JEFF E (jaeseca at delphi.com) wrote:
: Whew! You have a much better grasp of this than I do. I'm not sure haw your
: theory difers from evolution as I understand it.
Senapathy's theory is that taxa on about the family level
sprung _fully formed_ from the primordial ooze. This is
radically different from any modern theory of evolution.
Unfortunately, his reasoning is grossly flawed. Furthermore, his posting
title is grossly in contrast to the evidence, for genome projects are
providing much denser information supporting the common origin of
species. In particular, Senapathy claims that the order Mammalia
is an artificial clumping of independently derived lines. He completely
ignores the enormous degree of synteny (conserved chromosomal arrangements)
between mammals. This data has been around for quite a while, but is
now being fleshed out by genome projects.
Just because someone sounds authoritative, has published papers,
and puts out a book doesn't mean they're right. You should reserve
such effusive praise until _after_ you have read the book.
: As a student of molecular
: biology myself I Have found not the theory of evolution hard to grasp, but the
: insistance of evolutionis
:: s to use moleculaar evidence in supporting the theory.
There is an _enormous_ degree of molecular evidence supporting evolution.
Senapathy attempts to simply dismiss the data, but his critique of
sequence comparison is lacking any substance and his statistical arguments
have glaring flaws.
: It seems to me that
: whendealing with a subjest it is wise to go as close to the source of the
: problem as you can get when solving itand this seems to be what you are doing.
: When you bring this before
: an evolutionist however, you will hear about genes being unreliable because of
Gene-based phylogenies are not perfect. Back-mutations are primarily a
problem when dealing with nucleic-acid based phylogenies. Various
phenomena (unequal mutation rates, mistaking paralogs for orthologs or
vice versa, horizontal transfer, convergence, restrictions on sequence
freedom, etc) can complicate a sequence-based phylogeny, but overall
sequence-based phylogenies are useful tools for studying evolutionary
relationships. Furthermore, there are molecular methods which don't
rely so heavily on sequence analysis (which Senapathy also ignored
completely). Pevner, Cedergren, and others have developed methods
based on chromosomal gene orders, and so far these have given results
congruent with sequence-based and morphological taxonomies.
There are several molecular evolution textbooks on the market which
would make a good investment for any molecular biology student.
Department of Cellular and Developmental Biology
Department of Genetics / HHMI
robison at mito.harvard.edu