Data from: Nutrient regulation strategies differ between cricket morphs that trade-off dispersal and reproduction

1. Nutrient regulation should covary with life history, but actual demonstrations of this connection are rare. 2. Here we use a wing-polymorphic cricket, Gryllus firmus, that trades-off dispersal and reproduction; the long-winged morph with functional flight muscles (LW(f)) is adapted for dispersal at the expense of egg production, while the short-winged (SW) morph is adapted for egg production at the expense of flight. We explore the extent to which these two morphs differentially regulate macronutrient intake to best match their life history strategy. 3. In a “choice” experiment, we offered female crickets of each morph (LW(f) and SW) two nutritionally complementary foods varying in protein and digestible carbohydrate content. In a second “no-choice” experiment, we confined crickets to one of five foods, each with a different protein-carbohydrate-ratio. In both experiments, and for both morphs, we measured food intake, mass gain, and lipid concentration. 4. In the “choice” experiments, LW(f) females selected a more carbohydrate-biased diet than SW females. The two morphs gained similar total mass, but the LW morph had higher lipid concentration. 5. In the no-choice experiment, the two morphs practiced different nutrient “consumption rules.” SW females ate similar total nutrient amounts (protein plus carbohydrate) across diets, while LW(f) females decreased intake as the protein-carbohydrate ratio of the available food became increasingly imbalanced. Overall mass gain was marginally higher in the SW morph, and lowest on the diets that were extremely carbohydrate-biased. LW(f) and SW females had similar lipid concentrations across the diets, even though LW(f) crickets ate less carbohydrate on the two carbohydrate-biased diets. Our data suggest that for LW(f) females there are costs of overeating nutrients in excess of requirements, but they are efficient at utilizing ingested nutrients. 6. Our results shed new light on how the nutritional environment interacts with the direct trade-off between dispersal and reproduction occurring in adult G. firmus crickets. Dispersal is linked to heightened diet selectivity and an emphasis on nutrients promoting flight fuel (lipid) storage over protein acquisition for egg-laying, such that nutritional regulation complements the metabolic mechanisms that generate this trade-off.

1. 营养调控应与生活史协同变化，但此类关联的实际实证案例却较为罕见。
2. 本研究选用具翅多态性的南方田野蟋蟀（Gryllus firmus），其扩散与繁殖存在权衡关系：长翅型个体拥有功能性飞行肌（LW(f)），以牺牲产卵能力为代价适应扩散；短翅型（SW）则以牺牲飞行能力为代价适应繁殖。我们旨在探究这两种翅型在宏量营养素（macronutrient）摄入调控上的差异程度，以使其最契合各自的生活史策略。
3. 在"选择饲喂"实验中，我们为两种翅型（LW(f)与SW）的雌性蟋蟀提供两种营养互补的食物，二者的蛋白质与可消化碳水化合物含量存在差异。在第二项"无选择饲喂"实验中，我们将蟋蟀限制在五种食物中的一种，每种食物的蛋白质-碳水化合物比例（protein-carbohydrate-ratio）各不相同。两项实验中，我们均针对两种翅型的蟋蟀测定了食物摄入量、体重增量与脂质（lipid）浓度。
4. 在"选择饲喂"实验中，LW(f)雌性蟋蟀相较于SW雌性蟋蟀，选择了更偏向碳水化合物的日粮。两种翅型的总体重增量相近，但LW型个体的脂质浓度更高。
5. 在"无选择饲喂"实验中，两种翅型展现出不同的营养"摄入规则"。SW雌性蟋蟀在不同日粮下的总营养素摄入量（蛋白质+碳水化合物）相近，而LW(f)雌性蟋蟀的摄入量会随着可用食物的蛋白质-碳水化合物比例愈发失衡而降低。SW型的总体重增量略高，而在极度偏向碳水化合物的日粮组中体重增量最低。尽管LW(f)蟋蟀在两种高碳水日粮中的碳水化合物摄入量更低，但两种翅型雌性的脂质浓度在各日粮组中均无显著差异。我们的数据表明，对于LW(f)雌性而言，过量摄入超出需求的营养素会带来代价，但它们对摄入营养素的利用效率较高。
6. 我们的研究结果为解析营养环境与成年南方田野蟋蟀（G. firmus）所存在的扩散-繁殖直接权衡之间的相互作用提供了新视角。扩散行为与更高的日粮选择性相关，且相较于为产卵获取蛋白质，更侧重促进飞行燃料（脂质lipid）储存的营养素摄入，由此可见营养调控可与产生该权衡关系的代谢机制形成互补。