Risk-taking Urban bats vs. hesitant rural bats: urbanization drives behavioral flexibility and brain plasticity in Egyptian fruit bats

Urbanization is arguably the most dramatic phenomenon influencing animals around the world. Although many behavioral adjustments have been described in urban animal populations, we know very little about the possible impacts of urbanization on animals' brains. Egyptian fruit bats thrive in both urban and rural environments, but they are faced with very different challenges in these two environments. We show that urban fruit bats are significantly bolder than rural bats, a characteristic that is probably crucial for their survival in urban environments. Magnetic Resonance Imaging revealed that the brains of the two populations differ in areas related to navigation, sensing and reward. Over a month in the lab, both rural and urban bats became bolder and a correlation between brain and behavior suggests that neural plasticity in the brain's fear-related network and specifically in the amygdala is related to this behavioral flexibility. Linking brain plasticity with behavioral flexibility in wild free-behaving animals is very difficult. This study shows the potential of combining non-invasive imaging and behavioral assay in order to reveal the impact of global ecological changes on wild animals. The data presented here is the preprocessed MRI scans of 84 urban (city) and rural (country) bats. It was preprocessed and asigned into 3 contrasts: gray matter (GM) derived from anatomical scans, and functional anisotropy (FA) and mean diffusivity (MD) derived from DTI scans. The numbers at the scans names denote specific individual bats, with the same numbers in the before and after scans. In the sorted data folder, you can find all the scans divided into the 3 different contrast. inside each contrast folder there are 16 folders- 8 for urban bats start with U and 8 folders for rural bats start with R, the numbers 1-5 are batch numbers- different repetitions of the experiment and for batches 1-3 there are 2 scans available (before and after), folders with the "after" scans end with b. The folder scripts contains Matlab scripts and mat files that were used in the data analysis. The main script is "full_analysis" that uses other scripts from the folder for the statistical analysis. In the sorted data folder there is Masks folder in which you can find 2 masks that are needed for the scripts and a mean bat file to visualize the results on.城市化堪称影响全球野生动物的最显著变革性现象之一。尽管学界已对城市动物种群的诸多行为调整展开相关报道，但我们对城市化可能对动物大脑造成的影响仍知之甚少。埃及果蝠既能在城市环境中生存繁衍，也能适应乡村生境，但二者面临的生存挑战截然不同。本研究证实，城市生境中的埃及果蝠相较于乡村种群展现出显著更高的大胆性，这一特征或许是其在城市环境中存活的关键要素。磁共振成像（Magnetic Resonance Imaging, MRI）结果显示，两个种群的果蝠大脑在与导航、感知及奖赏处理相关的脑区存在差异。在实验室为期一个月的饲养周期中，乡村与城市种群的果蝠均表现出胆量提升的趋势；脑结构与行为的相关性分析表明，大脑恐惧相关神经网络（尤其是杏仁核（amygdala））的神经可塑性，与这种行为灵活性存在关联。在野生自由活动的动物中建立脑可塑性与行为灵活性之间的关联极具挑战。本研究证实，结合非侵入式成像技术与行为学实验检测的方法，有望揭示全球生态变化对野生动物的影响。本次公开的预处理磁共振成像扫描数据共涵盖84只埃及果蝠的扫描结果，其中包含城市种群与乡村种群个体。该数据已完成预处理，并被划分为3种对比度类型：源自解剖扫描的灰质（gray matter, GM）、以及源自弥散张量成像（diffusion tensor imaging, DTI）扫描的各向异性分数（functional anisotropy, FA）与平均弥散率（mean diffusivity, MD）。扫描文件的命名数字对应具体的果蝠个体，同一数字的扫描文件对应同一受试个体的实验前后两次扫描结果。在整理完成的数据文件夹中，所有扫描文件已按3种对比度类型分类存储。每个对比度类型的子文件夹内包含16个次级文件夹：8个以字母U开头的城市种群果蝠文件夹，以及8个以字母R开头的乡村种群果蝠文件夹。其中数字1-5代表实验批次编号，对应不同的实验重复组；批次1至3的组别有两次扫描结果（实验前与实验后），以字母b结尾的文件夹对应实验后扫描的数据。scripts文件夹中存放了本次数据分析所用的Matlab脚本文件与mat数据文件，核心脚本为"full_analysis"，该脚本会调用文件夹内的其他脚本完成统计分析工作。整理完成的数据文件夹中还包含Masks文件夹，其中存放了脚本运行所需的2个脑区掩模文件，以及用于可视化分析结果的标准化果蝠脑模板文件。