The fragmented femur appears to originate from a scary-looking carnivorous dinosaur, paleontologists say

May 21, 2015 09:11 GMT  ·  By
Fossilized femur found in Washington, US, appears to originate from a theropod
2 photos
   Fossilized femur found in Washington, US, appears to originate from a theropod

A report published in the science journal PLOS ONE earlier this week announces the discovery of a dinosaur thigh bone in the state of Washington in the US. The find is a first for the state in that the fragmented femur is the only dinosaur fossil thus far uncovered in this corner of the world. 

The fossilized dinosaur remain, pictured below, was pulled from a marine rock in the San Juan Islands, an archipelago located between the US mainland and Canada's Vancouver Island.

The researchers who found it were exploring the area in search not of dinosaur bones but of ancient marine invertebrates, maybe even a few other fossilized remains. Since finding dinosaur fossils was not on their agenda, they were understandably surprised when they stumbled upon the femur.

The thigh bone appears to belong to a predatory dinosaur

As mentioned, the dinosaur femur was embedded in a marine rock at the time when it was discovered in April 2012. Later that year, in May, Burke Museum paleontologists managed to excavate it.

In their paper in the journal PLOS ONE, the researchers explain that, having analyzed the fragmented dinosaur thigh bone, they found it to be about 80 million years old.

As for its origin, the scientists say that the femur appears to come from a predatory dinosaur belonging to a group of ancient beasts known as theropods. The infamous T. rex was one of the proud members of this group.  

“The fossil is a partial left femur of a theropod dinosaur, the group of two-legged, carnivorous dinosaurs that includes Velociraptor, Tyrannosaurus rex and modern birds,” they detail.

Since the femur isn't in very good shape - it's basically a fragmented fossil measuring merely 16.7 inches (47.4 centimeters) in length and 8.7 (22 centimeters) inches in width - specialists cannot identify its exact species.

How come no other dinosaur bones have been found in Washington?

Fossilized remains of dinosaurs have until now been unearthed in 37 US states, with Washington being the last to join the party. Of the dinosaur bones included in the US' collection, the majority are 240 million to 66 million years old.

During this time in our planet's history, the region that is now the state of Washington was submerged in the nearby ocean and only had very little exposed rock to show. Since most dinosaurs were land creatures, there weren't all that many such beasts roaming around in ancient Washington.

This explains why just this one dinosaur bone has so far been discovered in the state and why the fossil was found not on land but embedded in a marine rock in the San Juan Islands archipelago.

The fossil is a portion of a femur leg bone
The fossil is a portion of a femur leg bone

Photo Gallery (2 Images)

Fossilized femur found in Washington, US, appears to originate from a theropod
The fossil is a portion of a femur leg bone
Open gallery