Silvia Gonzalez,fossil researcher,holding a cast of a fossilized sabre-toothed cat's skull. Gonzalez,who studied at the University of Mexico,has worked at the Liverpool John Moores University,UK,since 1994. She researches a wide variety of Quaternary Period deposits and processes. In 2005,she worked on dating and recording human footprints in the Cerro Toluquilla deposits in Mexico,and examining the evidence there for fauna such as sabre-toothed cats. The footprints have been dated to 40,000 years ago,challenging previously accepted theories about when the Americas were colonized |