The gut microbiota appears to compensate for seasonal diet variation in the wild black howler monkey (Alouatta pigra).
Amato KR, Leigh SR, Kent A, Mackie RI, Yeoman CJ, Stumpf RM, Wilson BA, Nelson KE, White BA, Garber PA. The gut microbiota appears to compensate for seasonal diet variation in the wild black howler monkey (Alouatta pigra). Microb Ecol. 2015 Feb; 69(2):434-43.