Don't break a leg: running birds from quail to ostrich prioritise leg safety and economy on uneven terrain.

ABSTRACT: Cursorial ground birds are paragons of bipedal running that span a 500-fold mass range from quail to ostrich. Here we investigate the task-level control priorities of cursorial birds by analysing how they negotiate single-step obstacles that create a conflict between body stability (attenuating deviations in body motion) and consistent leg force-length dynamics (for economy and leg safety). We also test the hypothesis that control priorities shift between body stability and leg safety with increasing body size, reflecting use of active control to overcome size-related challenges. Weight-support demands lead to a shift towards straighter legs and stiffer steady gait with increasing body size, but it remains unknown whether non-steady locomotor priorities diverge with size. We found that all

SUBMITTER: Birn-Jeffery AV 

PROVIDER: S-EPMC4213177 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature