TASIERS.
A nocturnal animals, the tarsier has two enormous eyes each as large as its brain. Unlike other nocturnal mammals, however, tarsier eyes do not contain tapetum lucidum which reflects light from the back of the eye for a second exposure on the retina to maximize light capture. From this we can infer that the common ancestor of all haplorrhine must have been a diurnal animal which shed the tapetum lucidum to eliminate blurry images caused by reflected light. When the tarsier became a nocturnal animal, it enlarged its eyes to compensate for the lack of tapetum lucidum.