Abstract
Temperate zone lunged, temperate zone lungless, and neotropical lungless salamanders were examined to determine if differences in rates of oxygen consumption (VΜ) after vigorous activity are correlated with body temperature and size differences among the three groups. Salamanders were stimulated electrically for two minutes, and VΜ measured for 75 minutes afterwards using Warburg manometers. Slopes of regressions of log maximum VΜ against log body size are greater for lunged salamanders than for lungless salamanders at 5Β°, 15Β° and 25Β°C; differences in slope among groups do not change with temperature. Slopes of log aerobic scopeβlog body size regressions are also greater for lunged salamanders than for lungless salamanders, but this difference increases with temperature. Lungless salamanders repay oxygen debt more slowly than lunged salamanders at large body size and high temperatures. Q~10~'s of maximum VΜ and aerobic scope increase less with temperature in lungless salamander species than in lunged salamander species.
If differences in VΜ are due to respiratory surface area differences, then lunglessness may restrict postβactivity VΜ at large body size and high temperatures. However, neotropical lungless salamanders live at high temperatures and large sizes, which suggests that high postβactivity VΜ is unnecessary for many salamanders.