Miller Soleille, Derenne Adam, Ellis-Felege Susan, Rhen Turk
Department of Biology, University of North Dakota, Box 9019, 10 Cornell Street, Grand Forks, ND 58202, USA.
Department of Psychology, University of North Dakota, Box 8380, 501 N Columbia Road, Grand Forks, ND 58202, USA.
Physiol Behav. 2020 Jun 1;220:112875. doi: 10.1016/j.physbeh.2020.112875. Epub 2020 Mar 16.
Temperature during embryogenesis determines sex and has been shown to influence other physiological traits in reptiles. The common snapping turtle (Chelydra serpentina) is an ideal model for testing how temperature impacts behavior in species that display temperature-dependent sex determination. Behavioral assays are crucial to understanding how a changing climate may affect whole organism function in the snapping turtle. Currently, there are few behavioral assays for semi-aquatic vertebrates like turtles. In this study, we used digital cameras to record behavior of fed and fasted hatchling turtles from different incubation temperatures in an open field setting for 20 min in 2018 and repeated the experiment in 2019. Open fields were circular tanks filled with water to a depth of 3.5 cm. Each field was split into four quadrants and two zones (inner and outer). The amount of time turtles spent actively moving, total distance travelled, and several other measures were collected and summarized automatically from videos with open source image analysis software (ImageJ). Satiety and incubation temperature had significant effects on total distance moved, time spent moving, and time moving in the outer zone. These findings indicate that temperature during embryogenesis has a long-lasting effect on neural mechanisms underlying exploratory or general locomotor behavior in turtles.
胚胎发育期间的温度决定性别，并且已被证明会影响爬行动物的其他生理特征。普通鳄龟（蛇鳄龟）是一个理想的模型，用于测试温度如何影响具有温度依赖型性别决定的物种的行为。行为测定对于理解气候变化如何影响鳄龟的整体生物体功能至关重要。目前，针对像龟这样的半水生脊椎动物的行为测定很少。在本研究中，我们使用数码相机在2018年的开放场地环境中记录了来自不同孵化温度的喂食和禁食幼龟的行为20分钟，并于2019年重复了该实验。开放场地是装满水至3.5厘米深的圆形水箱。每个场地被分成四个象限和两个区域（内区和外区）。使用开源图像分析软件（ImageJ）从视频中自动收集并汇总了龟积极移动的时间、行进的总距离以及其他几项测量数据。饱腹感和孵化温度对移动的总距离、移动时间以及在外区的移动时间有显著影响。这些发现表明，胚胎发育期间的温度对龟探索性或一般运动行为的神经机制具有长期影响。
