Replication data for: Rapid life-history evolution in a wild Daphnia pulex population in response to novel size-dependent predation

This data set represent the results from a experiment designed to uncover potential rapid life-history evolution in a Daphnia pulex population in response to a shift in predation regime from phantom midge larvae (Chaoborus flavicans) to fish (Perca fluviatilis) after the illegal intoduction of perch to the study site, Lake Myravatn in the western part of Norway. The aim was to disentangle possible genetic change from phenotypic change in life-history traits. D. pulex were collected before and after the introduction of fish, to create seperate linages. 13 pre-introduction (before the perch-
introduction) and 14 post-introduction (after the perch-introduction) clones, in total 27 clones, were used in the experiment. For logistic reasons, the experiment was performed in three separate but procedurally identical batches. Juveniles born within 3-hour intervals were kept in 200 ml glass jars until 45 hours old, and then transferred individually into 70 ml glass jars. Animals were maintained in a climate room at 19 °C with a 16:8 light:dark regime throughout the experiment. All animals were photographed daily for lenght-at-age measurements and when approaching time of maturation, the animals were checked every three hours until all were mature. Juveniles were counted for the first three clutches. Egg size was measured from the photographs of females bearing their first clutch.

本数据集涵盖一项旨在探究蚤状溞（Daphnia pulex）种群快速生活史演化潜力的实验结果。该实验针对挪威西部米拉瓦特恩湖（Lake Myravatn）发生的非法引入河鲈（Perca fluviatilis）事件，研究该种群在捕食者群落从黄色幽蚊（Chaoborus flavicans）幼虫转变为河鲈后的生活史响应。

本研究的核心目标是区分生活史性状（life-history traits）中可能存在的遗传变化与表型变化（phenotypic change）。研究人员在河鲈引入前后分别采集蚤状溞个体以构建独立克隆（clone）谱系。本实验共使用27个克隆株系，其中河鲈引入前的株系13个，引入后的株系14个。

受实验后勤条件限制，实验分为三个独立但操作流程完全一致的批次开展。将3小时内孵化的幼体置于200毫升玻璃容器中饲养至45小时龄，随后将其单独转移至70毫升玻璃容器中。整个实验过程中，所有个体均饲养于温度19℃、光暗周期（light:dark regime）为16:8的气候室（climate room）内。每日对所有实验个体进行拍摄以开展体长-日龄测量；当个体接近成熟阶段时，每3小时检查一次直至所有个体均完成成熟。统计个体前三次产卵所产幼体的数量，并从携带首次产卵卵团的雌性个体照片中测量卵的尺寸。