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2. THE NEW SYSTEMS BIOLOGY AND EVO-DEVO
Is evo-devo irrelevant? To some in the NSB, it simply indicates another domain
that NSB can do without. I disagree. So would Eric Davidson and Evelyn Fox
Keller. So, I expect would Carl Woese, a pioneer in the elucidation of the genetic
code and in the phylogeny of very early life. Those who believe they have no
need of evolutionary and developmental perspectives have perhaps been misled
by a common kind of stereotyping of these disciplines.
Many practitioners of evolutionary developmental biology themselves feel that
'evo-devo' lumps diverse practices and perspectives, making them appear more
monolithic than they feel. To some, it seems too skewed towards developmental
genetics as opposed to higher levels of organization such as either morphology
(Love, 2003) or ecology (Gilbert, 2001). Others would worry about the emphasis
on long time scales and correlative emphasis on typological conceptions of
species away from populational variability (Raff, 1996, p. 21). In this stereotypic
image, population genetics, while dynamic, is limited to models of genetic
change in terms of selection coefficients and gene frequencies that abstract away
from physiology and phenotypic organization completely, and the evolutionary
biology of macroevolution is just descriptive and not predictive. No wonder
it seems irrelevant. This stereotyping is inevitable for a new discipline that
articulates so many prior separate areas, and in which most of the practitioners
of one subarea are amateur consumers of most of the others. But unfortunately
it masks a great deal of relevant work.
In fact the confluence of developmental genetics with systems approaches and
a more macroscopic developmental biology, systematics, and comparative stud-
ies has created a new hybrid discipline in which population genetics can move
towards more detailed dynamical models of the phenotype. It is doing so both
synchronically and through its developmental history, and in which systematics
and phylogeny are again used to provide important clues to the organization
of development and the course of evolution, predictively as well as descrip-
tively, as they did in the nineteenth century. At the hands of researchers like
systematist-geneticist-systems biologist Carl Woese, they are redoing the his-
tory of the early origins of life and uncovering surprising things about its nature
(Woese, 2004). These include the initially shocking claims of the endosymbiotic
origins of eucaryotes (Margulis, 1971) and its subsequent elaboration to discover
widespread, now entrenched, symbioses. Morowitz's (1992) claim that large
chunks of metabolism represent preserved chunks of earlier biotic environments
does have things to say about the origins and nature of life, as well as about
its evolution. More recently, Woese's (1998) hypotheses that there was an early
stage in which the ancestors of already distinct lineages interchanged genes far
more readily than later after the development of mitosis solved a remaining
puzzle for systematists with a set of physiological and evolutionary proposals.
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