Llamas use social information from conspecifics and humans to solve a spatial detour task

Abstract

Learning by observing others (i.e. social learning) is an important mechanism to reduce the costs of individual learning. Social learning can occur between conspecifics but also heterospecifics. Domestication processes might have changed the animals' sensitivity to human social cues and recent research indicates that domesticated species are particularly good in learning socially from humans. Llamas (Lama glama) are an interesting model species for that purpose. Llamas were bred as pack animals, which requires close contact and cooperative behaviour towards humans. We investigated whether llamas learn socially from trained conspecifics and humans in a spatial detour task. Subjects were required to detour metal hurdles arranged in a V-shape to reach a food reward. Llamas were more successful in solving the task after both a human and a conspecific demonstrated the task compared to a control condition with no demonstrator. Individual differences in behaviour (i.e. food motivation and distraction) further affected the success rate. Animals did not necessarily use the same route as the demonstrators, thus, indicating that they adopted a more general detour behaviour. These results suggest that llamas can extract information from conspecific and heterospecific demonstrations; hence, broadening our knowledge of domesticated species that are sensitive to human social behaviour.

Keywords: Domestication; Emulation; Human demonstration; New world camelids; Social learning; Stimulus enhancement.

Fig. 1

Experimental arena (approx. 8 × 10 m) with V-shaped metal hurdles. The animal is depicted at the starting point (a). The food reward is placed in the purple bowl behind the hurdle.

Fig. 2

Proportion of successful trials per test condition. The coloured lines show the model estimates and the whiskers the confidence intervals. Points represent individual data

Fig. 3

Latency to reach the food bowl across trials, plotted separately for each test group. Transparent points indicate raw individual data. Bold points and lines depict mean per group and error bars indicate the confidence limits for the mean. Note that for two individuals the data from the first trial was excluded because they reached the food bowl by inserting their head into the hurdles

Fig. 4

Proportion of distraction behaviours per test group. Points indicate raw data, coloured bars show medians, and boxes depict interquartile range. Coloured lines indicated model estimates and whiskers show confidence intervals