Male responses to sperm competition risk associated with increased macronutrient intake and reduced lifespan

Increased expenditure on the ejaculate is a taxonomically widespread male response to sperm competition. Increased ejaculate expenditure is assumed to come at a cost to future reproduction, otherwise males should always invest maximally. However, the life-history costs of strategic ejaculation are not well documented. Macronutrient intake is known to affect the trade-off between reproduction and lifespan. Intakes of protein and carbohydrate that maximise reproduction are often differ from those that maximise lifespan. Here, we asked whether strategic expenditure on the ejaculate by male crickets, Teleogryllus oceanicus, is mediated by macronutrient intake, and whether it comes at a cost of reduced lifespan. Males were exposed to rival song throughout their lifespan or were held in a silent non-competitive environment. Males exposed to song had a higher intake of both protein and carbohydrate, they reached adulthood sooner, produced ejaculates of higher quality, and died sooner than male..., , , This excel file contains three data sheets with data necessary to reproduce the analyses and figures provided within Simmons & Chan 2023. Sheet 1, intake summary & trait data Column - description A - Cricket - ID of individual cricket coded by treatment and a unique number (e.g. A1 or B1). A and B refers to two occasions on which 8th instar nymphs were drawn from the stock population.. B - Treatment - NS, silent or no-song environment; S, song environment C - Date eclosed to adult D - Death - date of death E - weight at adult eclosion in grams F - total amount of Carbohydrate consumed during lifetime (from sheet C intake) G- total amount of Protein consumed during lifetime (from sheet P intake) H - intake of C per gram of cricket per day of life I - intake of P per gram of cricket per day of life J - lifespan (days alive) K - days from 9th instar moult to adult moult L - spermatophore (sphor 1) on day 14, yes=1, no=0 M - number of live sperm stained green in first...针对精子竞争的雄性射精投入增加，是分类群中广泛存在的雄性应对策略。学界普遍认为，射精投入的增加会以未来繁殖适合度为代价，否则雄性本应始终最大化其投入。然而，策略性射精的生活史成本尚未得到充分记录。已知大量营养素（macronutrient）摄入会影响繁殖与寿命之间的权衡，而最大化繁殖所需的蛋白质与碳水化合物摄入量，往往与最大化寿命所需的摄入量存在差异。本研究以海洋蟋蟀（Teleogryllus oceanicus）为研究对象，探讨雄性的策略性射精投入是否受大量营养素摄入的调控，以及该投入是否会以寿命缩短为代价。实验中，雄性蟋蟀全程暴露于同类雄性的鸣唱声中，或置于无鸣唱的非竞争环境中。结果显示，暴露于鸣唱声的雄性蟋蟀，其蛋白质与碳水化合物摄入量均更高，成熟更快，射精质量更佳，且寿命更短。 本Excel文件包含三个数据表，涵盖了复现Simmons & Chan 2023年研究中的分析与图表所需的全部数据。 数据表1：摄入概况与性状数据 各列说明如下： A列：蟋蟀编号——以处理组与唯一编号编码的单只蟋蟀标识（例如A1或B1）。其中A与B代表从种群中选取8龄若虫的两个批次。 B列：处理组——NS：无鸣唱（沉默）环境；S：鸣唱环境 C列：成虫羽化日期 D列：死亡日期 E列：成虫羽化时的体重（单位：克） F列：终身摄入碳水化合物总量（数据来自摄入数据表C） G列：终身摄入蛋白质总量（数据来自摄入数据表P） H列：单位体重每日碳水化合物摄入量 I列：单位体重每日蛋白质摄入量 J列：寿命（存活天数） K列：从第9龄蜕皮至成虫蜕皮的天数 L列：第14天的精荚（spermatophore，简称sphor 1）情况：是=1，否=0 M列：首次样本中被染为绿色的活精子数量