The reptiles were thus among the first serious predators mammals faced. Today, the only other threats faced by primates are raptors, such as eagles and hawks, and large carnivores, such as bears, large cats and wolves, but these animals evolved long after snakes. Furthermore, these other predators can be safely detected from a distance.
For snakes, the opposite is true. Early snakes killed their prey using surprise attacks and by suffocating them to death—the method of boa constrictors. But the improved vision of primates, combined with other snake-coping strategies developed by other animals, forced snakes to evolve a new weapon: venom. This important milestone in snake evolution occurred about 60 million years ago.
Once primates developed specialized vision and enlarged brains , these traits became useful for other purposes, such as social interactions in groups. Isbell's new theory could explain how a number of primate-defining traits evolved. For example, primates are among the few animals whose eyes face forward most animals have eyes located on the sides of their heads. This so-called "orbital convergence" improves depth perception and allows monkeys and apes, including humans, to see in three dimensions.
Primates also have better color vision than most animals and are also unique in relying heavily on vision when reaching and grasping for objects.
One of the most popular ideas for explaining how these traits evolved is called the "visual predation hypothesis. Another popular idea, called the "leaping hypothesis," argues that orbital convergence is not only important for 3D vision, but also for breaking through camouflage. Thus, it would have been useful not only for capturing insects and finding small fruits, but also for aiming at small, hard-to-see branches during mid-leaps through trees.
First, there is no solid evidence that early primates were committed insectivores. It's possible that like many primates today, they were generalists, eating a variety of plant foods, such as leaves, fruit and nectar, as well as insects. More importantly, recent neuroscience studies do not support the idea that vision evolved alongside the ability to reach and grasp.
Rather, the data suggest that the reaching-and-grasping abilities of primates actually evolved before they learned to leap and before they developed stereoscopic, or 3D, vision. Isbell thinks proto-primates—the early mammals that eventually evolved into primates—were in better position compared to other mammals to evolve specialized vision and enlarged brains because of the foods they ate. Rhesus macaques Macaca mulatta use snake posture to assess level of threat.
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Factors increasing snake detection and perceived threat in captive rhesus macaques Macaca mulatta. American Journal of Primatology Linking social and pathogen transmission networks using microbial genetics in giraffe Giraffa camelopardalis. Journal of Animal Ecology Maternal investment and infant survival in gray-cheeked mangabeys Lophocebus albigena. Pulvinar neurons reveal neurobiological evidence of past selection for rapid detection of snakes. Proceedings of the National Academy of Sciences Correlations between social context and fecal glucocorticoid metabolite concentrations in free-ranging female gray-cheeked mangabeys Lophocebus albigena in Kibale National Park, Uganda.
Folia Biologica Erythrocebus patas Patas monkey. In The Mammals of Africa: Vol. II Primates T. Butynski, J. Kingdon, and J. Kalina, eds. Bloomsbury Publishing, London, pp. Chlorocebus pygerythrus Vervet monkey. Nutritional benefits of Crematogaster mimosae ants and Acacia drepanolobium gum for patas monkeys and vervets in Laikipia, Kenya.
Stag parties linger: continued gender bias in a female-rich scientific discipline. Re-evaluating the Ecological Constraints model with red colobus monkeys Procolobus rufomitratus tephrosceles. Bunce, J. Color vision variation and foraging behavior in wild Neotropical titi monkeys Callicebus brunneus : possible mediating roles for spatial memory and reproductive status.
International Journal of Primatology — Adiseshan, A. Affiliative relationships and reciprocity among adult male bonnet macaques Macaca radiata at Arunachala Hill, India.
Beisner, B. Factors affecting aggression among females in captive groups of rhesus macaques Macaca mulatta. Arlet, A. Social factors increase fecal testosterone levels in wild male gray-cheeked mangabeys Lophocebus albigena. Hormones and Behavior Characterization of opsin gene alleles affecting color vision in a wild population of titi monkeys Callicebus brunneus. Jaffe, K.
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Ranging and social behavior after a predator-induced group fusion in wild vervet monkeys Cercopithecus aethiops in Laikipia, Kenya. The guenons: polyspecific associations in socioecological perspective. In Primates in Perspective, 2nd Edition C. Campbell, A.
Fuentes, K. MacKinnon, S. Bearder, and R. Stumpf, eds. Oxford University Press, New York, pp. Harvard University Press, New York. Chancellor, R.
Female grooming markets in a population of gray-cheeked mangabeys Lophocebus albigena. After the fire: benefits of reduced ground cover for vervet monkeys Cercopithecus aethiops.
Variation in behavioral and hormonal responses of adult male gray-cheeked mangabey Lophocebus albigena to crowned eagles Stephanoaetus coronatus in Kibale National Park, Uganda. Behavioral Ecology and Sociobiology Pinter-Wollman, N. Assessing translocation outcome: comparing behavioral and physiological aspects of translocated and resident African elephants Loxodonta africana.
Demography and life histories of sympatric patas monkeys Erythrocebus patas and vervets Cercopithecus aethiops in Laikipia, Kenya. Schoof, V. What traits promote male parallel dispersal in primates? Jack, K.
Lynne A. Isbell
Dispersal in primates: advancing an individualized approach. The relationship between social behavior and habitat familiarity in African elephants Loxodonta africana. Proceedings of the Royal Society B Reproductive tactics influence cortisol levels in individual male gray-cheeked mangabeys Lophocebus albigena.
Dispersal in Primates. De Jong, Y. Decline of the geographical range of the southern patas monkey Eythrocebus patas baumstarki in Tanzania. Oryx Ground substrate affects activity budgets and hair loss in captive outdoor-housed rhesus macaques Macaca mulatta. Off, E. Population density and habitat preferences of the Kenya lesser galago Galago senegalensis braccatus Elliot, along the Ewaso Nyiro River, Kenya.
Journal of East African Natural History Punishment and competition over food in captive rhesus macaques Macaca mulatta. Animal Behaviour
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