Patagonian Galls (IMAGE) University of Wisconsin-Madison Caption Patagonian galls such as these harbor the cold-adapted yeast Saccharomyces eubayanus, a parent of the hybrid yeast used to make lager or cold-brewed beer. A field survey has confirmed that the parent yeast S. eubayanus, which somehow made its way to Bavaria 500 or so years ago, is easily isolated in Patagonia. A Wisconsin team recently isolated the yeast, although at low frequency, near Sheboygan, Wis. -- the first time it has been found in nature in North America. Credit Diego Libkind, Institute for Biodiversity and Environment Research, Bariloche, Argentina Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.