Dated at 90 milllion years old, the fossils are the earliest evidence of a flying dinosaur.
Dated from 90 milllion years old, the fossils are the earliest evidence of a flying dinosaur.
Dated at 90 milllion years old, the fossils are the earliest evidence of a flying dinosaur.
Dated from 90 milllion years old, the fossils are the earliest evidence of a flying dinosaur.
The participle "dated" idiomatically takes the preposition "at." The structure dated at [time] gives the age or time of occurrence of something.