Finally a paper about grooming patterns! On "early view" in American Journal of Primatology, is Rebecca J. Lewis's Grooming Patterns in Verreaux's Sifaka (free abstract). If you would like to read the article, let me know and I can send you the whole article in pdf.
I can definitely relate to the first sentence of this paper's abstract, "Lemur grooming has received very little attention in the literature". It has became apparent to me when I was visiting different graduate schools that professors would comment "Well, there aren't much grooming going on in the species that I study so you'll just be wasting time". While it is important to collect data on species that groom a lot, it is also important to document grooming patterns in species that don't groom a lot so that we can compare these data. Why don't these species groom as much? What alternative strategies are they using instead of grooming?
Well back to the article. As you might have guessed, it's about grooming patterns in Verreaux's Sifaka (Propithecus verreauxi). What's unique about prosimians grooming is that they don't groom with their fingers, instead they groom with their dental comb. In her paper, Lewis found is that these sifakas:
- Spend very little time allogrooming.
- Allogrooming happens on parts of the body that can be easily autogroomed (self groomed).
- While ectoparasite loads are greater in the rainy season, the rate of allogrooming did not increase.
- Allogrooming rates are influenced by sex and rank. Sifakas groom up the rank with females receiving more grooming than males. Males also tend to groom others more than females do.
- Allogrooming rates increased by 50-100% during mating season. Males tend to initiate grooming during mating season but generally are not reciprocated by females.
These results suggest that Verreaux's Sifaka used grooming as a social function, not as a health function. Lewis also posits that lemur grooming patterns do not differ from anthropoid grooming patterns as much as previously thought.