Flies, mice and humans share a common walking pattern across species

Scientists have uncovered a universal rule governing the speed of limb movement across vastly different species. In a comparative study involving flies, mice and humans, researchers from the University of Cologne and Forschungszentrum Jülich found that joints positioned farther from the body’s center move faster than those closer to the core. The pattern held true whether the organism was a tiny insect or a large mammal, suggesting a fundamental biomechanical principle that transcends size and anatomy.

Led by Professor Dr. Silvia Daun and Professor Dr. Graziana Gatto, the team recorded high‑resolution motion data from each species and analyzed joint velocities relative to body length. The results showed a consistent gradient: distal joints—such as the wings of a fly or the toes of a mouse—exhibited higher angular speeds than proximal joints like the thorax or pelvis. The researchers argue that this relationship reflects the mechanical advantage of longer lever arms, allowing faster movement with less muscular effort.

The findings have implications for fields ranging from robotics to evolutionary biology. By revealing a shared kinematic strategy, the study provides a benchmark for designing biomimetic machines and offers insight into how natural selection shapes locomotor efficiency across the animal kingdom.