Age, Sex, and Weight Comparisons in Three Species of Shrews

Abstract

The extreme variability in species of shrews has confused systematists for some time. Shrews were conceded to be more variable than most other mammalian groups and taxonomically extremely difficult to handle. Only relatively recently have the sources of this variability been recognized and analyzed. Several recent authors have studied growth and sexual patterns in Sorex and related genera. These studies establish that the so-called “inherent variability” of shrews is actually no greater than that of many mammalian groups once growth and secondary sexual variation are understood. When ample specimens for comparison are available, these sources of variation cause little difficulty. The small size and the difficulty of obtaining specimens in many areas remain as the chief deterrents to full understanding of the systematics of Sorex.