  Nobel laureates cluster together. 696 of the 727 winners of the Nobel Prize
in physics, chemistry, medicine, and economics belong to one single academic
family tree. 668 trace their ancestry to Emmanuel Stupanus, 228 to Lord
Rayleigh (physics, 1904). Craig Mello (medicine, 2006) counts 51 Nobelists
among his ancestors. Chemistry laureates have the most Nobel ancestors and
descendants, economics laureates the fewest. Chemistry is the central
discipline. Its Nobelists have trained and are trained by Nobelists in other
fields. Nobelists in physics (medicine) have trained (by) others. Economics
stands apart. Openness to other disciplines is the same in recent and earlier
times. The familial concentration of Nobelists is lower now than it used to be.
