ABOVE: An Etruscan shrew (Suncus etruscus)
AXEL GEBAUER
The smallest terrestrial mammal, the Etruscan shrew (Suncus etruscus), is about as big as a person’s thumb and no heavier than a couple of paper clips. To have enough energy to survive, it must eat eight or more times its body weight daily and therefore doesn’t hibernate. Instead, according to a study published November 30 in PNAS, in winter, these shrews lose 28 percent of the volume from their somatosensory cortex, which likely helps them conserve energy.
“This phenomenon of an animal that is not a hibernator still implementing these energy saving strategies is just stunning,” says Christine Schwartz, a neuroscientist who studies hibernation at the University of Wisconsin La Crosse and was not involved in the work.
Scientists have shown before that red-toothed shrews, which belong to a group separate from the Etruscan shrew, are born and grow to their full body ...
