October 30. A big predator

Where there are herbivores, there are carnivores. The gigantic Sauropods of the Jurassic must have been a feast for the gigantic carnivorous dinosaurs – whether they killed them or scavenged on dead bodies. Just this year, 2014, a new species of predatory dinosaur was described from Europe, and it may be the largest Jurassic predator known.  

Torvosaurus in Museum of Ancient Life in Lehi, Utah, U.S.A.
Photo by leon7 used under Creative Commons license 

Portugal has late Jurassic rocks containing many of the same dinosaur species found in the Morrison Formation of the western United States. The Jurassic Lourinhã Formation was laid down in a flat coastal plain along the shore of the newly formed Atlantic Ocean. Rifting here began in the Triassic, as Iberia began to pull away from Newfoundland. The rift that ultimately became the Atlantic Ocean was established a bit to the west, so this area remained a low-lying zone near the margin of the ocean. The setting was much like that of the Morrison Formation, although the Morrison was along the shores of an inland sea, while the Portuguese rocks formed along a real ocean coastline. 

In both the Morrison and in Portugal, the top predator was a dinosaur of the genus Torvosaurus – a carnivore that at a glance looks a lot like Tyrannosaurus, which is a Cretaceous dinosaur. Torvosaurus was about 10 meters, 33 feet, long, and bipedal. Despite all the exploration in the Morrison formation, it wasn’t until 1971 that the first Torvosaurus specimens were found in Colorado. The Portuguese specimens, discovered in 2000, have just this year been described as the second species within the genus Torvosaurus. The differences with the Morrison species are not huge, and the species are differentiated on the basis of the number of teeth and the shape of the mouth.

The Portuguese rocks have also yielded eggs and embryos that are ascribed to Torvosaurus. The specimens are the oldest theropod dinosaur eggs with a single layer to the shell.

The Portuguese specimen is the largest land carnivore known in Europe, and among the largest Jurassic carnivores anywhere. Other carnivores shared its ecosystem, including Allosaurus and Ceratosaurus.

—Richard I. Gibson

LINKS:
Largest predator in Europe 
Torvosaurus 

Lourinhã Formation 

Torvosaurus in Museum of Ancient Life at Thanksgiving Point in Lehi, Utah, U.S.A. Photo by leon7 used under Creative Commons license