Meet the potato’s unexpected ancestor: the tomato.
That’s right, a fruit. Potatoes and tomatoes don’t look alike, smell alike or taste alike, but in a study published Thursday in the journal Cell, scientists said that the potato evolved from a tomato ancestor around 9 million years ago.
“We’ve finally solved the mystery of where potatoes came from,” corresponding author Sanwen Huang of the Chinese Academy of Agricultural Sciences said in a news release.
The origin of the modern potato has puzzled scientists for years. In terms of appearance, potatoes resemble a species from Chile called Etuberosum, with one crucial difference: Etuberosum don’t produce the starch-rich tubers. That’s where the tomato comes in.
While tomatoes don’t have tubers, the ancient tomato did provide a crucial gene that, when mixed with the genetics of Etuberosum, told the modern potato to form tubers, according to the researchers. The SP6A gene from the tomato parent tells the potato plant to make tubers, while the IT1 gene from Etuberosum assists in controlling the growth of the underground stems that form tubers. Both pieces were needed to create the potato that’s known and loved today.
Yuxin Jia and Pei Wang 
“Our findings show how a hybridization event between species can spark the evolution of new traits, allowing even more species to emerge,” Huang said.
The research team analyzed 450 genomes from cultivated potatoes and 56 of the wild potato species during the study.
“Wild potatoes are very difficult to sample, so this dataset represents the most comprehensive collection of wild potato genomic data ever analyzed,” said the paper’s first author, Zhiyang Zhang of the Agricultural Genomics Institute at Shenzhen.
Outside of the ancestry, there’s also a linguistic similarity, according to Merriam-Webster.
“The word ‘tomato’ started out as ‘tomate’ and came from the Nahuatl word ‘tomatl.’ Since the potato had been introduced to the English some decades earlier, the word evolved to mimic the form of ‘potato’ — hence the spelling ‘tomato,'” the dictionary notes.