THE WEEK - Some tomatoes have evolved to possess the characteristics of their ancestors. While it is rare, there have been instances of species displaying traits from further back in evolution. But for the first time, scientists have now been able to prove it through genetic evidence. And there's potential for similar evolutionary changes in the future as the environment changes, even in humans.
Blast from the past
Wild tomatoes on the Galápagos Islands are using chemical defenses that are reminiscent of their ancestors, according to a study published in the journal Nature Communications. The flowering plants 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," said a statement about the study.
Tomatoes are nightshades, like potatoes and eggplants, and nightshades produce alkaloids, which are "bitter toxins that protect the plants against predation," said the BBC. Researchers discovered that tomatoes "on the older eastern islands produced alkaloids found in modern cultivated tomatoes," while tomato plants "on the younger western isles were making unique alkaloids." And the latter alkaloids were largely produced by ancestral tomatoes.
"Some people don't believe in this," Adam Jozwiak, a molecular biochemist at the University of California, Riverside, and the lead author of the study, said in the statement. But the "genetic and chemical evidence points to a return to an ancestral state. The mechanism is there. It happened."