From Tomato to Tuber: How a 9-Million-Year-Old Plant Romance Created the Potato

Imagine a world where fries, mashed potatoes, and potato chips didn’t exist. Surprisingly, this staple crop, which feeds billions, owes its existence to an unlikely love story between a wild tomato and a potato-like plant 9 million years ago. A groundbreaking study published in 2025 in Cell reveals that the modern potato emerged from a natural hybridization event between ancestors of the tomato (Solanum lycopersicum) and a South American plant called Etuberosum. This ancient crossbreeding, occurring as the Andes Mountains rose, sparked the evolution of the tuber—a nutrient-packed underground structure that defines the potato. This article dives into the science behind this discovery, exploring how this hybridization led to one of the world’s most important crops, its impact on global agriculture, and what it means for future food security.

The Mystery of the Potato’s Origins

Potatoes (Solanum tuberosum) are a global dietary cornerstone, ranking as the third most important staple crop after rice and wheat. Yet, their evolutionary origins puzzled scientists for decades. Above ground, potato plants resemble Etuberosum, a group of three South American species in the Solanum genus, but Etuberosum lacks tubers. Genetically, potatoes share similarities with tomatoes, which also lack tubers. This contradiction—looking like one plant but genetically closer to another—left researchers stumped. A 2025 study led by Sanwen Huang at the Chinese Academy of Agricultural Sciences finally cracked the case, revealing that potatoes arose from a hybridization event between tomato and Etuberosum ancestors around 8–9 million years ago.

[](https://www.livescience.com/planet-earth/evolution/tomatoes-randomly-mated-with-another-plant-9-million-years-ago-the-result-potatoes)[](https://scienceblog.com/potatoes-came-from-tomatoes-9-million-years-ago/)

How Hybridization Created the Potato

Hybridization occurs when two different species interbreed, combining their genetic material to create offspring with new traits. In this case, the tomato and Etuberosum lineages, which diverged from a common ancestor 13–14 million years ago, crossed paths in the Andes. Likely pollinated by bees, these plants produced a hybrid offspring that became the potato lineage, known as Petota, which includes 107 wild species and the cultivated potato. The key to this new lineage was the formation of tubers, a trait neither parent possessed alone. The study identified two critical genes: SP6A from the tomato lineage, which acts as a “master switch” to initiate tuber formation, and IT1 from Etuberosum, which controls the growth of underground stems into tubers. This genetic synergy created a new organ, enabling the potato to store nutrients and water, a game-changer for survival in harsh environments.

[](https://www.livescience.com/planet-earth/evolution/tomatoes-randomly-mated-with-another-plant-9-million-years-ago-the-result-potatoes)[](https://www.theguardian.com/science/2025/jul/31/potato-evolved-from-tomato-ancestor-researchers-find)

Why Tubers Made Potatoes a Global Success

The emergence of tubers gave potatoes a unique advantage. Unlike their tomato and Etuberosum ancestors, which relied on seeds for reproduction, potato tubers allowed asexual reproduction—new plants could sprout directly from tuber buds. This trait was critical during the rapid uplift of the Andes 6–10 million years ago, when cold, dry conditions challenged plant survival. Tubers stored energy and water, enabling potatoes to thrive in diverse habitats, from grasslands to alpine meadows. This adaptability fueled an “explosion” of over 100 wild potato species, as noted by Huang. The potato’s resilience also made it a dietary mainstay when humans domesticated it 7,000–10,000 years ago in the Andes, later spreading globally via Spanish explorers in the 16th century.

[](https://scienceblog.com/potatoes-came-from-tomatoes-9-million-years-ago/)[](https://www.theguardian.com/science/2025/jul/31/potato-evolved-from-tomato-ancestor-researchers-find)

The Science Behind the Discovery

Unraveling the potato’s origins required cutting-edge genomic analysis. The research team analyzed 450 genomes, including 101 from the Petota lineage, 15 from tomatoes, and 9 from Etuberosum, creating the most comprehensive wild potato genomic dataset to date. “Wild potatoes are very difficult to sample, so this dataset represents the most comprehensive collection of wild potato genomic data ever analyzed,” said lead author Zhiyang Zhang. By constructing over 3,000 phylogenetic trees, the team confirmed that potato genomes are a stable mosaic of tomato and Etuberosum DNA, with 50.66% of trees showing tomatoes as a sister lineage to Petota. CRISPR knockouts further validated the roles of SP6A and IT1, showing that disrupting these genes prevented tuber formation or caused abnormal growth.

[](https://scienceblog.com/potatoes-came-from-tomatoes-9-million-years-ago/)[](https://gizmodo.com/potatoes-evolved-from-tomatoes-study-reveals-2000637125)

Environmental and Evolutionary Context

The timing of this hybridization was no accident. Around 8–9 million years ago, the Andes Mountains were undergoing rapid uplift, creating new ecological niches. The cooling climate of the late Miocene epoch favored plants that could store resources underground. The potato’s tuber, a product of genetic mixing, allowed it to colonize high-altitude, cold, and dry environments where tomatoes (preferring warm, dry conditions) and Etuberosum (thriving in cold, wet climates) struggled. This “best of both worlds” trait, as botanist Sandra Knapp described, gave potatoes a wider ecological range, leading to their diversification across Central and South America.

[](https://www.sciencenews.org/article/potatoes-roots-ancient-tomatoes-origin)[](https://cosmosmagazine.com/science/biology/potato-tomato-species-hybridisation/)

Implications for Modern Agriculture

Understanding the potato’s hybrid origins has profound implications for agriculture. Potatoes produce 375 million tonnes annually but face challenges from pests, diseases, and climate change. The study’s insights could guide breeding programs to create more resilient varieties. For example, reintroducing tomato genes like SP6A could enable seed-based reproduction, increasing genetic diversity and disease resistance compared to vegetative propagation (planting tuber pieces), which produces genetically identical crops vulnerable to diseases. Researchers are also exploring “tomtatoes”—plants combining tomato fruits and potato tubers—to enhance crop efficiency. “Our primary focus is on translational applications in potato breeding, particularly addressing deleterious mutations,” said Zhang, highlighting the potential to engineer hardier crops.

[](https://www.washingtonpost.com/science/2025/07/31/potato-tomato-evolution-study-hybridization/)[](https://newatlas.com/biology/how-our-modern-day-potato-evolved-from-tomatoes-9-million-years-ago)

Challenges and Future Research

While the study solves the potato’s origin mystery, questions remain. Hybrid offspring are often sterile, yet the potato lineage regained sexual reproduction over time, a process scientists are still investigating. The ancient tomato and Etuberosum ancestors no longer exist, so researchers rely on genetic signals in modern plants to reconstruct the past. Future studies aim to explore how tuber-related genes interact and whether they can be manipulated to improve crop resilience. For instance, introducing potato genes into tomatoes could create plants that produce both fruits and tubers, maximizing yield in limited spaces. These experiments, while early-stage, highlight the creative potential of hybridization.

[](https://www.nytimes.com/2025/07/31/science/evolution-agriculture-tomatoes-potatoes.html)[](https://www.theguardian.com/science/2025/jul/31/potato-evolved-from-tomato-ancestor-researchers-find)

Practical Takeaways for Readers

The potato’s story is more than a scientific curiosity—it’s a lesson in nature’s ingenuity. Here’s how this knowledge applies to daily life:

• Appreciate Potatoes’ Versatility: From fries to gnocchi, potatoes’ nutrient-storing tubers make them a cheap, calorie-rich staple. Try diverse varieties like purple or fingerling potatoes to explore their biodiversity.
• Support Sustainable Agriculture: Choose locally grown potatoes to reduce environmental impact, as their hardiness suits various climates.
• Explore Culinary Pairings: Next time you pair ketchup with fries, remember their ancient connection—tomatoes and potatoes are family!

Fun Fact: The word “tomato” derives from the Nahuatl word “tomatl,” and “potato” evolved linguistically to mimic it, reflecting their shared heritage.

[](https://www.cbsnews.com/news/potato-tomato-origin-ancient-interbreeding-hybridization-study/)

Conclusion

The potato’s origin story is a testament to nature’s ability to innovate through hybridization. Nine million years ago, a chance encounter between a tomato and an Etuberosum plant, facilitated by a bee and the rising Andes, birthed a new lineage with a revolutionary trait: the tuber. This adaptation not only ensured the potato’s survival but also made it a global staple, feeding billions today. As researchers like Sanwen Huang note, “We’ve finally solved the mystery of where potatoes came from.” This discovery not only deepens our understanding of evolution but also opens doors to breeding resilient crops for a changing world. So, next time you enjoy a potato dish, thank its ancient tomato ancestor for sparking one of history’s most delicious accidents.

[](https://x.com/AFP/status/1950946514311778379)[](https://scienceblog.com/potatoes-came-from-tomatoes-9-million-years-ago/)

References

1. Zhang, Z., et al. (2025). Ancient hybridization underlies tuberization and radiation of the potato lineage. Cell, 187(16), 4235–4247. Link

[](https://scienceblog.com/potatoes-came-from-tomatoes-9-million-years-ago/)

2. Knapp, S., et al. (2025). Hybridization and the origin of the potato. Scientific American. Link

[](https://www.scientificamerican.com/article/how-the-potato-got-its-start-nine-million-years-ago-thanks-to-a-tomato/)

3. Huang, S., et al. (2025). Potato evolution from tomato and Etuberosum. Live Science. Link

[](https://www.livescience.com/planet-earth/evolution/tomatoes-randomly-mated-with-another-plant-9-million-years-ago-the-result-potatoes)

4. Charkowski, A. (2025). Potato’s evolutionary origins. CNN. Link

[](https://amp.cnn.com/cnn/2025/07/31/science/potato-evolution-origins-tomato)