The earliest fossil bird is known from two partial skeletons found in Texas, USA in rocks dating from 220 million years ago. Named Protoavis texensis in 1991, this pheasant-sized creature has caused much controversy by pushing the age of birds back many millions of years from the previous record – that of the more familiar Archaeopteryx lithographica found in Jurassic sediments in Germany. It is still unclear whether Protoavis will be widely accepted as a true bird, making Archaeopteryx, the 153-million-year-old crow-sized flier, the earliest unambiguous fossil bird.