Altruistic food giving among genetically unrelated individuals is rare in nature. The few examples that exist suggest that when animals give food to unrelated others, they may do so on the basis of mutualistic or reciprocally altruistic relationships. We present the results of four experiments designed to tease apart the factors mediating food giving among genetically unrelated cotton-top tamar...

Comparing forelimb use across primates can improve the understanding of the mechanisms and functions of brain asymmetry. We broadened the comparative framework by investigating hand use biases across spontaneous behaviors in 11 captive emperor tamarins of 2 family groups. We found a right preference across 58% of pooled unimanual bouts and 60% of all tasks. The maximum biases for a single task ...

A number of recent studies on the learning of invented patterns in symbol sequences by animals such as cottontop tamarins (Hauser, Chomsky & Fitch 2002:1578; Fitch & Hauser 2004; Hauser 2005; O’Donnell, Hauser & Fitch 2005), songbirds (Gentner 2005), and undergraduates (Fitch & Hauser 2004; Perruchet & Rey, in press) have shown interest in the contrast between two classes of sets of strings: th...