The dynamics and energetics of hunting in the cheetah

猎豹可以以每小时65英里的速度冲刺，这使它成为目前为止最快的陆地动物--精英赛狗和赛马(以及动物园里追逐诱饵的猎豹)只能跑到每小时40英里。猎豹的机动性也很强，即使是最敏捷的猎物也能捕捉到。但猎豹是什么让它能做到这一点呢？目前我们根本不知道。被广泛引用的“猎豹最高速度”来自1965年一只猎豹测量的三次奔跑。为了找出答案，我们需要测量猎豹在野外狩猎时的表现--这是唯一达到峰值速度和机动的时候。然而，尽管猎豹被认为几乎每天都在捕猎，但狩猎很难直接观察到。我们计划为野生猎豹配备项圈，这些项圈配备了我们专门为这类工作开发的独特技术。每个项圈包含一个特殊的高精度GPS来精确定位位置和速度，以及加速度传感器、微型陀螺仪、指南针和一台微型低功耗计算机。传感器可以检测到猎豹的准确脚步模式--每只脚走了多少步，以及每只脚何时落地。项圈监测猎豹在哪里以及它在做什么-休息、行走，最重要的是狩猎，只有在猎豹快速移动时才收集详细信息(每秒记录数据高达300次)。根据这些数据，我们可以重建猎豹在狩猎过程中的准确运动。在其他时间，定期的位置更新和行为被记录下来，集成的太阳能电池板为电池充电。项圈数据被存储起来，供以后通过集成无线电链路下载。我们的目标是使用安装在支架上的高分辨率高速摄像机从地面和空中拍摄猎豹，该摄像机可以自动指向GPS获取的位置。项圈通过无线电链接告诉坐骑将摄像机对准哪里，摄像机跟踪猎豹的移动(实际上，我们将摄像机对准猎豹的前方，也是为了看到猎物)。由于摄像机和项圈在时间上是精确同步的，我们可以一步一步地检查狩猎的项圈数据和视频片段，包括地形、障碍物和与猎物的互动。我们将使用统计分析技术和计算机建模相结合的方法来检查极限和对表现的帮助，如握力、肌肉力量需求、转身启动和尾部移动。解释猎豹速度和敏捷性的关键可能在于它的肌肉。因此，我们将研究猎豹肌肉纤维收缩的速度和强度(通过研究使用细微活组织检查针采集的微小样本)，以找出它的特性是否与其他猫或其他精英动物(如人类、赛马或灰狗)的特性不同。该项目将首次记录一天24小时野生猎豹的详细数据。这些数据不仅使我们能够了解猎豹如何实现其速度和机动性，还将使我们能够以前所未有的细节探索猎豹的行为、栖息地的使用和领地的大小，这对于制定猎豹长期生存的管理策略是必要的。肌肉研究可能为致力于开发治疗人类和动物肌肉问题的新方法的科学家提供新的信息。我们的结果和数据收集技术将为科学家提供新的工具，不仅研究生物力学、行为和生态学，而且还希望了解疾病在野生种群中的传播。我们预计工程师也会对我们的工作感兴趣，因为了解猎豹的设计可能有助于重量更轻、腿部更快的机器人的设计，也有助于军队，因为这些技术和分析方法可以用于在战场上跟踪士兵。最后，我们希望我们的工作能够吸引公众，展示数学、工程学和生物学如何帮助我们解开自然的秘密，并激励未来的科学家。

A cheetah can sprint at 65 mph, making it the fastest land animal by far - elite racing greyhounds and racehorses (and zoo cheetahs chasing a lure) only manage 40 mph. Cheetahs are also highly manoeuvrable, allowing them to catch even the most agile of prey. But what is it about the cheetah that enables it to do this? At the moment we simply don't know. The highly cited 'cheetah top speed' comes from just three measured runs by one individual cheetah in 1965. To find out, we need to measure the performance of cheetah during hunting in the wild - the only time that peak speed and manoeuvring are achieved. However, whilst cheetahs are believed to hunt almost daily, hunting is hard to observe directly.We plan to fit wild cheetah with collars equipped with unique technology that we have developed especially for this type of work. Each collar contains a special high accuracy GPS to pinpoint location and speed along with acceleration sensors, miniature gyroscopes, a compass and a tiny low power computer. The sensors can detect the cheetah's exact footfall pattern - how many strides and when each foot is on the ground. The collars monitor where the cheetah is and what it is doing - resting, walking, and most importantly, hunting and only collects detailed information when the cheetah is moving quickly (logging data up to 300 times per second). From the data, we can reconstruct the exact movement of the cheetah during a hunt. At other times, regular position updates and behaviour are recorded and the integrated solar panels recharge the batteries. The collar data is stored for later download via an integral radio-link.We aim to film cheetah hunts from the ground and air using a high resolution high speed video camera on a mount that automatically points at a GPS derived location. The collars tell the mount where to point the camera via a radio link and the camera tracks the cheetah's movement (we actually aim the camera just ahead of the cheetah to see the prey as well). Because the cameras and collars are exactly synchronised in time, we can examine the collar data and video footage of the hunt step by step, including the terrain, obstacles and interaction with the prey. We will use a combination of statistical analysis techniques and computer modelling to examine limits and aids to performance like grip, muscle power requirements, turn initiation and tail movement.The key to explaining the cheetah's speed and agility may lie in its muscles. Therefore we will study how quickly and powerfully cheetah muscle fibres can contract (by studying miniscule samples taken using a fine biopsy needle) to find out whether its properties differ from those of other cats or other elite performance animals such as humans, racehorses or greyhounds.This project will be the first to record such detailed data on wild cheetahs 24 hours a day. As well as enabling us to find out how cheetahs achieve their speed and manoeuvrability, these data will also enable us to explore - in unprecedented detail - cheetah behaviour, home range use and territory size, which is necessary to develop management strategies for the cheetah's long-term survival. The muscle studies may contribute new information for scientists working to develop new treatments for muscle problems in humans and animals. Our results and data collection techniques will provide new tools for scientists working not only on biomechanics, behaviour and ecology, but also those wanting to understand the spread of disease in wild populations. We expect our work also to be of interest to engineers, as understanding the cheetah's design may contribute to the design of lighter weight, faster legged robots and the military too, as the technology and analytical methods could be used for tracking soldiers on the battlefield. Finally, we hope our work will engage the public, showcasing how maths, engineering, and biology can help us unravel nature's secrets and inspire scientists of the future.