It is the way the words are put together that gives the Constitution its meaning. The cells come together in the right way to form fingers and other body parts. Or, in the case of leopards and zebras, pigment cells accumulate in the right pattern to form spots and stripes. Which gets him back to slime mold. But when food is scarce, starving slime-mold cells send chemical signals to each other.
Some cells form a long stalk and others form a spore-filled sac atop the stalk.
The spores are ejected from the sac to form new slime-mold amoebas, and the process begins anew. The way slime-mold cells sense each other, move around, join together and differentiate is quite similar to the way cells behave in developing leopards, zebras, humans or other creatures. He discussed his work recently during the university's quarterly Science at Breakfast lecture. The cells detect chemical signals from each other. Those external chemical signals are converted into internal signals that tell each cell what to do.