First we share an early clip taken from a male ringtailed lemur (Lemur catta), "Licinius", as he is fed by an experimenter, navigates about and visually explores his enclosure, and observes his male brown lemur (Eulemur fulvus) cagemate, "Maurice". The camera shows the view available in front of the subject lemur's head, and the red path illustrates where the subject is looking during each frame. Other categories of interest are marked in green (lemurs), blue (humans), magenta (environmental anchors), or yellow (food reward).
active reward and locomotion 64sec AVI, 15MB.

We next show two clips illustrating social fixations and locomotor behavior in the male ringtailed lemur "Aracus", sharing an indoor-outdoor enclosure with three females. The lemur viewed through the enclosure wall is a rival male. In this particular demonstration we have marked the lemur subject's point-of-regard in red, and the head and tailbase of follow lemurs in blue. We have stabilized the first (stationary) clip with respect to the external environment.
social attention, stabilized 9sec AVI, 3.1MB
social and locomotor attention 34sec AVI, 19MB

In this clip, Aracus is in a large outdoor enclosure and is interacting with a rival male. The rival male waves his tail in the manner typical of "stinkfights" over mating access: by stroking his tail with his wrist glands he coats it in his scent. Aracus's scanpath is illustrated in red, while the rival male is marked in blue. Aracus, dominant but encumbered, looks between his rival and means of escape, but ultimately drives off his opponent.
agonistic encounter 31sec AVI, 13MB

Here Aracus shares the indoor portion of his indoor-outdoor enclosure with a female. Both lemurs explore similar areas of the visual scene, Aracus sometimes following and sometimes leading. Aracus's scanpath is illustrated in red, environmental anchors are marked in blue, and the female lemur has been left unmarked for clarity.
co-orienting, stabilized 13sec AVI, 3.2MB

For more information, please see:

"Noninvasive telemetric gaze tracking in freely-moving socially-housed prosimian primates."
Shepherd SV, Platt ML.
Methods 38(3):185-194, 2006.
[reprint]&[Skriatok scripts for Matlab]

"Spontaneous social orienting and gaze-following in ringtailed lemurs (Lemur catta)."
Shepherd SV, Platt ML.
Animal Cognition 11(1):13-20, 2008.
[reprint&supp]