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or disproved, his comments on the function of ammonite septa in strength-
ening the shell stand shining apart. They were largely accepted up to the
present day.
Does more complex mean stronger?
In the early 1900s new breed of paleontologist was emerging, investigators
concerned not only with what fossils could say about time but with what
they could reveal about themselves and the world they lived in. The analy-
sis of function began to be taken seriously. Foremost among this new wave
were Germans, most from the University town of Tubingen. Tubingen al-
ready had a long association with paleontology, having been the home of
two of the greatest of all early paleontologists, Albert Quendstedt and his re-
markable pupil, Albert Oppel. But these nineteenth-century paleontologists
were concerned with biostratigraphy, whereas their early twentieth-century
descendants thought more about mode of life, form, and function. Because
they were surrounded by rocks rich in fossil ammonites, it is no surprise that
many of these students began to study ammonite paleobiology.
One of the most brilliant of these students was A. Pfaff, who made the
most detailed functional study of ammonites up to that time. He noted that
ammonites with compressed shells had more crenulations than those with
rounder shell cross sections. From this observation he deduced that the flat-
ter shell regions were inherently weaker (because of their lack of curvature)
and would therefore need more shell buttressing. Rounder shells would be
supported by the curvature of the shell and would require less buttressing—
and thus less complex sututes.
Pfaff and others of his time were also well aware of another curious
facet of ammonite sutures: Over the long, 360-million-year history of the
group, the septal sutures just seemed to keep getting more complicated. Am-
monites didn't show a greater number of sutures over time—in other words,
their shells did not get packed with more and more septa—but those septa
that were present became more sinuous in theit appearance until, by the
Cretaceous Period, they made the most complicated river course seem straight
