Effects of activity pattern on eye size and orbital aperture size in primates.
نویسنده
چکیده
Among primates, nocturnal species exhibit relatively larger orbital apertures than diurnal species. Most researchers have considered this disparity in orbital aperture size to reflect differences in eye size, with nocturnal primates having relatively large eyes in order to maximize visual sensitivity. Presumed changes in eye size due to shifts in activity pattern are an integral part of theoretical explanations for many derived features of anthropoids, including highly convergent orbits and a postorbital septum. Here I show that despite clear differences in relative orbital aperture size, many diurnal and nocturnal primates do not differ in relative eye size. Among nocturnal primates, relative eye size is influenced by diet. Nocturnal visual predators (e.g., Tarsius, Loris, and Galago moholi) tend to have larger relative eye sizes than diurnal primates. By contrast, nocturnal frugivores (e.g., Perodicticus, Nycticebus, and Cheirogaleus) have relative eye sizes that are comparable to those of diurnal primates. Although some variation in orbital aperture size can be attributed to variation in eye size, both cornea size and orbit orientation also exert a strong influence on orbital aperture size. These findings argue for caution in the use of relative orbital aperture size as an indicator of activity pattern in fossil primates. These findings further suggest that existing scenarios for the evolution of unique orbital morphologies in anthropoids must be modified to reflect the importance of ecological variables other than activity pattern.
منابع مشابه
Eye Size at Birth in Prosimian Primates: Life History Correlates and Growth Patterns
BACKGROUND Primates have large eyes relative to head size, which profoundly influence the ontogenetic emergence of facial form. However, growth of the primate eye is only understood in a narrow taxonomic perspective, with information biased toward anthropoids. METHODOLOGY/PRINCIPAL FINDINGS We measured eye and bony orbit size in perinatal prosimian primates (17 strepsirrhine taxa and Tarsius ...
متن کاملEffects of Laser Physical Parameters on Lesion Size in Retinal Photocoagulation Surgery: Clinical OCT and Experimental Study
Introduction: The aim of the present study was to determine burn intensity in retinal laser photocoagulation based on laser parameters; wavelength, power, beam size and pulse duration, using Optical Coherence Tomography (OCT), fundus camera, physical eye model and computer simulation in a clinical study.Materials and Methods: Participants were 10 adult patients between 50-80 years with prolifer...
متن کاملHistopathologic Changes of Extraocular Mus-cle Fibers after Injection of Botulinum Toxin
Background: Use of botulinum toxin is becoming a popular way in treatment of some forms of strabismus.To evaluate the morphological changes in the orbital surface layer muscles of the rabbit eye following a single injection of botulinum toxin. Methods: 10 white Dutch rabbits weighing 2–3 kg received either 10 units (group 1; n=5) or 20 units (group 2; n=5) of botulinum toxin into the superior r...
متن کاملEffect of Geogrid Aperture Size and Soil Particle Size on Geogrid-Soil Interaction under Pull-Out Loading
متن کامل
The Effect of Aperture Size on the Cavity Performance of Solar Thermoelectric Generator
In this manuscript, a solar cavity packed with thermoelectric generator modules is investigated numerically. The hot plate of TEG modules make the inner surface of the cube, and the cold plate is outside of the cavity, under natural convection. The TEG modules are electrically in series. The solution algorithm using the equations of heat transfer and generated power of TEG modules is d...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of human evolution
دوره 51 2 شماره
صفحات -
تاریخ انتشار 2006