Dinos lost their teeth to become birds

[Pajarita]

But how did that happen? New study shows that the predentary bone -which is absent in modern birds, of course, and was thought to have completely disappeared through evolution- was actually covered by the rostrum (which is, basically, the beak itself). Is that interesting or is that interesting?!

https://phys.org/news/2019-11-avian-pre ... birds.html

This link tells you about the predentary bone:
https://anatomypubs.onlinelibrary.wiley ... 2/ar.23455