Fig. 3
a: The rate of oxygen consumption (\( \dot{V} \)O2; mlO2kg− 1 min− 1) in relation to speed of pumas walking on a treadmill at an incline of 6.8° (n = 16, triangles, dashed line) and level walking at 0° (n = 20, circles, solid line). Point colour indicates individual pumas, two resting and locomoting on the treadmill (black, white), one resting only (grey) and one measurement where the ID was not noted (red). b: Calculated rate of oxygen consumption (\( \dot{V} \)O2; mlO2kg− 1 min− 1) in relation to speed for wild puma travelling on inclines. \( \dot{V} \)O2 was calculated from Eq. 9 using measured puma speeds and path angles. Path angle is represented by colour where yellow indicates pumas climbing up a steep path angle, and blue indicates pumas climbing a shallow path angle (see “Path Angle” scale). N = 2862 measurements of four wild pumas. Lines indicate \( \dot{V} \)O2 when walking on the level (A) and on the mean preferred path angle (B). The dashed and dotted lines indicate the predicted \( \dot{V} \)O2 if the mean topographical slope angle was to increase by 10° (C) or 20° (D) with increasing mean path angle accordingly. c: Modelled \( \dot{V} \)O2 (mlO2kg− 1 min− 1) for wild pumas from Eq. 9, using mean speeds of all recorded locomotion events at each path angle. Point size represents the frequency of use of each path angle by wild pumas. Values for \( \dot{V} \)O2 on inclines greater than 20 degrees should be interpreted with caution