Modelling the leaping capabilities of feathered theropods and the implications for a novel theory of the evolution of powered flight

一亿五千万年前，鸟类进化出了动力飞行。鸟类的飞行究竟是如何进化而来的，这是一个相当有争议的话题，但人们认为它是通过“翅膀辅助倾斜奔跑”或“从树上下来”发生的。然而，很少有鸟类会跑着起飞，更少的鸟类会爬上树或窗台，然后“摔”起来，而是跳起来。当活着的鸟类脱下腿时，它们的腿承担了大部分加速身体的初始工作，研究表明，腿提供了高达80%的升入空中所需的力量。此外，如果小型兽脚亚目恐龙通过跳跃来躲避捕食者，并且拥有细小的前肢羽毛，那么它们的跳跃范围可能比只有其中一种特征的情况下要大得多。因此，这个项目的基本假设是兽脚亚目恐龙通过起飞跳跃进化出飞行。为了探索这一假设，我们将系统地探索活体鸟类起飞的生物力学，并应用3D肌肉骨骼建模框架和从中获得的数据来模拟和理解兽脚亚目恐龙的起飞条件。

Over 150 million years ago birds evolved powered flight. How exactly birds' flight evolved is subject of considerable debate, but it is thought to have occurred via 'wing assisted incline running' or from 'the trees down'. However, very few living birds run to take off and even fewer climb a tree or ledge and then 'fall' into flight, instead they jump. When living birds take off their legs perform most of the initial work to accelerate their bodies and it has been shown that the legs provide up to 80% of the force required to get into the air. Moreover, if small theropods evaded predators with a jump and featured even tiny feathered fore limbs, their jump would likely have had a greatly extended range compared to the conditions in which only one of these features were available to them. The underlying hypothesis of this project is therefore that theropod dinosaurs evolved flight via a take-off jump.To explore this hypothesis we will systematically explore the biomechanics of the take-off in living birds and apply the 3D musculoskeletal modelling framework and data derived from these to model and understand the take-off conditions in theropod dinosaurs.