Social foraging in marmoset monkeys and the question of intelligence

Abstract

A social group of five saddle-back tamarins ( Saguinus fuscicollis ) were allowed 15 min per day in a sizeable room adjacent to their home cage. Every other day two additional novel test objects were placed in the room; one contained food on first presentation, and the next day the locations of both were sometimes moved. From the outset, and even when there were 30 objects to choose from, the animals were acute in detecting the novel objects and in remembering the objects and the locations in which they had found food. Whichever individuals had eaten first were among the first to approach the next day. Subsequent tests showed that such one-trial learning was not dependent on object-novelty; that the animals probably remembered all 30 objects and the location of each; and that they spontaneously performed what amounts to generalized delayed matching to sample. The data match or surpass the asymptotic performances of other marmosets on, for example, learning set tasks but are consistent with what is known about the foraging habits of wild S. fuscicollis. Optim al foraging theory is less likely to be an overestimate of animals’ mental capacities than previous studies are an underestimate.

Colour Discrimination in the Black-Tufted-Ear Marmoset (Callithrix penicillata): Ecological Implications

“…fruits and insects) [Morgan et al, 1992] and trichromatic advantages for detecting conspicuous fruits [Mollon, 1989;Caine and Mundy, 2000;Smith et al, 2003]. In fact, callitrichids live in small family groups [Sussman and Kinzey, 1984] and forage as a team [Menzel and Juno, 1985]. Therefore, if there are complemen-tary advantages to dichromacy and trichromacy, co-operative foraging could be responsible for the maintenance, by kin selection, of the visual polymorphism found in the New World monkeys [Tovée et al, 1992].…”

A socioecological perspective on primate cognition, past and present

“…Spatial memory is widespread among mammals, and is shared by most, if not all, primates (e.g., Garber and Hannon 1993;Gibeault and MacDonald 2000;Janson 1998;MacDonald and Wilkie 1990;Menzel and Juno 1985;Platt et al 1996). Although little is known about the role of olfaction in primate ecology [but see Dominy et al (2001) and Heymann (2006) for reviews of what is known], lemurs appear to use visual cues to remember the locations of parked infants, sleeping nests, and feeding sites (Kappeler 2000).…”

Editorial Commentary

“…Marsh tits are remarkably effective at finding their food hoards (Shettleworth & Krebs 1982). Socially foraging marmosets display remarkable one-trial learning (Menzel & Juno 1985). Such demonstrations need not be treated as a challenge to generalprocess learning theory but suggest predispositions in the application of learning processes to ecologically relevant situations in ways more complex than those suggested by Macphail.…”

“…The songbird's capacity for song-learning and the human propensity for language acquisition Macphail sets aside as specialized devices, not elusive general intelligence. The titi monkey's deliberate deciphering of shortcuts, which is clearly related to its stealthy, cryptic life style in fear of predators, and the saddle-backed tamarin's readiness to remember the clues to concealed food, which probably relates to its small, dispersed food sources in the wild, Macphail would likewise dismiss as peripheral motivational factors (Fragaszy 1981;Menzel 1982;Terborgh 1983). The chimpanzee's political subtlety (de Waal 1982;Goodall 1986; press; Whiten & Bryne, in press) would merely be an aspect of its giddy social whirl.…”