Scientists Say Tomatoes in Galapagos are De-evolving
Posted on June 24, 2025
Scientists at the University of California, Riverside say tomatoes on the younger, black-rock islands of the Galápagos archipelago are de-evolving. The photograph shows de-evolved tomato species from the Galápagos.
These tomato plants are shedding millions of years of evolution and reverting to a more primitive genetic state. This state resurrects ancient chemical defenses. It includes a toxic molecular cocktail that hasn't been seen in millions of years, one that resembles compounds found in eggplant, not the modern tomato.
The researchers analyzed more than 30 tomato samples collected from distinct geographic locations across the islands. The tomato plant survey revealed a striking pattern. Tomatoes on older, more stable eastern islands have modern tomato chemistry, while those on the harsher, barren western islands have resurrected the ancestral defense. The scientists suspect these revived alkaloids offer better protection in tough conditions. This shows how changing environments can reopen evolutionary dead ends. The researchers found the switch to the ancient defense hinges on just four amino-acid tweaks in a single enzyme.
Dr. Adam Jozwiak, the molecular biochemist from the University of California, Riverside, says, "If you change just a few amino acids, you can get a completely different molecule. That knowledge could help us engineer new medicines, design better pest resistance, or even make less toxic produce."
The concept is controversial and Jozwiak says, "Some people don’t believe in this. But the genetic and chemical evidence points to a return to an ancestral state. The mechanism is there. It happened."
He also says it could happen to humans: "I think it could happen to humans, It wouldn't happen in a year or two, but over time, maybe, if environmental conditions change enough."
The research was published in the journal, Nature Communications.
Image: Adam Jozwiak