On 7th June 2013 , however , Science Magazine published an article which noted that Pascal Godefroit , the paleontologist who led the team that described Aurornis , reported that he is uncertain if the fossil material came from Liaoning province ' 's 160-million-year-old Tiaojishan Formation , as the information provided by the fossil dealer indicated , or from the province ' 's 125-million-year-old Yixian Formation , which is known to have produced several ancient bird fossils .
On 7th June 2013 Science ( journal ) said that Pascal Godefroit , the paleontologist who led the team that described Aurornis , is uncertain if the fossil material came from Liaoning province ' 's 160-million-year-old Tiaojishan Formation as claimed by the fossil dealer .