Examples of biological rhythmicity mounted in the first half of the twentieth century, but the nature of biological rhythms – whether they were direct responses to rhythmic environmental stimuli or generated internally by biological clocks or oscillators – remained sharply disputed. When Frank A. Brown Jr. observed precise twenty-four-hour rhythms in the colour changes of fiddler crabs that were isolated from changes in environmental lighting that could synchronise them with the daily cycle, he rejected the internal clock as an explanation, owing to his belief that such a biological mechanism must operate chemically and consequently run faster at higher temperatures (Van’t Hoff’s rule), which was not borne out by his experiments. Colin Pittendrigh was committed to the idea that the rhythms were generated by unknown, temperature-compensated mechanisms, without offering any explanation for how this might be accomplished. At the core of their dispute, which was aired publicly from 1954 until Brown’s death in 1983, was a difference in belief: Brown’s fundamental reductionism, which required biological processes to conform to the laws of chemistry, vs. Pittendrigh’s trust in the power of evolution to select for such a temperature compensated biological clock, for which no plausible chemical model then existed.

中文翻译：

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生物钟争论中的化学范式与生物范式

生物节律的例子出现在 20 世纪上半叶，但生物节律的性质——无论它们是对有节奏的环境刺激的直接反应，还是由生物钟或振荡器在内部产生——仍然存在很大争议。当 Frank A. Brown Jr. 观察到招潮蟹颜色变化中精确的 24 小时节律时，这些变化与环境照明的变化无关，可以使它们与日常周期同步，他拒绝将内部时钟作为解释，因为他相信这种生物机制必须以化学方式运作，因此在更高的温度下运行得更快（范特霍夫法则），但他的实验并未证实这一点。Colin Pittendrigh 致力于认为节奏是由未知的，温度补偿机制，但没有对如何实现这一点提供任何解释。从 1954 年到布朗于 1983 年去世，他们争论的核心是信念的不同：布朗的基本还原论要求生物过程符合化学定律，而皮滕德里则相信进化的力量选择这样一个温度补偿的生物钟，当时不存在合理的化学模型。