Genetical studies on the skeleton of the mouse. XXIV. Further data on skeletal variation in wild populations.

A Pilot experiment by Weber (1950) established the fact that the minor skeletal variations universally present in strains of tame mice are also encountered in wild populations; and that the incidence of individual variants may differ widely from population to population. In the decade since Weber's work many new variants have come to light, and it seemed desirable to repeat his observations on the more extensive range of variants now available. An opportunity to do so presented itself in 1956 when wild mice from various localities in the eastern U.S.A. became available for study. These animals had been collected for a totally different purpose. As is well known through the work of Dunn and his collaborators, there exists in the mouse a semi-dominant gene ( T ) for Brachyury or short-tail which in T /+ heterozygotes shortens the tail to a varying extent.