Department of Psychology, Princeton University, Princeton, New Jersey, United States of America.
Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey, United States of America.
PLoS Comput Biol. 2022 Jun 13;18(6):e1010173. doi: 10.1371/journal.pcbi.1010173. eCollection 2022 Jun.
Evolution and development are typically characterized as the outcomes of gradual changes, but sometimes (states of equilibrium can be punctuated by sudden change. Here, we studied the early vocal development of three different mammals: common marmoset monkeys, Egyptian fruit bats, and humans. Consistent with the notion of punctuated equilibria, we found that all three species undergo at least one sudden transition in the acoustics of their developing vocalizations. To understand the mechanism, we modeled different developmental landscapes. We found that the transition was best described as a shift in the balance of two vocalization landscapes. We show that the natural dynamics of these two landscapes are consistent with the dynamics of energy expenditure and information transmission. By using them as constraints for each species, we predicted the differences in transition timing from immature to mature vocalizations. Using marmoset monkeys, we were able to manipulate both infant energy expenditure (vocalizing in an environment with lighter air) and information transmission (closed-loop contingent parental vocal playback). These experiments support the importance of energy and information in leading to punctuated equilibrium states of vocal development.
进化和发展通常被描述为渐进变化的结果，但有时（平衡状态也可能被突然的变化所打断。在这里，我们研究了三种不同哺乳动物的早期发声发育：普通狨猴、埃及果蝠和人类。与间断平衡的观点一致，我们发现这三个物种在其发育发声的声学特性上至少经历了一次突然的转变。为了理解这种机制，我们构建了不同的发育景观模型。我们发现，这种转变最好被描述为两种发声景观之间平衡的转移。我们表明，这两个景观的自然动态与能量消耗和信息传递的动态一致。通过将它们用作每个物种的约束条件，我们预测了从不成熟到成熟发声的转变时间的差异。使用狨猴，我们能够同时操纵婴儿的能量消耗（在较轻的空气中发声）和信息传递（闭环条件性父母发声回放）。这些实验支持了能量和信息在导致发声发育的间断平衡状态中的重要性。
