Seasonal and Latitudinal Adaptations in the Life Cycles of Crickets
Seasonal and Latitudinal Adaptations in the Life Cycles of Crickets
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蟋蟀生命周期中的季节和纬度适应
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发表时间：
1978
期刊：
影响因子：
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通讯作者：
Sinzo Masaki
中科院分区：
文献类型：
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作者：
Sinzo Masaki
与季节变化相关的序列，每个物种的个体生命周期或多或少是同步的。在北纬30°以北的日本列岛主要地区栖息的物种中，只有Gryllodes sigiulatus 和Myrmecophilus sapporoensis 可以在全年的不同阶段被发现。这些特殊物种被限制在特殊的栖息地，分别免受天气条件、房屋和蚁巢剧烈波动的影响，这一事实表明，适应温带气候需要有明确的季节性生命周期模式。当然，后者是由于在生命周期中存在一个特定阶段，对长期发展停滞具有很强的抵抗力。因此，对环境中广泛的季节性波动的适应不是通过普遍增加耐受范围来实现的，而是通过将发育周期生理划分为具有不同最佳温度的活跃和滞育阶段来实现，大致分别对应于夏季和冬季条件（Browning，1952a，b；Hogan，1960a，b；Masaki，1960，1962，1963，1965；拉克什帕尔，1962a、b、c，1964）。从分配原则来看（Levins，1968），这种专业化似乎对温带气候具有更高的适应性。它使蟋蟀能够在滞育阶段跳过严酷的季节，而不妨碍活跃阶段对有利季节的适应。繁殖活动的同步化可能是这一进化路线的另一个推动力，或者仅仅是季节性发展的应有结果。如果将适当的季节提示纳入将生理状态从一个阶段切换到另一阶段的机制中，适应性策略就会变得更加有效。与许多其他生物一样，蟋蟀也对光周期高度敏感，并表现出广泛的反应（Alexander，1968；Fuzeau-Braesch，1966；Ismail 和 Fuzeau-Braesch，1976；Masaki，1966、1967、1972、1973；Masaki 和 Ohmachi，1967；Masaki 和 Oyama，1963；佐伯，1966；田中等人，1976）。滞育的起源和相关的光周期反应无疑是温带地区蟋蟀进化的最重要的关键之一。然而，显然不可能从任何化石材料中推断出这种进化。只有比较方法才能给出解决问题的可行途径。
sequence in relation to the seasonal changes, and the individual life cycles in each species are more or less synchronized. Among those species inhabiting the main part of the Japanese islands to the north of 30° N, only Gryllodes sigiUatus and Myrmecophilus sapporoensis can be found at various stages throughout the year. The fact that these exceptional species are confined to special habitats protected from violent fluc tuations of weather conditions, houses and ant nests, respectively, suggests that adaptation to temperate climates requires a definite pattern of seasonal life cycle. The latter is, of course, due to the existence in the life cycle of a particular stage highly resistant to a long period of arrested development. Adaptation to wide seasonal fluctuations in the environment is therefore not attained by a general increase in the tolerance range, but by the physiological division of the developmental cycle into the active and diapause phases with dif ferent optima of temperature, roughly corresponding to the summer and winter conditions, respectively (Browning, 1952a,b; Hogan, 1960a,b; Masaki, 1960, 1962, 1963, 1965; Rakshpal, 1962a,b,c, 1964). In view of the principle of allocation (Levins, 1968), this specialization seems to give a higher adaptability to temperate climates. It enables crickets to skip the harsh season by the diapause phase without imped ing adaptation by the active phase to the favorable season. The syn chronization of breeding activity might have been another impetus to this line of evolution, or simply a due consequence of the seasonal development. If an appropriate seasonal cue is incorporated into the mechanism switching the physiological state from one phase to the other, the adaptive tactic becomes more efficient. Like many other organisms, crickets also are highly sensitive to photoperiod, and show a wide spectrum of responses (Alexander, 1968; Fuzeau-Braesch, 1966; Ismail and Fuzeau-Braesch, 1976; Masaki, 1966, 1967, 1972, 1973; Masaki and Ohmachi, 1967; Masaki and Oyama, 1963; Saeki, 1966; Tanaka et al., 1976). The origins of diapause and associated photoperiodic responses are without doubt one of the most important pivots in the evolution of crickets in the temperate region. It seems, however, obviously im possible to infer this sort of evolution from any fossil materials. Only comparative methods will give a feasible way of approach to the problem.