Therefore, soy-beans could not evolve
a genotype with the same phenotypic effect.
Glyphosate resistance has evolved
in other plant species. Wikipedia lists rigid ryegrass (Lolium rigidum),
giant ragweed, Palmer amaranth, Conyza bonariensis, Conyza canadensis, Johnson
grass (Sorghum halepense), and Boliviana negra, also known as
"supercoca"; WP also refers to many other species without naming them. There's
no need to dig any deeper, even though it is Wikipedia. There is no indication
that Monsanto, rather than nature, caused any of these mutations.
Monsanto,
it appears, used a technique modelled on natural processes to create the
glyphosate-resistant genotype. The natural process of transfection is random,
because of the need for the process agent (virus, chemical, mechanical) and the
insertion capsid to be in proximity to the transfectee. It's rare in nature,
luckily enough, in that it doesn't happen to many transfectees, but all species
that have been examined — including H. sap. sap. — have shown
germ-cell transfection to be one of nature's major mutagenic processes. Yes,
your own genotype, and mine, have been affected by multiple similar
incidents.
No Roundup, no gene.
It's not clear to
me, right now, whether glyphosate resistance is from a gene or another organelle
like a mitochondrion; but it really doesn't matter. I'll honour the use of
'gene' to describe its source and propagation.
Evolution works by the
selective survival of certain genotypes within the environment their phenotypes
find themselves in. In an environment where glyphosate is prevalent, a
glyphosate-resistance gene survives and is propagated readily. In the absence
of glyphosate, the gene's survival depends on its other contributions to the
phenotype's survival.
WP reports that at least some of the natural
glyphosate-resistant phenotypes are less robust that the glyphosate-vulnerable
ones. This hints that the phenotype's alternative amino-acid synthesis pathways
are usually not as effective as the glyphosate-vulnerable pathways. To the
extent that this is the case, then we can expect "no Roundup, no gene," at least
in the long term. That's nature for you.
---
--Bill. NAL: question the
answers, especially mine.
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