Bartels H, Bartels R, Baumann R, Fons R, Jürgens K D, Wright P
C R Acad Hebd Seances Acad Sci D. 1978 Apr 24;286(16):1195-8.
A high oxygen capacity combined with a low oxygen affinity and a large Bohr effect achieve a high oxygen transport capacity in small shrews. The high metabolic rate (Suncus estruscus: 100 to 350 ml O2/kg. min) can be explained by the combination of the favorable blood parameters with a high relative heart weight (1,2% of body weight) and heart frequencies of 1,000 to 1,350 per minute.