Page "Triceratops" Paragraph 19

For many years after its discovery the evolutionary origins of Triceratops remained largely obscure.

In 1922 the newly discovered Protoceratops was seen as its ancestor by Henry Fairfield Osborn, but many decades passed before additional findings came to light.

However, recent years have been fruitful for the discovery of several dinosaurs related to ancestors of Triceratops.

Zuniceratops, the earliest known ceratopsian with brow horns, was described in the late 1990s, and Yinlong, the first known Jurassic ceratopsian, in 2005.