The set of concepts communicated by participants in [21].

<p>Distractor items are given in italic.</p

Mean response latency (msec) for Initial and Late 2-Person (red bars) and 8-Person (blue bars) signs.

<p>Error bars indicate the standard error of the means.</p

Mean percent egocentric communication by each participant when their personal shape descriptions were perceived to be more informative than their addressee’s shape descriptions (Personal Superior), when the shape descriptions were perceived to be equally informative (Descriptions Equal) and when the addressee’s shape descriptions were perceived to be more informative than their personal shape descriptions (Addressee Superior).

<p> Error bars are bootstrapped 95% confidence intervals.</p

Mean percent of trials participants in the Unknown- and Known-Addressee conditions employed the different communication strategies.

<p>Mean percent of trials participants in the Unknown- and Known-Addressee conditions employed the different communication strategies.</p

Mean reproduction fidelity (on a rating scale from 0–9, where 0 = very dissimilar and 9 = very similar) of Initial and Late 2-Person (red bars) and 8-Person (blue bars) signs.

<p>Error bars indicate the standard error of the means.</p

Sign refinement and alignment for the item <i>Theatre</i> across six games between a 2-Person group playing the Pictionary-like task (sampled from the corpus collected by [21]).

<p>Participants alternate drawing and identifying roles from game to game.</p

Sign refinement and alignment for the item <i>Museum</i> among members of an 8-Person group playing the Pictionary-like task (sampled from the corpus collected by [21]).

<p>Participants interact with each of the other members of their group (Partner 1–7). Drawings are sampled from Game 1 and Game 2 for each interacting pair (Game 1 drawings are presented on the left for each Pair). Shading is used to discriminate the different participant pairings.</p

Mean time (msec) taken to produce Initial and Late 2-Person (red bars) and 8-Person (blue bars) signs.

<p>Error bars indicate the standard error of the means.</p

Abstract geometric shapes described by participants in Experiment 1 and 2 (shapes sampled from [17]).

<p>Abstract geometric shapes described by participants in Experiment 1 and 2 (shapes sampled from [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0159570#pone.0159570.ref017" target="_blank">17</a>]).</p

Naïve participants' comprehension (% correctly identified) of descriptions produced under the different conditions of Experiment 1 and Experiment 2.

<p>Error bars indicate the standard errors of the means.</p