The fruit synonymous with summer, plump tomatoes, descended from tiny wild ancestors. The genetic footprints left by that journey recently were traced by an international team of plant biologists. The deciphered DNA map of the tomato and its wild relatives points to ways that the fruit could be bred to survive in harsh, desert conditions, which may become more common as climate change reshapes the world.
Domesticated tomatoes' (Solanum lycopersicum) DNA showed signs of the artificial selection and breeding efforts that brought about their significantly larger, redder fruit compared with wild relatives. However, the domestication of the tomato came with genetic drawbacks.
Centuries ago, the tomato appeared on European tables after Spanish conquistadors brought the plant from its Western Hemisphere homeland. Only a few plants and seeds made the journey across the Atlantic, which created what geneticists call a bottleneck, or a serious reduction in population that resulted in lower genetic diversity.