Resumo de The Ovary Of Eve - CLARA PINTO-CORREIA

Reproduction has always been a controversial topic, and the
scientific debates over it in early modern Europe
were no exception. From the middle of the seventeenth century to the middle of
the eighteenth, the dominant theory was that of preformation, which
postulated that organisms contained all their future descendants, folded up or
encased in increasingly miniature forms. Preformation eventually lost out to
epigenesis, and has received unfairly negative publicity ever since.

In The Ovary of eve Pinto-Correia takes as her subject not the
battle between preformation and epigenesis, but preformation in its own right,
and in particular the debates between the ovists (who argued that the organism
was encased in the egg) and the spermists (who favored the sperm as a
container). Inspired by Stephen Jay Gould (who contributes a foreword), she
exhibits a similar breadth of learning. Her account ranges not just over the
history of embryology but over science more generally, and over the broad sweep
of culture and ideas.

Malebranche and Swammerdam were the founding "fathers" of ovism.
In their studies of frogs and chickens and insects, they thought they could see
the future parts of the adult folded up inside the egg (Swammerdam probably
discovered insect imaginal disks but interpreted them wrongly). Prominent later
ovists included von Haller, Bonnet, and Spallanzani. But the connection of eggs
with Reproduction is quite obvious, and ideas about it can be traced back to
the Egyptians and the Greeks, as well as cross-culturally.

Spermism originated later, with the microscope and the work of van
Leeuwenhoek and Hartsoeker. Later spermists included Astruc, Boerhaave, and
d''Agoty. Sperm were seen as little animals, as tadpoles or worms, and hence
held in low regard by many. Another problem spermism faced was how to explain
why so many sperm were wasted. In the 18th century this problem was worsened by
a growing hysteria over masturbation ("the great fear"), started by
the pamphlet Onania and propelled by Tissot''s campaigns. There was
also a reluctance to accept a physical role for sperm in reproduction, with
many assigning them a spiritual role instead, acting through an immaterial aura
seminalis. This had parallels with the doctrines of the Immaculate
Conception and the Holy Spirit.

Commonly attributed to the spermists (as a form of mockery) is a
"wounded warrior" theory, in which conflict between sperm is
responsible for the birth of monsters. This would have been a powerful argument
for spermism if monsters had been considered a major problem for preformation.
But while teratology (the study of monsters) was of widespread interest, the
difficulties posed by monsters (and by the ability of some organisms to
regenerate from parts) afflicted epigenesis and preformation alike. And in fact
the "wounded warrior" idea was retrospectively written into the
history of spermism.

The use of the word "homunculus" to describe human-like sperm
(commonly accompanying drawings attributed to Hartsoeker) has a similar
history. The word had long-standing negative associations, resulting from its
connection with attempts to create life, so it would have been surprising if
the spermists had chosen to use it. In fact they avoided it quite scrupulously,
and its association with spermism was a creation of later writers.

In the mid-eighteenth century, Buffon and Needham revived the theory of spontaneous
generation; this time it took the form of a Vegetative Force. In response Spallanzani
carried out a long series of experimental tests of the role of sperm in
reproduction (including the famous "frogs in boxer shorts"
experiment), in the process making important advances in experimental technique
(among them the first artificial fertilisations). But Spallanzani remained an
ovist, despite his demonstration of a crucial role for sperm in reproduction.

One advantage for ovism lay in thepe of the egg. The sphere represented
perfection and was therefore highly favored ? as can be seen from the history
of theories of planetary motion. But a countering disadvantage was that eggs
came from the female of the species, consistently considered inferior in the
West, along with the left side.

Numerology already had a long history in Western culture, going back to the
Pythagoreans, but the invention of the microscope and the discovery of the very
small ushered in a period of fascination with the resulting large numbers.
Hairs, pores, insect eyes, and other body parts were counted and their numbers
calculated with. But preformation offered a particularly fertile field for the
numerically minded: immense numbers of generations and encased organisms, and
geometric progressions in development.

The debate continues today: some of the issues argued over by the
preformationists still bedevil modern developmental biology. Their traces can
be seen in the flaws in the science of Jurassic Park
and in the difficulties faced in cloning vertebrates and especially mammals (an
area in which there have been notable achievements since The Ovary of Eve
was printed). The turn of the century debate between Hertwig and Weissmann (a
preformationist) and the rise of genetics (traditionally identified with
preformationism) illustrate the ongoing complexities of the subject.

The story of preformation is a grand tale, and Pinto-Correia gives it its
full due. She often digresses ? she includes a long account of astrological and
metallurgical sex symbolism, for example ? and she includes comparisons with
ideas about reproduction from non-European cultures, but everything is woven
together into a unified picture. The result is a tour de force, a
penetrating portrait of an entire scientific milieu. The Ovary of Eve
will be appreciated by many who have never thought about biology, not just by
historians of embryology and reproductive biology.

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