The Fruitful Facets of Galton's Polyhedron 379
inherited with ever increasing effect in successive species, occasioning distortions
and retrograde metamorphoses, and finally leading to the extinction of the race"
(1880, p. 14).
Early in his monograph, Hyatt advances the conventional claim of scientific
methodology—that his phylogeny should be judged and accepted on the criterion
of objectivity in research: "These series, having been the result of no preconceived
plan of arrangement as far as the author could judge, were considered to be
approximately natural" (1880, p. 8). Yet Hyatt clearly falls victim to his own
admonition. He did not establish his four-lineage scheme by any principle of
ordering specimens in a manner that could be called "objective" or even bound by
rules independent of his phyletic preferences. Hyatt's scheme of multiple parallel
lineages represents a theoretical construction, dictated by his orthogenetic
conviction about racial life cycles, not a proclamation of nature.
First of all, Hyatt could not separate his lineages with accuracy or confidence.
He uses a method of "eyeballing" and, following the limits of his time, presents no
statistical arguments. Such a failure to quantify need not derail a study in principle;
we need no measuring rods to sort a mixed pile of sparrows and elephants into two
groups. But the Steinheim planorbids interfinger and intergrade in the most
complex manner, both spatially and temporally. The shells occupy a grand clump
of morphospace, with sub-clumps here and there to be sure, but with no clear or
persistent piles. No researcher since Hyatt has been able to specify four distinct
lineages, each maintaining integrity through time.
Second and most important, Hyatt admitted that he could not use the standard
method for establishing lineages—temporal succession in the fossil record. For he
could not identify any clear stratigraphic sequences at all! Following his words
about natural series and lack of preconceptions, Hyatt wrote: "These series...
were assumed to be a reliable basis for working hypotheses, in spite of the fact,
that no certain data with regard to succession in time were obtainable" (1880, p. 8).
How then can phyletic series be established?
Hyatt then admits that, in the absence of stratigraphy, phyletic sequences must
be identified by the expectations of a biological principle—dare we label it a
preconception? —namely, the biogenetic law itself. * Hyatt even permitted himself
to construct phyletic sequences from specimens found on the same bedding plane
if successive stages of a recapitulatory series could be identified: "This assumption
rests largely upon well known laws of heredity, such
*Hyatt's apparent illogic can be comprehended when we recognize that most
scientists of his day regarded the biogenetic law as sufficiently well validated to represent
a fact of nature. Many paleontologists maintained this conviction to quite recent times.
My late senior colleague Bernie Kummel told me of an argument he once had with the
most powerful American paleontologist in the generation just before his own—R. C.
Moore. Kummel, as a young Turk, had disputed the universal validity of recapitulation
over cocktails one evening. Moore slammed down his glass and bellowed: "Bernie, do
you deny the Law of Gravity!"