These findings were artificial in the sense that the prompting signal was experimentally administered nonetheless, they were significant in showing that a chicken's jaw could produce teeth if specific conditions were present.ĭespite this discovery, no one had yet demonstrated that chickens could develop teeth without external cues. As a result, toothlike structures grew, and other tooth markers were expressed (Chen et al., 2000). Since then, however, many investigators have unearthed molecular evidence that the genes involved in odontogenesis (tooth development) are indeed retained in chickens.Ī primary step in reaching this conclusion occurred when researchers exposed chick jaws to certain proteins known to cue tooth development. Hilaire was the first scientist to publish the observation that some bird embryos exhibited evidence of tooth formation, but his contemporaries considered his work flawed.

Even though birds lost teeth as physical structures between 60 and 80 million years ago, several studies have shown that those tissues within birds that would normally produce teeth still retain the potential to do so.