by Heidi Ar­jes — Have you ever won­dered how in­di­vid­ual fin­gers form? If you have taken a de­vel­op­men­tal bi­ol­ogy class, you know that the hand first de­vel­ops as a mit­ten-like struc­ture with the fu­ture fin­gers con­nected (Fig­ure 1). Later, dur­ing nor­mal de­vel­op­ment, the cells in the ar­eas be­tween the fin­gers un­dergo pro­grammed cell death, and thus…