Spatio-temporal gait characteristics of level and vertical locomotion in aground-dwelling and a climbing gecko

The effects of incline (vertical versus horizontal) on spatio-temporal gait characteristics (stride and step length, frequency, duty factor, degree of sprawling) were measured over a range of speeds in a ground-dwelling (Eubl epharis macularius) and a climbing (Gekko gecko) species of gecko, Surprisi ngly, the climbing species also performs very well when moving on the horiz ontal substratum. In the present experiments, climbing speeds ranged from 0 .6 to 1.2 m s(-1), whereas speeds for level locomotion were between 0.6 and 1.8 m s(-1). In contrast, the vertical climbing capacities of the ground-d weller are limited (speeds below 0.1 m s(-1) versus level speeds between 0. 2 and 1.1 ms(-1)). In general, me demonstrate that very little adjustment i n gait characteristics is made by either species when they are forced to mo ve on their non-habitual substratum. Moreover, gait characteristics differ little between the species despite the clear differences in ecological nich e, Higher level or climbing speeds are realized mainly (or exclusively in t he case of level locomotion in G. gecko) by increasing stride frequency. St ride lengths and duty factors vary with speed in the ground-dweller, but no t in the climbing species. Step length and the degree of sprawling are spee d-independent (except for hind-limb sprawling in G. gecko on the level). It is argued that this common strategy suits climbing (fixed spatial variable s, no floating phases) rather than level locomotion.