In many animals, there is a prolonged pre-reproductive period prior to sexual maturity. To avoid premature mating attempts, it is common for phenotypic changes to occur during this period that signal the onset of reproductive viability. Among the insects, pre-reproductive phases can last for up to 50% of the adult lifespan, but little is known about the accompanying phenotypic changes that signal sexual maturity. Contact pheromones such as cuticular hydrocarbons (CHCs) may fulfil this role, as they are known to change rapidly with age in many insects. Despite this, few studies have investigated CHC development in the context of sexual maturity or considered differences in CHC development between sexes. The blowflies (Diptera: Calliphoridae) provide an ideal system for such studies because CHCs are known to change rapidly with age and likely play an important role in sexual behaviour. As such, using the small hairy maggot blowfly Chrysomya varipes, we investigate whether there are age- and sex-specific changes in CHCs over the course of adult blowfly maturation. We show that: (1) major qualitative transitions in CHC expression coincide with the onset of sexual maturity and (2) these changes occur more slowly in females – in line with their extended pre-reproductive phase. We suggest that CHCs may play an important role in signalling sexual maturity in the small hairy maggot blowfly and that this species will likely serve as a useful model for understanding the complex ontogeny of cuticular hydrocarbons in insects.

中文翻译：

---

表皮碳氢化合物表达的主要转变与在蝇中的性成熟（双翅目：Calliphoridae）相吻合。

在许多动物中，性成熟前的生殖期延长。为了避免过早的交配尝试，通常在此期间发生表型变化，这标志着生殖能力的开始。在昆虫中，生殖前阶段可以持续长达成年寿命的50％，但对伴随性表型变化的信号知之甚少。接触信息素（例如表皮碳氢化合物（CHC））可能会发挥这种作用，因为众所周知，它们在许多昆虫中会随着年龄而迅速变化。尽管如此，很少有研究在性成熟的背景下研究CHC的发展，也没有考虑性别之间CHC的发展差异。苍蝇（双翅目：Calliphoridae）为此类研究提供了理想的系统，因为众所周知，CHC随着年龄的增长而迅速变化，并且可能在性行为中起重要作用。因此，使用小毛y蝇金枪鱼变异体，我们调查在成年的蝇fly成熟过程中，CHCs是否存在年龄和性别特异性变化。我们显示：（1）CHC表达的主要质变与性成熟的发生相吻合，（2）这些变化在女性中发生得更慢–与她们延长的生殖前期一致。我们建议CHC可能在发信号的小毛sexual蝇性成熟中起重要作用，并且该物种可能将成为了解昆虫表皮碳氢化合物复杂个体的有用模型。