I am a molecular biologist, but not one who
studies molecular evolution, so I ask the following
question of the folks here. In reading a review, I
came across the following statement: "The issue of
the evolution of the [mammalian] metalloproteinase
family can eventually be resolved by characterizing
the MMPs in more primitive species." I do not doubt
that we can learn valuable lessons from such analysis.
However, because of the lack of linear evolution from
"more primitive" extant species to so-called "higher
species," I am not convinced that the issue of evolution
(per se) of a gene family can be resolved in this manner.
That is, these genes have been evolving for millions of
years in all species; therefore, we cannot conclude that
gene A in humans derived from gene B in, say, fish. That
they evolved from a common ancestor may be probable,
but the linear relation implied by the quote above
disturbs my sensibilities. Can somebody with a better
evolution background either confirm or deny my suspicions
that the quote is more than a little specious?
sticknbd at miranda.cc.vanderbilt.edu