Fig. 3

a Least squares mean maximal exertion time (MET) as a function of species and structure type. G. oceanica had a significantly longer MET than H. frenatus (P = 0.042), but there were no significant differences between structure types (P = 0.38) or the structure type-species interaction (P = 0.52). b Mean number of completed runs as a function of structure type and species. G. oceanica completed significantly more runs than H. frenatus (P < 0.0001), although there were no significant differences between structure types (P = 0.17) or the substrate type-species interaction (P = 0.97). * P < 0.05, ** P < 0.0001