From Bozeman, Mont., at the 61st annual meeting of the Society for Vertebrate
Newly discovered fossil skulls of juvenile Triceratops may help reveal how the dinosaurs grew their three trademark horns.
Until recently, scientists had unearthed the fossil skulls only of adult
Triceratops, with the exception of a 28-centimeter-long skull that likely belonged
to a young animal, says Mark B. Goodwin, a paleontologist at the University of
California, Berkeley. That small specimen indicated that the horn growing up from
the end of the animal's snout started out as a separate bone that later fused to
the skull and continued to grow.
In the past 3 years, Goodwin and his colleagues have excavated the skulls of a few
juvenile Triceratops from the Hell Creek Formation in eastern Montana. The horns