An agent-based model clarifies the importance of functional and developmental integration in shaping brain evolution
An agent-based model clarifies the importance of functional and developmental integration in shaping brain evolution
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基于主体的模型阐明了功能和发育整合在塑造大脑进化中的重要性
DOI：
10.1101/2020.05.04.075820
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Avin S
中科院分区：
文献类型：
--
作者：
Avin S
脊椎动物大脑结构的特征不仅是各组成部分之间比例的相对一致性，而且还有许多与这些一般趋势背道而驰的例子。另一种假说通过强调“外部”过程，如协调或发散选择，或“内部”过程，如大脑各区域之间的发育耦合，来解释这些模式。虽然这些假设并不是相互排斥的，但对于它们随时间的相对重要性，或者这种重要性如何在进化环境中发生变化，几乎没有达成一致。结果我们引入了一个基于代理的模型，来模拟一个基本系统中的大脑进化，并检查影响大脑进化的变量之间的依赖关系。我们发现，大脑进化的“协同”模式本身并不能提供发育耦合的证据，尽管这些术语在文献中经常被视为同义词。相反，协同进化既可以反映功能整合，也可以反映发展整合。我们的模型进一步允许我们阐明这种发育耦合或解偶联具有潜在适应性的条件，揭示了在神经进化中维持这两种机制的支持。重要的是，我们说明了偏离协调进化的概率是如何依赖于神经组织的成本/收益比的，当整体大脑大小受到限制时，神经组织的成本/收益比会增加。结论我们得出结论，发育耦合和非耦合的大脑结构都可以提供适应机制，这取决于选择在大脑结构、生活史和神经组织成本上的分布。然而，当限制也作用于大脑的整体大小时，大脑结构选择的异质性将有利于特定区域或镶嵌的进化。无论如何，发育耦合和非耦合大脑结构的各自优势意味着两者都可能在波动的环境中持续存在。这意味着，发育耦合不太可能是一个持久的制约因素，但可能会演变为选择以维持功能整合的适应性结果。
BackgroundVertebrate brain structure is characterised not only by relative consistency in scaling between components, but also by many examples of divergence from these general trends.. Alternative hypotheses explain these patterns by emphasising either ‘external’ processes, such as coordinated or divergent selection, or ‘internal’ processes, like developmental coupling among brain regions. Although these hypotheses are not mutually exclusive, there is little agreement over their relative importance across time or how that importance may vary across evolutionary contexts.ResultsWe introduce an agent-based model to simulate brain evolution in a ‘bare-bones’ system and examine dependencies between variables shaping brain evolution. We show that ‘concerted’ patterns of brain evolution do not, in themselves, provide evidence for developmental coupling, despite these terms often being treated as synonymous in the literature. Instead, concerted evolution can reflect either functional or developmental integration. Our model further allows us to clarify conditions under which such developmental coupling, or uncoupling, is potentially adaptive, revealing support for the maintenance of both mechanisms in neural evolution. Critically, we illustrate how the probability of deviation from concerted evolution depends on the cost/benefit ratio of neural tissue, which increases when overall brain size is itself under constraint.ConclusionsWe conclude that both developmentally coupled and uncoupled brain architectures can provide adaptive mechanisms, depending on the distribution of selection across brain structures, life history and costs of neural tissue. However, when constraints also act on overall brain size, heterogeneity in selection across brain structures will favour region specific, or mosaic, evolution. Regardless, the respective advantages of developmentally coupled and uncoupled brain architectures mean that both may persist in fluctuating environments. This implies that developmental coupling is unlikely to be a persistent constraint, but could evolve as an adaptive outcome to selection to maintain functional integration.
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影响因子：
9.2
作者：
Kimberley V. Sukhum;Jerry Shen;B. Carlson
通讯作者：
B. Carlson
影响因子：
0.6
作者：
Currie, Adrian
通讯作者：
Currie, Adrian
DOI：
10.1159/000341161
发表时间：
2012-08
期刊：
Brain, Behavior and Evolution
影响因子：
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作者：
B. Powell;M. Leal
通讯作者：
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DOI：
10.1098/rspb.2019.1608
发表时间：
2019
期刊：
bioRxiv
影响因子：
--
作者：
Lauren E. Powell;Sally E. Street;R. Barton
通讯作者：
R. Barton
数据来自：人工选择相对大脑大小期间大脑区域体积的演变
影响因子：
64.8
作者：
Kotrschal Alexander;Zeng Hong;van der Bijl Wouter;Oehman;Kotrschal Kurt;Pelckmans Kristiaan;Kolm Niclas
通讯作者：
Kolm Niclas