The two species of ruffed lemur---the red, and the black-and-white---are the largest of all lemurs. Along with their size, these primates draw attention with their handsome pelage and renowned bellows. Red ruffed lemurs are, as their name suggests, a rich, burnt crimson on their dorsal sides; their faces, undersides, and tail are black. Black-and-white ruffed lemurs come in a few color patterns depending on the subspecies, but all are some combination of their namesake hues. Despite the distinctiveness of the two species as a whole, differentiating male ruffed lemurs from females is rather difficult.
Instructions
1. Look for the reproductive organs if the animal is captive, sedated or dead. This is the surest way---as with most creatures---to determine the lemur's gender. Females have six mammary glands.
2. Considering an animal's size is a useful measure in any study, but it won't help determining the sex of a ruffed lemur. The National Primate Research Center reports the following average dimensions for wild individuals: Female ruffed lemurs average about 7.3 pounds (with a range between 5.7 and 8.8 pounds) while males average 7.9 pounds (with a range of 6.2 to 9). Both sexes are typically between about 17 and 23 inches in length, not counting the 24-inch tail. The center reports that "no sexual dimorphism is seen between males and females nor are differences in coloration evident between the sexes." Lemurs in general do not exhibit sexual dimorphism---which refers to physical differences between the sexes---and females are typically the dominant gender. These traits are a rarity among most primates.
3. Observe the lemur's behavior, if possible. Ruffed lemurs typically live and travel in small groups that splinter into male/female pairs. An observation of mating will tend to point you in the right direction. The reproductive organs of both male and female swell immediately preceding and during the mating season. Male ruffed lemurs will engage a prospective mate with a panoply of head-bobbing, calls, scent-marking and other displays, sometimes in concert with "roar-shrieking" and physical-contact initiation by the female. In the unlikely event you are observing maternal behaviors in the lemurs' natural Madagascar woodlands, you might observe female red ruffed lemurs assembling nests from vegetation and moss, and later transporting their young offspring in their jaws. Other behavioral differences may be subtle. A 2002 study by researcher Natalie Vasey showed that female red ruffed lemurs tended to favor younger leaves and flowers than males during the dry season and the reproductive cycle.
Tags: ruffed lemurs, female ruffed, male female, pounds with, pounds with range