Different biological architectures of flexible systems that allow grasping evolved multiple times independently in various groups of animals, from prehensile tails in seahorses to flexible arms in brittle stars. Studying the underlying morphology and biomechanics of how anatomical traits define functional performance in a broad evolutionary context allows for identifying key characteristics that can turn a complex system into a prehensile tool. The grasping tail in seahorses and arms in brittle stars are of special interest, as they are on the bridge between soft and hard robotics, combining the advantages of both and thus providing innovative inspiration for a new generation of robotic systems. To allow the development of design and control concepts for such robotic applications, there is a need for a proper understanding of how these biological systems are built, how they function, how the anatomy controls specific functional traits, and how evolution has modified an ancestral configuration into a fully functional grasping configuration. This project, in collaboration with engineers who focus on the robotics part, will deal with the underlying biology of these two prehensile systems.