The diademed sifaka (Propithecus diadema) is potentially the world’s most colorful lemur species. You’d think that would make them easy to find in the green rainforests of eastern Madagascar, especially since they are the second largest living lemur, but they can camouflage surprisingly well in the shadows.
You may wonder why sifaka (pronounced she-FAK) are called sifaka. The term is actually onomatopoetic, meaning that sifaka have a vocalization that sort of sounds like she-FAK. The eastern sifaka—which includes 4 species—has a call that I think sounds more like a sneeze and then a lip smack. Most Malagasy people call the sifaka simpona although in the western parts of Madagascar, the local people actually refer to them as sifaka.
The sifaka’s diet changes seasonally and can include young leaves, fruit, seeds, flowers, and soil2. It is thought that sifaka eat soil because it neutralizes some of the toxins found in their other food items. Having such a flexible diet allows sifaka to persist in fragmented forests3, albeit with decreased physical health4. Since it takes a while to digest leaves, sifaka typically have one or more “siesta” times during the day where they all take a nap in one or several trees. After their midday siesta they continue to feed on leaves and other things until they eventually find the tree that they will sleep in. Sifaka sleep high in trees in little balls snuggled up against one another, potentially to avoid predation by fossa—a Malagasy-endemic carnivoran species—which are active during the night.
Although there have been various studies about the diet and ability of diademed sifaka to persist in fragmented habitats, not much is known about their social behavior. Like other sifaka species, they live in small to medium groups that can include one or more females and one or more males along with their offspring. Somewhat unique to lemurs, most species are female-dominant. In most primates, the males are dominant over the females, which means that they have more control over food, space, and other resources. In lemurs though, it is the females that are dominant over the males5, which makes them an ideal study species to elucidate dominance interactions and social structure dynamics6. Sifaka dominance relationships are maintained through a variety of aggressive (such as hitting or biting) and submissive (such as chattering or avoiding) behaviors. Other sifaka social behaviors include grooming and playing (look for an upcoming “Field Notes” article on sifaka play!).
This elusive lemur is critically endangered, with potentially 1,000-10,000 animals left in the wild1 due to extensive habitat loss and fragmentation. Like most fauna endemic to Madagascar, sifaka now live in isolated habitat patches that are surrounded by an ever-expanding human population.
[By: Meredith Lutz]
1Gould, L., & Sauther, M. L. (Eds.). (2006). Lemurs: Ecology and adaptation: Springer.
2Powzyk, J. A., & Mowry, C. B. (2003). Dietary and feeding differences between sympatric Propithecus diadema diadema and Indri indri. International Journal of Primatology, 24, 1143-1162.
3Irwin, M. T. (2008). Feeding ecology of Propithecus diadema in forest fragments and continuous forest. International Journal of Primatology, 29, 95-115.
4Irwin, M. T., Junge, R. E., Raharison, J.-L., & Samonds, K. E. (2010). Variation in physiological health of diademed sifakas across intact and fragmented forest at Tsinjoarivo, eastern Madagascar. American Journal of Primatology, 72, 1013-1025.
5Petty, J. M. A., & Drea, C. M. (2015). Female rule in lemurs is ancestral and hormonally mediated. Scientific Reports, 5.
6Lewis, R. J. (2002). Beyond dominance: The importance of leverage. Quarterly Review of Biology, 77, 149-164.