Fossil finds in Patagonia
The tomato plant family is much older than previously thought. More sophisticated nightshade plants appeared to be widespread on the primeval continent of Gondwana 52 million years ago, reports the scientific journal Science.
The nightshade family includes more than 2,400 species, including many culturally and economically important representatives such as tomato, potatoes and peppers. Now scientists from Pennsylvania State University have found fossils of plants in Patagonia that have characteristic features of the genus of the common cherry (Physalis) from this plant family. The well-known Cape gooseberry (Andean berry) and the Tomatillo, which resembles a green, still unripe tomato, belong to the genus Physalis. It is typical that the fruits are surrounded by a lampion-like chalice.
The remains of the earlier Physalis plants were discovered during excavations at the Laguna del Hunco in Argentina. You can even see the berry and the paper-like, five-lobed fruit skin. According to rock investigations, the two finds are 52 million years old. At the time, the area was a temperate rainforest and part of the primeval southern continent of Gondwana, which included the adjacent landmasses of South America, Antarctica and Australia.
The scientists examined the fossil fruits closely and compared them with living relatives. According to their results, they are the first Physalis 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 significantly older than 52 million years old. The diversification of species in the course of evolution must also be reconsidered based on the new findings, the scientists believe. Heike Kreutz, bzfe.de