Thermal adaptation and clinal mitochondrial DNA variation of European anchovy

http://rspb.royalsocietypublishing.org/content/281/1792/20141093.short

It seems that anchovies broadly possess one of two mtDNA types, and which type a fish possesses is related to the latitudes at which it lives. This paper shows that ocean temperature is the strongest of the investigated possible determinants of anchovy mtDNA haplotype. The authors discuss the specific molecular effects of the differences between haplotypes, including some residue changes in Complex III. They speculate on the OXPHOS implications of these changes, but don't consider proton leak, which I think may be affected by the residue changes (they're on the side of the complex, though I can't see immediately if these sites are where the complex contacts the membrane). Generally -- a fun example of possible environment adaptation in mtDNA haplotypes.