From: rokimoto557@gmail.com   
      
   On 6/25/2025 11:48 PM, Pro Plyd wrote:   
   >   
   > 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.   
   > ...   
   >   
   >   
   Solanaceae (tomatoes, potatoes, egg plant, deadly night shade) produce a   
   toxin.  It is why peeling potatoes was so popular, and why people that   
   that eat a lot of potatoes can exhibit some of the neurological effects   
   of the toxin.  Cooking reduces the effectiveness of the toxin, but not a   
   whole lot.  I was on a panel discussion on GMO agricultural products   
   when I was a post doc at Michigan State, and we explained why things   
   like putting an extra copy of growth hormone in a fish was not toxic or   
   Round up resistant plants just had a naturally occurring enzyme put in   
   them.  One member of the panel pointed out that natural breeding of crop   
   plants had produced killer crops in the past.  Insect resistant celery   
   and potatoes had been bred by just selecting the most insect resistant   
   plants, and it turned out that they had selected for toxic levels of   
   psoralen in celery that peeled the skin off the farm workers harvesting   
   it in the first test crops, and the potatoes were found to have lethal   
   levels of Solanaceae toxin.  The two examples were relevant because   
   there are no regulations for testing naturally bred crops and both   
   products almost made it out for public consumption.  The celery was   
   abandoned because they could not harvest it.  A commercial product for   
   the potatoes was being created and about to be marketed, but one of the   
   researchers involved in the development of the product had kept working   
   on trying to figure out why it was so insect resistant, and he found out   
   that the potato had toxic levels of the toxin.  They could have poisoned   
   millions because there are no food safety regulations for naturally   
   occurring fruits and vegetables.  The public was worried about one   
   additional possible antigen in soybeans, but they had no qualms about   
   having Kiwi and Star fruit in the supermarkets with thousands of new   
   potential antigens.   
      
   All that is happening with this tomato toxin is that one of the enzymes   
   involved in making the toxin is reverting back to using and producing   
   different stereo isomers of the toxin.  The ancestors had enzymes that   
   produced one stereo isomer (had a specific physical structure), but the   
   enzyme evolved to produce the other stereo isomer, so the toxin had a   
   different shape.  There is no reason why this could not happen because   
   the original enzyme had that activity.   
      
   It is just a reversion of the specific enzymatic activity.   
      
   We discussed chirality in a recent thread, and enzymes choose the   
   chirality.  It isn't any miracle or supernatural phenomena.  Only a   
   molecule of a specific physical structure can fit into a lot of   
   enzymatic active sites, and stereo isomers have different physical   
   shapes even though they have the same elemental composition.   
      
   Ron Okimoto   
      
   --- SoupGate-DOS v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)