Big bodied animals are often fossilized without their skulls
because the skull bones are frequently crushed and lost in time. The long standing confusion over what the Apatosaurus skull
actually looked-liked is a classic example. Hussam Zaher and colleagues have
now described Tapuiasaurus macedoi a
sauropod dinosaur and a member of the titanosaur clade. The description is
based upon an almost complete skeleton, including a well preserved skull
estimated to be 125-112 MYA. The skull resembles those of other titanosaurs
such as Rapetosaurus from Madagascar and Nemegtosaurus from Mongolia, because it has an
elongated snout, a nasal opening at the level of the eyes, and narrow crowns on
its teeth. However, Tapuiasaurus predated
these dinosaurs by at least 30 million years, suggesting the skull shape of the
Late Cretaceous titanosaurs evolved much earlier than previously thought. The complete article can be found on-line.
Zaher H, Pol D, Carvalho AB, Nascimento PM,
Riccomini C, Larson P, Juarez-Valieri RD, Pires-Domingues R, da Silva NJ(Jr.)
& Campos DA. 2011. A Complete Skull of an Early Cretaceous Sauropod and the
Evolution of Advanced Titanosaurians. PLoS ONE 6(2): e16663. doi:10.1371/journal.pone.0016663