Humans stand alone in terms of their potential to collectively and cumulatively change their culture in an open-ended manner. This open-endedness provides societies with the ability to continually expand their resources and to increase their capacity to store, transmit and process information at a collective-level. Here, we propose that the production of resources arises from the interaction between cultural systems (a society's repertoire of interdependent techniques, artifacts, norms and knowledge) and search spaces (an ensemble of needs, problems and goals facing a society). Starting from this premise we develop a macro-level model wherein both cultural systems and search spaces are subject to evolutionary dynamics. By manipulating the extent to which these dynamics are characterised by stochastic or selection-like processes, we demonstrate that open-ended growth is extremely rare, historically contingent and only possible when cultural systems and search spaces co-evolve. Here, stochastic factors must be strong enough to continually perturb the dynamics into a far-from-equilibrium state, whereas selection-like factors help maintain effectiveness and ensure the sustained production of resources. Only when this co-evolutionary dynamic maintains effective cultural systems, supports the ongoing expansion of the search space and leads to an increased provision of resources do we observe open-ended cultural evolution.

翻译：人类在集体且累积性地以开放方式改变其文化方面的潜力是独一无二的。这种开放性使社会能够持续扩展其资源，并在集体层面提高存储、传递和处理信息的能力。本文提出，资源的产生源于文化系统（一个社会相互依存的技术、人工制品、规范与知识的总和）与搜索空间（社会所面临的需求、问题与目标的集合）之间的相互作用。基于这一前提，我们构建了一个宏观模型，其中文化系统与搜索空间均受演化动力学支配。通过调控这些动力学过程中随机性过程与类选择过程的相对强度，我们证明开放式的增长极为罕见，具有历史偶然性，且仅当文化系统与搜索空间协同演化时才可能实现。在此过程中，随机性因素必须足够强以持续扰动系统至远离平衡态，而类选择因素则有助于维持有效性并确保资源的持续产生。只有当这种协同演化动态能够维持有效的文化系统、支持搜索空间的持续扩展并带来资源供给的增长时，我们才能观察到开放式的文化演化。