Table S1. Study site characteristics. Species Coordinates Study site Forest size (ha) Forest type Forest Seasonal disturbance rainfall (mm) category Primary Rainy: 396.7 Dry: 83.7 Seasonal temperature (°C) Rainy: 27.5 Dry: 26.1 Alouatta pigra 17°29’N, 92°03’W Palenque National Park, Mexico CK 900 Evergreen tropical forest 60 Evergreen tropical forest Evergreen tropical forest Evergreen tropical forest Semi-deciduous tropical forest Secondary Rainy: 27.5 Dry: 26.1 Rainy: 27.5 Dry: 26.1 Rainy: 27.5 Dry: 26.1 Rainy: 27.5 Dry: 28.0 PC 120 CBTA 26 El Tormento, Mexico 2,100 18°30’N, 90°50’W PE 2.61 Semi-deciduous tropical forest Secondary 18°29’N, 90°48’W FE 2.36 Semi-deciduous tropical forest Secondary 18°30’N, 90°48’W CH 9.0 Semi-deciduous tropical forest Secondary 10º26’N, 83º47’W La Suerte Biological Field Station 20 Evergreen tropical forest Primary 10º26’N, 83º47’W La Suerte 250 Biological Field Station II Evergreen tropical forest Secondary 11°26' N, 85°31' W Maderas Volcano National Park, Nicaragua COF 3,500 Semi-deciduous tropical forest Primary 3,500 Semi-deciduous tropical forest Secondary 11°24' N, 85°31' W WTF 3,500 Semi-deciduous tropical forest Secondary 11°26' N, 85°32' W MYS 3,500 Semi-deciduous tropical forest Secondary 17°29’N, 92°01’W 17°29’N, 92°01’W 17°31’N, 91°59’W 18°16’N, 90°43’W Alouatta palliata 11°26' N, 85°32' W Secondary Secondary Primary Rainy: 396.7 Dry: 83.7 Rainy: 396.7 Dry: 83.7 Rainy: 396.7 Dry: 83.7 Rainy: 212.6 ± 49 Dry: 30.6 ± 29 Rainy: 212.6 ± 49 Dry: 30.6 ± 29 Rainy: 212.6 ± 49 Dry: 30.6 ± 29 Rainy: 212.6 ± 49 Dry: 30.6 ± 29 Rainy: 263.3 ± 113.7 Dry: 215.8 ± 219.8 Rainy: 263.3 ± 113.7 Dry: 215.8 ± 219.8 Rainy: 198.5 ± 145.5 Dry: 24.7 ± 17.5 Rainy: 198.5 ± 145.5 Dry: 24.7 ± 17.5 Rainy: 198.5 ± 145.5 Dry: 24.7 ± 17.5 Rainy: 198.5 ± 145.5 Dry: 24.7 ± 17.5 Rainy: 27.5 Dry: 28.0 Rainy: 27.5 Dry: 28.0 Rainy: 27.5 Dry: 28.0 Rainy: 30.6 ± 1.0 Dry: 28.5 ± 1.7 Rainy: 30.6 ± 1.0 Dry: 28.5 ± 1.7 Rainy: 26.6 ± 0.5 Dry: 26.1 ± 0.6 Rainy: 26.6 ± 0.5 Dry: 26.1 ± 0.6 Rainy: 26.6 ± 0.5 Dry: 26.1 ± 0.6 Rainy: 26.6 ± 0.5 Dry: 26.1 ± 0.6 Table S2. Average relative abundances (± standard deviation) of microbial taxa that differed significantly (corrected p < 0.05) between A. pigra and A. palliata. Alouatta pigra Microbial Taxon AVG STDEV Alouatta palliata AVG STDEV Euryarchaeota 0.12% 0.16% 0.37% 0.16% Actinobacteria 0.32% 0.18% 0.11% 0.05% Bacteroidetes 18.76% 4.63% 22.97% 4.76% Elusimicrobia 0.00% 0.01% 0.02% 0.02% 51.41% 7.86% 38.19% 5.47% Synergistetes 0.02% 0.03% 0.00% 0.00% Actinobacteria 0.00% 0.01% 0.03% 0.02% Firmicutes Clostridia 47.80% 7.84% 35.36% 5.69% Coriobacteriia 0.29% 0.17% 0.09% 0.03% Deltaproteobacteria 0.18% 0.22% 0.08% 0.11% Elusimicrobia 0.00% 0.01% 0.02% 0.02% Epsilonproteobacteria 0.14% 0.16% 0.61% 0.38% Erysipelotrichi 2.40% 1.13% 0.76% 0.40% Synergistia 0.02% 0.03% 0.00% 0.00% Thermoplasmata 0.08% 0.12% 0.36% 0.16% Verrucomicrobiae 0.11% 0.19% 0.00% 0.00% Bifidobacteriales 0.00% 0.00% 0.02% 0.01% Campylobacterales 0.14% 0.16% 0.61% 0.38% 47.61% 7.85% 35.28% 5.67% Coriobacteriales 0.29% 0.17% 0.09% 0.03% Desulfovibrionales 0.18% 0.22% 0.08% 0.11% E2 0.08% 0.12% 0.36% 0.16% Elusimicrobiales 0.00% 0.01% 0.02% 0.02% Erysipelotrichales 2.40% 1.13% 0.76% 0.40% Synergistales 0.02% 0.03% 0.00% 0.00% Verrucomicrobiales 0.11% 0.19% 0.00% 0.00% Bifidobacteriaceae 0.00% 0.00% 0.02% 0.01% Campylobacteraceae 0.00% 0.01% 0.46% 0.34% Coriobacteriaceae 0.29% 0.17% 0.09% 0.03% Elusimicrobiaceae 0.00% 0.01% 0.02% 0.02% Erysipelotrichaceae 2.40% 1.13% 0.76% 0.40% Lactobacillaceae 0.00% 0.00% 0.01% 0.02% Micrococcaceae 0.00% 0.00% 0.01% 0.01% 21.68% 5.06% 11.08% 3.05% S24-7 1.20% 1.51% 1.96% 0.49% Staphylococcaceae 0.00% 0.00% 0.01% 0.01% Verrucomicrobiaceae 0.11% 0.19% 0.00% 0.00% Victivallaceae 0.00% 0.00% 0.19% 0.11% YRC22 0.00% 0.00% 1.35% 1.45% Clostridiales Ruminococcaceae Tannerella 0.04% 0.06% 0.11% 0.10% Staphylococcus 0.00% 0.00% 0.01% 0.01% Roseburia 0.56% 0.56% 3.17% 1.69% p-75-a5 0.00% 0.01% 0.03% 0.03% Oscillospira 3.06% 1.11% 1.45% 0.79% Lactobacillus 0.00% 0.00% 0.01% 0.02% Gardnerella 0.00% 0.00% 0.01% 0.01% Faecalibacterium 4.56% 1.52% 1.00% 0.92% Dialister 0.57% 0.42% 0.06% 0.05% Coprococcus 2.66% 1.57% 1.07% 0.36% Clostridium 0.89% 0.73% 0.12% 0.07% Campylobacter 0.00% 0.01% 0.46% 0.34% Bifidobacterium 0.00% 0.00% 0.01% 0.01% Anaerostipes 0.00% 0.00% 0.09% 0.12% Akkermansia 0.10% 0.19% 0.00% 0.00% Table S3. Average relative abundances (± standard deviation) of microbial taxa that differed significantly (corrected p < 0.05) between the rainforest and the semideciduous forest for both A. pigra and A. palliata. ns indicates no significant difference detected. Alouatta pigra Rainforest Alouatta palliata Dry Forest Rainforest Dry Forest AVG STDEV AVG STDEV AVG STDEV AVG STDEV Cyanobacteria 3.63% 3.11% 9.51% 5.60% ns ns ns ns Firmicutes 51.41% 7.86% 45.78% 6.82% ns ns ns ns Tenericutes 4.80% 2.90% 1.79% 1.66% 4.87% 1.46% 9.61% 2.40% Verrucomicrobia 0.87% 1.84% 0.37% 0.85% 1.18% 1.79% 5.50% 1.49% Euryarchaeota ns ns ns ns 0.37% 0.16% 0.04% 0.03% Bacteroidetes ns ns ns ns 22.97% 4.76% 12.09% 5.00% Lentisphaerae ns ns ns ns 0.19% 0.11% 0.04% 0.07% Actinobacteria 0.00% 0.01% 0.05% 0.03% 0.03% 0.02% 0.08% 0.04% 4C0d-2 3.53% 3.06% 9.15% 5.63% ns ns ns ns Chloroplast 0.09% 0.10% 0.35% 0.27% ns ns ns ns Clostridia 47.80% 7.84% 41.93% 6.99% ns ns ns ns Alphaproteobacteria 1.54% 0.89% 0.13% 0.17% ns ns ns ns Deltaproteobacteria 0.18% 0.22% 0.44% 0.32% ns ns ns ns Epsilonproteobacteria 0.14% 0.16% 0.34% 0.23% ns ns ns ns Mollicutes 4.80% 2.90% 1.79% 1.66% 4.87% 1.46% 9.61% 2.40% Opitutae 0.76% 1.85% 0.00% 0.01% 1.18% 1.79% 5.49% 1.49% Thermoplasmata ns ns ns ns 0.36% 0.16% 0.02% 0.02% Bacteroidia ns ns ns ns 18.99% 3.41% 11.59% 5.24% Betaproteobacteria ns ns ns ns 0.17% 0.15% 0.49% 0.26% Bifidobacteriales 0.00% 0.00% 0.03% 0.02% 0.02% 0.01% 0.05% 0.03% YS2 3.53% 3.06% 9.15% 5.63% ns ns ns ns Streptophyta 0.09% 0.10% 0.35% 0.27% ns ns ns ns RF32 1.50% 0.89% 0.06% 0.17% ns ns ns ns Rickettsiales 0.01% 0.02% 0.06% 0.05% ns ns ns ns Neisseriales 0.01% 0.02% 0.00% 0.00% ns ns ns ns Desulfovibrionales 0.18% 0.22% 0.44% 0.32% ns ns ns ns Campylobacterales 0.14% 0.16% 0.34% 0.23% ns ns ns ns Enterobacteriales 0.02% 0.04% 0.10% 0.09% 1.88% 4.99% 0.07% 0.03% RF39 4.79% 2.90% 1.79% 1.65% 4.87% 1.46% 9.61% 2.40% E2 ns ns ns ns 0.36% 0.16% 0.02% 0.02% Bacteroidales ns ns ns ns 18.99% 3.41% 11.59% 5.24% Bacillales ns ns ns ns 0.01% 0.01% 0.00% 0.00% Victivallales ns ns ns ns 0.19% 0.11% 0.04% 0.07% Pseudomonadales ns ns ns ns 0.21% 0.48% 0.00% 0.00% Rikenellaceae 0.00% 0.00% 0.03% 0.02% 0.02% 0.01% 0.05% 0.03% Bacteroidaceae 0.00% 0.01% 0.06% 0.05% 0.00% 0.01% 0.24% 0.11% Prevotellaceae 4.29% 1.79% 9.90% 5.49% ns ns ns ns S24-7 1.20% 1.51% 0.52% 0.83% ns ns ns ns Lactobacillaceae 0.00% 0.00% 0.01% 0.01% ns ns ns ns Rikenellaceae ns ns ns ns 0.00% 0.00% 0.05% 0.03% Staphylococcaceae ns ns ns ns 0.01% 0.01% 0.00% 0.00% Clostridiaceae ns ns ns ns 0.20% 0.43% 1.00% 1.17% Lachnospiraceae ns ns ns ns 15.13% 5.40% 8.98% 2.82% Peptococcaceae ns ns ns ns 0.00% 0.00% 0.02% 0.02% Ruminococcaceae ns ns ns ns 11.08% 3.05% 8.01% 2.43% Veillonellaceae ns ns ns ns 0.71% 0.42% 1.43% 0.55% Victivallaceae ns ns ns ns 0.19% 0.11% 0.04% 0.07% Alcaligenaceae ns ns ns ns 0.00% 0.00% 0.01% 0.02% Pseudomonadaceae ns ns ns ns 0.03% 0.04% 0.00% 0.00% mitochondria 0.01% 0.02% 0.05% 0.06% ns ns ns ns Neisseriaceae 0.01% 0.02% 0.00% 0.00% ns ns ns ns Helicobacteraceae 0.14% 0.16% 0.34% 0.24% ns ns ns ns Enterobacteriaceae 0.02% 0.04% 0.10% 0.09% 1.88% 4.99% 0.07% 0.03% Bifidobacterium 0.00% 0.00% 0.03% 0.02% 0.01% 0.01% 0.05% 0.03% Bacteroides 0.00% 0.01% 0.06% 0.05% 0.00% 0.01% 0.24% 0.11% Clostridium 0.89% 0.73% 0.20% 0.20% ns ns ns ns Coprococcus 2.66% 1.57% 0.70% 0.73% ns ns ns ns Lachnospira 0.86% 0.70% 0.00% 0.01% 0.83% 0.75% 0.00% 0.01% Megasphaera 0.00% 0.00% 0.02% 0.02% ns ns ns ns Bulleidia 0.20% 0.18% 0.07% 0.09% 0.12% 0.08% 0.01% 0.02% RFN20 0.54% 0.49% 0.00% 0.00% ns ns ns ns Staphylococcus ns ns ns ns 0.01% 0.01% 0.00% 0.00% Lactobacillus ns ns ns ns 0.01% 0.02% 0.00% 0.00% Blautia ns ns ns ns 0.01% 0.01% 0.04% 0.04% Roseburia ns ns ns ns 3.17% 1.69% 0.62% 0.27% rc4-4 ns ns ns ns 0.00% 0.00% 0.02% 0.02% Dialister ns ns ns ns 0.06% 0.05% 0.84% 0.68% Veillonella ns ns ns ns 0.00% 0.00% 0.01% 0.01% p-75-a5 ns ns ns ns 0.03% 0.03% 0.00% 0.00% Sutterella ns ns ns ns 0.00% 0.00% 0.01% 0.02% Escherichia ns ns ns ns 0.00% 0.00% 0.05% 0.03% Pseudomonas ns ns ns ns 0.03% 0.04% 0.00% 0.00% Table S4: Average relative abundances (± standard deviation) of microbial taxa that differed significantly (corrected p < 0.05) across seasons and habitats for A. pigra in the rainforest (Palenque National Park). (1) = differs by season in primary forest; (2) = differs by habitat disturbance in high fruit season; (3) = differs by habitat disturbance in low fruit season. Primary High Fruit Secondary Low Fruit High Fruit Low Fruit Microbial Taxon AVG STDEV AVG STDEV AVG STDEV AVG STDEV Euryarchaeota (2) 0.12% 0.16% 0.92% 1.84% 3.37% 4.49% 2.64% 4.03% Verrucomicrobia (2) 0.87% 1.84% 2.24% 4.14% 4.64% 3.98% 6.77% 9.26% Firmicutes (2) 51.41% 7.86% 44.29% 7.55% 40.66% 13.27% 45.65% 13.17% Cyanobacteria (3) 3.63% 3.11% 5.36% 3.00% 4.71% 2.84% 2.88% 1.71% Erysipelotrichaceae (1) 2.40% 1.13% 1.15% 0.96% 1.52% 1.32% 1.42% 0.75% Ruminococcaceae (1, 2) 21.68% 5.06% 15.41% 4.03% 14.07% 6.75% 18.91% 9.35% Helicobacteraceae (3) 0.14% 0.16% 0.14% 0.08% 0.28% 0.15% 0.40% 0.40% Faecalibacterium (2) 4.56% 1.52% 4.17% 1.84% 2.21% 1.07% 2.61% 2.23% Table S5. Average relative abundances (± standard deviation) of microbial taxa that differed significantly (corrected p < 0.05) across seasons and habitats for A. pigra in the semi-deciduous forest (El Tormento). (1) = differs by season in primary forest; (3) = differs by habitat disturbance in low fruit season. Primary High Fruit Secondary Low Fruit High Fruit Low Fruit Microbial Taxon AVG STDEV AVG STDEV AVG STDEV AVG STDEV Actinobacteria (1) 0.37% 0.27% 0.63% 0.23% 0.34% 0.19% 0.58% 0.28% Cyanobacteria (1, 3) 9.51% 5.60% 3.02% 2.54% 7.96% 3.84% 11.02% 5.06% Porphyromonadaceae (3) 0.07% 0.06% 0.12% 0.10% 0.07% 0.09% 0.03% 0.02% Tannerella (3) 0.07% 0.06% 0.12% 0.10% 0.07% 0.09% 0.02% 0.01% Table S6: Average relative abundances (± standard deviation) of microbial taxa that differed significantly (corrected p < 0.05) across seasons and habitats for A. palliata in the semi-deciduous forest (Ometepe Island). (4) = differs by season in secondary forest. Primary High Fruit Microbial Taxon Secondary Low Fruit High Fruit Low Fruit AVG STDEV AVG STDEV AVG STDEV AVG STDEV Firmicutes (4) 31.72% 5.32% 43.46% 8.02% 38.81% 7.95% 49.45% 7.11% Verrucomicrobia (4) 5.50% 1.49% 7.34% 6.04% 5.77% 2.59% 3.10% 2.27% Bifidobacteriaceae (4) 0.05% 0.03% 0.00% 0.00% 0.03% 0.03% 0.00% 0.00% Lachnospiraceae (4) 8.98% 2.82% 14.49% 4.89% 10.30% 2.51% 15.32% 4.54% Enterobacteriaceae (4) 0.07% 0.03% 0.02% 0.02% 0.06% 0.03% 0.03% 0.05% Bifidobacterium (4) 0.05% 0.03% 0.00% 0.00% 0.03% 0.03% 0.00% 0.00% Table S7. Different physiological and anatomical traits of Alouatta palliata and A. pigra Trait Anatomical Physiological Socioecological and reproductive Alouatta pigra Male body mass (kg) Alouatta palliata 5.80 ± 0.7 7.6 ± 1.1 Kelaita et al. 2011 Female body mass (kg) 4.39 ± 0.5 5.68 ± 0.6 Kelaita et al. 2011 Body mass dimorphism Canine height dimorphism‡ Neonatal weight (g) 1.17 – 1.32* 1.33 Garber et al. 2015 1.72 1.60 Kelaita et al. 2011 320 480 Kappeler & Pereira 2003 Testicular volume (cm3) Endocranial volume (cc) PGLS res ECV† 22.66 ± 10.9 11.33 ± 3.8 49.88 51.13 Isler et al. 2008 -0.156 -0.276 Allen & Kay 2011 White blood cell count (×103/μL) Red blood cell count (×106/μL) Mean gut transit time (h) Mean retention time (h) 12.49 ± 4.08 7.95 ± 2.45 3.73 ± 0.31 3.49 ± 0.64 20.4 22.7 ± 0.8 30.6 ± 3.8 36.9 ± 7.4 Group size 15.2 (4 - 59) 6.2 (2 - 10.7) 1.1 ± 0.2 2.5 ± 0.8 19.9 – 22.5 15.5 16 18.3 Adult sex ratio (F/M) Interbirth interval (mo) Ovarian cycle length (d) *Range across different subspecies ‡Mean male/mean female †Phylogenetically corrected residuals of endocranial volume (ECV) on body mass References Kelaita et al. 2011 Canales-Espinosa et al. 2015 Canales-Espinosa et al. 2015 Milton 1984; EspinosaGomez et al. 2009 Edwards & Ullrey 1999; Espinosa-Gomez et al. 2009 Dias & Rangel-Negrín 2015 Di Fiore et al. 2011 Fedigan & Rose 1995; Di Fiore et al. 2011; Dias et al. 2011 Fedigan & Rose 1995; Van Belle et al. 2009 References Allen KL, RF Kay. 2011. 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