Hankering for a taste of the Stone Age? Too bad, because no one’s currently allowed to eat the giant, delicious-looking meatball made from lab-grown woolly mammoth meat that was unveiled by the Australian cultured-meat startup Vow in the Netherlands on Tuesday. “We’re definitely not allowed to say that anyone has tasted the mammoth meatball,” James Ryall, chief scientific officer for Vow, told The Times of London. Professor Ernst Wolvetang, a stem cell biologist involved in making the meatball, explained to The Guardian, “We haven’t seen this protein for thousands of years. So we have no idea how our immune system would react when we eat it.” The idea to create the forbidden meatball came after researchers struck out on a bid to create a “dodo nugget,” with the requisite DNA sequence not available to Wolvetang’s team, according to The Times. Genetic information from the extinct mammoth was publicly available, however. “This is not an April Fool’s joke. This is real innovation,” Vow founder Tim Noakesmith said on Tuesday, according to the Associated Press, which also reported that the meatball “smelled good.”