While the disparity in metabolism vs size, is greater
in automatic endotherms, I disagree that the small
animals = higher metabolisms statement doesn't hold
true for the rest of the animal world. The metabolism
of a little whiptail lizard, or anole, is noticeably
faster than that of a large iguana, or Komodo dragon.
That smaller reptiles have larger metabolic
fluctuations with temperature should be beside the
point, as the small critters usually work hard at
keeping their body temperatures high enough for their
metabolism to be at optimum efficiency.