Re: Reverse evolution in Galapagos tomato

On Wed, 25 Jun 2025 22:48:40 -0600, the following appeared
in talk.origins, posted by Pro Plyd
<invalide@invalid.invalid>:

>
https://phys.org/news/2025-06-tomatoes-galpagos-quietly-de-evolving.html
>
On the younger, black-rock islands of the
Galápagos archipelago, wild-growing tomatoes
are doing something peculiar. They're shedding
millions of years of evolution, reverting to a
more primitive genetic state that resurrects
ancient chemical defenses.
>
These tomatoes, which descended from South
American ancestors likely brought over by birds,
have quietly started making a toxic molecular
cocktail that hasn't been seen in millions of
years, one that resembles compounds found in
eggplant, not the modern tomato.
>
In a study published recently in Nature
Communications, scientists at the University of
California, Riverside, describe this unexpected
development as a possible case of "reverse
evolution," a term that tends to be controversial
among evolutionary biologists.
>
That's because evolution isn't supposed to have
a rewind button. It's generally viewed as a
one-way march toward adaptation, not a circular
path back to traits once lost. While organisms
sometimes re-acquire features similar to those
of their ancestors, doing so through the exact
same genetic pathways is rare and difficult to
prove.
>
However, reversal is what these tomato plants
appear to be doing.
>

Interesting, but if the genetic structure was once there to
produce these toxic molecules, perhaps it was "switched off"
when no longer needed (i.e., converted to "junk DNA") and
now has been reactivated due to environmental factors?

>

--

Bob C.

"The most exciting phrase to hear in science,
 the one that heralds new discoveries, is not
 'Eureka!' but 'That's funny...'"

- Isaac Asimov