Bull L, Fogarty T C
Faculty of Computer Studies and Mathematics, University of the West of England, Bristol,
Artif Life. 1995 Spring;2(3):269-92. doi: 10.1162/artl.1995.2.3.269.
Symbiosis is the phenomenon in which organisms of different species live together in close association, resulting in a raised level of fitness for one or more of the organisms. Symbiogenesis is the name given to the process by which symbiotic partners combine and unify-forming endosymbioses and then potentially transferring genetic material-giving rise to new morphologies and physiologies evolutionarily more advanced than their constitutents. In this article we begin by using the NKC model of coevolution to examine endosymbiosis and its effect on the evolutionary performance of the partners involved. We are then able to suggest the conditions under which endosymbioses are more likely to occur and why; we find they emerge between organisms within a window of their respective "chaotic gas regimes" and hence that the association represents a more stable state for the partners. The conditions under which gene transfer is more likely to represent an advantage for such endosymbionts are then examined within the same model. We find that, providing a suitable pathway exists, such a process can lead to a more efficient genetic configuration for the symbionts within a window that overlaps that in which endosymbioses occur. Finally, the results are used as grounds for implementing symbiogenesis within artificial evolutionary multiagent systems.
共生是指不同物种的生物体紧密联系、共同生活的现象，这会使其中一个或多个生物体的适应度提高。共生起源是指共生伙伴结合并统一形成内共生体，然后可能转移遗传物质，从而产生在进化上比其组成部分更高级的新形态和生理特征的过程。在本文中，我们首先使用共同进化的NKC模型来研究内共生及其对相关伙伴进化表现的影响。然后，我们能够提出内共生更可能发生的条件及其原因；我们发现它们出现在各自“混沌气体状态”范围内的生物体之间，因此这种关联对伙伴来说代表着一种更稳定的状态。然后在同一模型中研究基因转移更可能成为此类内共生体优势的条件。我们发现，只要存在合适的途径，这样的过程可以在与内共生发生范围重叠的一个范围内为共生体带来更有效的基因配置。最后，这些结果被用作在人工进化多智能体系统中实现共生起源的依据。
