotope ellipses, for each studied site and all sites polled together. Isotope values were corrected downward 2.7 (for 15N) and 2.4 (for 13C) to account for trophic enrichment. Isotope values of the potential food resources are represented in boxplots. Species code: 1 = Didelphis aurita; 2 = Gracilinanus microtarsus; 3 = Juliomys pictipes; 4 = Marmosops incanus; 5 = Metachirus nudicaudatus; 6 = Monodelphis Americana; 7 = Monodelphis iheringi; 8 = Monodelphis scalops; 9 = Monodelphis sp.; 10 = Philander frenatus; 11 = Akodon cursor; 12 = Akodon montensis; 13 = Blarinomys breviceps; 14 = Brucepattersonius soricinus; 15 = Delomys dorsalis; 16 = Delomys sublineatus; 17 = Euryoryzomys russatus; 18 = Necromys lasiurus; 19 = Oligoryzomys nigripes; 20 = Sooretamys angouya; 21 = Thaptomys nigrita; 22 = Trinomys iheringi. doi:10.1371/journal.pone.0152494.gvalues > 0.36), indicating that isotopic niche partitioning is not mediated by body-size interspecific variations.DiscussionThe use of stable isotopes revealed distinct isotopic niche patterns among rodents and marsupials that VadadustatMedChemExpress PG-1016548 inhabit the largest continuous remnant in Atlantic rainforest in Brazil. Interestingly, we found that rodents and marsupials notably have distinct trophic niches, both in area and the degree of overlap. Marsupials’ isotopic niche space corresponds to only a small subset of the wide isotopic niche space occupied by rodent species, which have a large diversificationPLOS ONE | DOI:10.1371/journal.pone.0152494 April 6,8 /Stable Isotopes and Diet of Small MammalsTable 2. Richness, comparison between the areas of the isotopic niche space (SEAC) occupied by rodents vs. marsupials, and percentage of the niche ElbasvirMedChemExpress Elbasvir overlapped with the other group for marsupials and rodents in three sites of the Atlantic forest. Site Richness Rodents Botelho Itamambuca Vargem Grande All sites 18 10 9 22 17.28 20.11 28.3 18.86 SEAC (2) Marsupials 1.59 0.49 2.34 1.97 pvalue <0.001 <0.001 <0.001 <0.001 12.87 31.43 94.75 46.77 1.21 1.5 13.15 4.95 Marsupials' niche overlapped with rodents' niche scan/nst010 Rodents’ niche overlapped with marsupials’ nicheThe isotopic data were defined in delta notation () and reported in parts per mil () of international standards. doi:10.1371/journal.pone.0152494.tamong species in isotopic space. We also found that interspecific differences in locomotor habits, but not in body mass, are associated with divergences in the position of the isotopic niche space. This pattern indicates that use of distinct forest strata (e.g. ground, understory) may constitute a mechanism of isotopic niche partitioning i.Roups, particularly between semifossorial and the other groups (Table 3, Fig 3), suggesting that the use of different forest strata results in distinctions in isotopic niches. Although the average body mass varied largely among studied species (from 8.13 g for Juliomys pictipes to 1078.5 g for Didelphis aurita, Table 1), the correlation between body mass and isotopic niche differences was not significant in all statistical comparisons: for all species (Mantel; r = -0.15, p = 0.96), ii) for fpsyg.2017.00209 species within the same group and site (all p-values > 0.23) and iii) for species within the same group, site and locomotor habit (all p-PLOS ONE | DOI:10.1371/journal.pone.0152494 April 6,7 /Stable Isotopes and Diet of Small MammalsFig 2. Isotope plot depicting means isotope values (15N and 13C) of rodent (gray dots) and marsupial (blue dots) species from Atlantic rainforests, with respective standard isotope ellipses, for each studied site and all sites polled together. Isotope values were corrected downward 2.7 (for 15N) and 2.4 (for 13C) to account for trophic enrichment. Isotope values of the potential food resources are represented in boxplots. Species code: 1 = Didelphis aurita; 2 = Gracilinanus microtarsus; 3 = Juliomys pictipes; 4 = Marmosops incanus; 5 = Metachirus nudicaudatus; 6 = Monodelphis Americana; 7 = Monodelphis iheringi; 8 = Monodelphis scalops; 9 = Monodelphis sp.; 10 = Philander frenatus; 11 = Akodon cursor; 12 = Akodon montensis; 13 = Blarinomys breviceps; 14 = Brucepattersonius soricinus; 15 = Delomys dorsalis; 16 = Delomys sublineatus; 17 = Euryoryzomys russatus; 18 = Necromys lasiurus; 19 = Oligoryzomys nigripes; 20 = Sooretamys angouya; 21 = Thaptomys nigrita; 22 = Trinomys iheringi. doi:10.1371/journal.pone.0152494.gvalues > 0.36), indicating that isotopic niche partitioning is not mediated by body-size interspecific variations.DiscussionThe use of stable isotopes revealed distinct isotopic niche patterns among rodents and marsupials that inhabit the largest continuous remnant in Atlantic rainforest in Brazil. Interestingly, we found that rodents and marsupials notably have distinct trophic niches, both in area and the degree of overlap. Marsupials’ isotopic niche space corresponds to only a small subset of the wide isotopic niche space occupied by rodent species, which have a large diversificationPLOS ONE | DOI:10.1371/journal.pone.0152494 April 6,8 /Stable Isotopes and Diet of Small MammalsTable 2. Richness, comparison between the areas of the isotopic niche space (SEAC) occupied by rodents vs. marsupials, and percentage of the niche overlapped with the other group for marsupials and rodents in three sites of the Atlantic forest. Site Richness Rodents Botelho Itamambuca Vargem Grande All sites 18 10 9 22 17.28 20.11 28.3 18.86 SEAC (2) Marsupials 1.59 0.49 2.34 1.97 pvalue <0.001 <0.001 <0.001 <0.001 12.87 31.43 94.75 46.77 1.21 1.5 13.15 4.95 Marsupials' niche overlapped with rodents' niche scan/nst010 Rodents’ niche overlapped with marsupials’ nicheThe isotopic data were defined in delta notation () and reported in parts per mil () of international standards. doi:10.1371/journal.pone.0152494.tamong species in isotopic space. We also found that interspecific differences in locomotor habits, but not in body mass, are associated with divergences in the position of the isotopic niche space. This pattern indicates that use of distinct forest strata (e.g. ground, understory) may constitute a mechanism of isotopic niche partitioning i.
