Background: Edmund
Ware Sinnott was originally trained in plant anatomy
and was interested in using anatomical features to answer
questions about plant evolution. In fact, many of his
early papers are in collaboration with I.W. Bailey at
the Bussey Institute (Sinnott and Bailey, 1914). However,
early on he was influenced by D’Arcy Thompson’s
(1917) classic, On Growth and Form, and his work soon
shifted to mathematical descriptions of allometric relationships
during plant development (Sinnott, 1921). Now at Barnard
College, Columbia University, the heritability of shape
differences, especially in fruits, moved him into the
genetics of plant development where he focused the rest
of his career (Sinnott, 1935). His opus, Plant Morphogenesis,
was published in 1960, several years after his retirement
from Yale. The present book is a small volume, published
three years later, which was expanded from a Sigma Xi
lecture presented at Yale in 1960. In it Sinnott summarizes
the many of the key concepts from the larger book but
expands on the substance/form correlation.
In the opening chapter he expands on the significance of
form: what it is and why it is important. He acknowledges
the contemporary molecular work (the decade after Watson
and Crick) with the interest of a geneticist concerned with
controlling cell differentiation, but cautions that the organism
is not merely an aggregation of cells. Rather, form may be
based on a larger, organismal whole.
Throughout the book Sinnott
reminds us that biophysical interactions may be as important
as
biochemical ones. Polarity,
symmetry, and spirality are unifying features of morphogenesis
with solid physical as well as physiological bases. Furthermore,
he spends considerable time considering the interaction of
genes and the environment and is concerned with identifying “norms.” Several
times he emphasizes that the morphogenetic repertoire of
each level in the structural hierarchy is greater than is
usually displayed and this is the basis of evolution. Thirty-some
years ago this book was an excellent introduction to plant
morphogenesis; it remains a prescient introduction to plant
evo-devo.
Edmund W. Sinnott, and Irving
W. Bailey. 1914. Investigations on the phylogeny of the
angiosperms.
3. Nodal anatomy and
the morphology of stipules. American Journal of Botany 1(9):
441-453. article at JSTOR
Edmund W. Sinnott. 1921.
The relation between body size and organ size in plants.
American
Naturalist 55(640): 385-403. article
at JSTOR
Edmund W. Sinnott. 1935. Evidence
for the existence of genes controlling shape. Genetics 20(1):
12-21. article
in pdf format
Edmund W. Sinnott. 1960. Plant
Morphogenesis. McGraw-Hill, New York. 550 pages.
D’Arcy Thompson. 1917.
On Growth and Form. Cambridge University Press, Cambridge.
submitted by: Marshall
Sundberg
