E is not available. In other words, participants would be instructed to produce all of their gestures in the space immediately in front of the torso, without having the option to locate some nominal gestures on either side, with action gestures going from one side to the other. This manipulation would place the entire interpretive burden on linear order, and could very well influence constituent order preferences in production. Such a study could be a helpful complement to Langus and Nespor’s (2010) fourth experiment, which is a non-spatial comprehension task in the auditory modality, using words from spoken language.NIH-PA Author IRC-022493 site Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptCogn Sci. Author manuscript; available in PMC 2015 June 01.Hall et al.PageThe second difference between our laboratory contexts and attested patterns of natural 11-Deoxojervine site language evolution and change in the world is that our experiments were explicitly designed to probe the cognitive preferences that influence communication from a production standpoint only. However, natural systems are doubtless influenced by constraints on comprehension and acquisition as well, which could slow the pace of change. For example, it could be that the orders that are easiest to produce are different from the orders that are easiest to understand. (Hall, Ferreira, Mayberry, submitted, report evidence suggesting that this may indeed be the case.) This would then require systems to evolve some sort of compromise between these competing pressures. From an acquisition standpoint, successful acquisition implies the faithful reproduction of the patterns in the input. Therefore, at least some aspects of the acquisition process actively work against other pressures that might pressure a learner to inject change into the system. This hypothesis could be tested by having participants act not just as producers in the lab, but also as learners and comprehenders. We would then expect to see attenuation of the effects in our present data. The differences discussed above highlight the potential role of modality (i.e., vocal or manual) in influencing constituent order preferences. This is especially critical since our two main sources of information about word order (studies of homesign/emerging sign languages and large-scale typological surveys of spoken languages) focus on different modalities. It will likely be important to characterize which pressures are invariant across modalities, and which appear to be stronger constraints on one modality than another. Fedzechkina, Jaeger, and Newport (2013) have recently supplied evidence from an artificial (spoken) language learning paradigm showing that adult language learners are sensitive to the relationship between semantic reversibility and case marking. As we observed in pantomime, participants in their study avoided using unmarked SOV (and OSV) utterances to describe reversible events in the spoken modality. Although their participants did not use SVO as an alternative, this may be because (a) case marking was provided as an alternative cue to argument structure, and (b) both SOV and OSV order were explicitly modeled for the participants, whereas SVO was not. Future work could address whether a shift to SVO might also happen in the spoken modality if either or both of those cues were absent. Conclusions In sum, we suggest that the distribution of constituent orders across the world’s languages, both synchronically and diachronically, likely re.E is not available. In other words, participants would be instructed to produce all of their gestures in the space immediately in front of the torso, without having the option to locate some nominal gestures on either side, with action gestures going from one side to the other. This manipulation would place the entire interpretive burden on linear order, and could very well influence constituent order preferences in production. Such a study could be a helpful complement to Langus and Nespor’s (2010) fourth experiment, which is a non-spatial comprehension task in the auditory modality, using words from spoken language.NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptCogn Sci. Author manuscript; available in PMC 2015 June 01.Hall et al.PageThe second difference between our laboratory contexts and attested patterns of natural language evolution and change in the world is that our experiments were explicitly designed to probe the cognitive preferences that influence communication from a production standpoint only. However, natural systems are doubtless influenced by constraints on comprehension and acquisition as well, which could slow the pace of change. For example, it could be that the orders that are easiest to produce are different from the orders that are easiest to understand. (Hall, Ferreira, Mayberry, submitted, report evidence suggesting that this may indeed be the case.) This would then require systems to evolve some sort of compromise between these competing pressures. From an acquisition standpoint, successful acquisition implies the faithful reproduction of the patterns in the input. Therefore, at least some aspects of the acquisition process actively work against other pressures that might pressure a learner to inject change into the system. This hypothesis could be tested by having participants act not just as producers in the lab, but also as learners and comprehenders. We would then expect to see attenuation of the effects in our present data. The differences discussed above highlight the potential role of modality (i.e., vocal or manual) in influencing constituent order preferences. This is especially critical since our two main sources of information about word order (studies of homesign/emerging sign languages and large-scale typological surveys of spoken languages) focus on different modalities. It will likely be important to characterize which pressures are invariant across modalities, and which appear to be stronger constraints on one modality than another. Fedzechkina, Jaeger, and Newport (2013) have recently supplied evidence from an artificial (spoken) language learning paradigm showing that adult language learners are sensitive to the relationship between semantic reversibility and case marking. As we observed in pantomime, participants in their study avoided using unmarked SOV (and OSV) utterances to describe reversible events in the spoken modality. Although their participants did not use SVO as an alternative, this may be because (a) case marking was provided as an alternative cue to argument structure, and (b) both SOV and OSV order were explicitly modeled for the participants, whereas SVO was not. Future work could address whether a shift to SVO might also happen in the spoken modality if either or both of those cues were absent. Conclusions In sum, we suggest that the distribution of constituent orders across the world’s languages, both synchronically and diachronically, likely re.