The Ancestry of the Nautilus - Time Machines - page 177

Miller of the University of Iowa, then the feigning expett on nautiloid
cephalopods. Millet, a workaholic of amazing endurance and longevity, had
the interesting habit of airbrushing the photos of his nautiloid specimens to
make them look bettet in his published monographs. In spite of such idio-
syncrasies (today considered anathema in all scholatly publications), he was
unchallenged in his specialty. He was a champion of distinguishing taxa on
the basis of only one or two morphological characters. For instance, in his
most impottant work, published in 1947, he wrote,
In general, diffetences in suture pattern [a stmcture formed by the
intetsection of the shell wall and the septum that is visible only
when the shell wall is removed] and ornamentation must be given
far mote weight than shape of the conch in the determination of
the taxonomic position of a genus or species of nautiloid
cephalopods. . . .
Miller's subsequent description of the genus Nautilus was indeed based largely
on the morphology of the suture pattern. He also recognized only living species
as members of genus Nautilus. These two concepts—that nautiloid genera (in-
cluding Nautilus) were best differentiated by sutures and ornament, and that
the genus Nautilus had no fossil record—were subsequently adopted by
Millet's heir to the title of world authority on the nautiloids, Bernard Kummel
of Harvard University, who, like Miller, believed that Nautilus first evolved in
the Late Tertiary (perhaps 5 million years ago) and was without any fossil
record. In 1956 in a latge monograph dealing with every known nautiloid
species from the Jurassic Period to the modern day, Kummel noted, "No fossil
species are assigned to the genus Nautilus. No Pliocene or Pleistocene nau-
tiloids are known." This view made Nautilus anything but a living fossil.
Millet and Kummel also framed a standard species concept for fossil
nautiloids. They believed that nautiloid genera were highly prone to pro-
ducing new species. By Miller's time, over a thousand post-Triassic-aged nau-
tiloid species had been recognized by paleontologists. Eithet there were an
extraordinary number of these cteatures swimming the world's oceans
through time, or the species concept for nautiloids was exceedingly narrow.