The plant family of tomato is much older than previously thought. Higher developed nightshade plants were apparently spread 52 million years ago on the primeval continent Gondwana, reports the journal Science.
The nightshade family includes more than 2,400 species, including many culturally and economically important representatives such as tomato, potato and pepper. Now scientists from Pennsylvania State University in Patagonia have found fossils of plants that have characteristic features of the genus Blasenkirschen( Physalis) from this plant family. To the genus Physalis belong for example the well-known Kapstachelbeere( Andean berry) and the Tomatillo, which resembles a green, still unripe tomato. It is typical that the fruits are surrounded by a lantern-like chalice.
The remains of the former Physalis plants were discovered during excavations at Laguna del Hunco in Argentina. Even the berry and the paper-like, five-pointed pericarp can be recognized. After rock investigations, the two finds are 52 million years old. At that time, the area was a temperate rainforest and part of the primeval southern continent of Gondwana, which included the adjacent land masses of South America, Antarctica and Australia.
The scientists have closely studied the fossil fruits and compared them with living relatives. According to their findings, these are the first fossil fossils worldwide and the first fossil fruits of the nightshade family. The genus Physalis is at the top of the evolutionary family tree of the nightshade family. This means that the entire family must be much older than 52 million years old. Also, the fanning of species in the course of evolution must be reconsidered due to the new findings, the scientists say. Heike Kreutz, bzfe.de