Research & Collections

Siats meekerorum

What's cool about our new dinosaur, Siats meekerorum?

Siats is a RARE discovery and a first record

  • Siats is only the second carcharodontosaur ever discovered in North America.
  • And it is the first to be discovered here in 63 years: (Acrocanthosaurus, named in 1950, is the other member of the group from North America). 
  • Siats is the first Neovenatorid dinosaur ever found in North America.
    • Other members of this group are known from Europe, South America, China, Japan, and Australia.  The group was unknown in North America until now.

Siats was a giant

  • Siats is one of the top three largest predatory dinosaurs ever discovered in North America, second only to Acrocanthosaurus (no.2) and T. rex (no.1).  An adult Siats was probably as big as Acrocanthosaurus but we can’t say for sure.
  • Siats tipped the scales at over 4000 kg (>8600 lbs) and again our specimen is a juvenile, so adult mass/size would be significantly larger.

Siats helps us understand the evolution of apex (top) predators in the Cretaceous

  • Giant carcharodontosaurs like Siats lived alongside small tyrannosaurs in North America.  This is the first time we have evidence of both groups in the same ecosystem.  Their large size would have kept tyrannosaurs from assuming top predator roles until they went extinct, allowing tyrannosaurs to evolve into the megapredators that we know and love.
  • Siats demonstrates that carcharodontosaurs, and even more importantly allosaurs, lived in the Late Cretaceous of North America. (They were previously thought to have died out in the Early Cretaceous.)

Siats within its ecosystem, eating an Eolambia (an iguanodontian) and intimidating early, small-bodied tyrannosauroids. Illustration by Julio Lacerda, copyright Lindsay Zanno. (Click to enlarge.)

Siats meekerorum illustration by Jorge Gonzalez. (Click to enlarge.)

Press Release


Siats Discovery Announcement Video

Untamed Science Video

NC State University Video