Abstract

Animals are increasingly exposed to both artificial light at night (ALAN; a.k.a., ecological light pollution) and heat waves. Traditionally, the effects of ALAN and heat waves have been investigated in isolation, and results indicate mixed support for their costs to important decisions made at specific stages of reproduction (i.e., before, during, and after mating). Therefore, we used a factorial design to manipulate temperature and light conditions during adulthood in female variable field crickets (Gryllus lineaticeps) to determine (1) whether ALAN has stage-specific effects on reproductive decisions and (2) if ALAN effects on reproduction interact with a simulated heat wave. We found that ALAN simulating bright urban lighting promoted mating success, and a simulated heat wave resulted in even greater benefits to reproduction, including increased reproductive investment (ovary mass prior to mating), the efficiency by which food was converted into reproductive tissue, and reproductive output (number of eggs laid). Heat wave and ALAN did not modulate the effect of one another because we found no evidence of interactive (e.g., synergistic or antagonistic) effects of temperature and light treatments on any reproductive trait. Our study is the first to examine the combined effects of ALAN and heat waves across reproductive stages, and we found that these two increasingly common environmental factors may generally benefit reproduction in an insect.

Significance statement

Animals are increasingly exposed to artificial light at night (a.k.a., ecological light pollution) and heat waves, but the combined effects of these two potential stressors are unknown. Therefore, we manipulated temperature and light conditions during adulthood in female variable field crickets (Gryllus lineaticeps) to examine effects across three important reproductive stages—before, during, and after mating. We found that ALAN simulating bright urban lighting promoted mating success, and a simulated heat wave resulted in even greater benefits to reproduction, including increased reproductive investment (ovary mass prior to mating) and reproductive output (number of eggs laid after mating). Our results indicate that these two increasingly common environmental factors may generally benefit reproduction in an insect.

中文翻译：

---

夜间高强度人造光和模拟热浪下的蟋蟀繁殖

摘要

动物在夜间越来越多地暴露在人造光（ALAN；又名生态光污染）和热浪中。传统上，ALAN 和热浪的影响是孤立地研究的，结果表明，在特定繁殖阶段（即交配前、交配期间和交配后）做出的重要决策的成本支持混合支持。因此，我们使用因子设计来控制雌性可变田间蟋蟀（Gryllus lineaticeps）成年期的温度和光照条件。) 以确定 (1) ALAN 是否对生殖决策具有特定阶段的影响，以及 (2) ALAN 对生殖的影响是否与模拟的热浪相互作用。我们发现 ALAN 模拟明亮的城市照明促进了交配成功，而模拟的热浪对生殖产生了更大的好处，包括增加生殖投资（交配前的卵巢质量）、食物转化为生殖组织的效率以及生殖产量（产卵数）。热浪和 ALAN 没有调节彼此的影响，因为我们没有发现温度和光处理对任何生殖性状的相互作用（例如协同或拮抗）影响的证据。我们的研究首次检验了 ALAN 和热浪在生殖阶段的综合影响，

意义陈述

动物在夜间越来越多地暴露在人造光（又名生态光污染）和热浪中，但这两种潜在压力源的综合影响尚不清楚。因此，我们在成年期对雌性可变蟋蟀（Gryllus lineaticeps) 检查三个重要生殖阶段的影响——交配前、交配期间和交配后。我们发现 ALAN 模拟明亮的城市照明促进了交配成功，模拟热浪对繁殖产生了更大的好处，包括增加繁殖投资（交配前的卵巢质量）和繁殖产量（交配后产卵的数量）。我们的研究结果表明，这两种日益常见的环境因素通常可能有利于昆虫的繁殖。