Baryonyx turns 21 this Year

Baryonyx the unusual theropod dinosaur turns 21 years old this year.  The first remains of this dinosaur were uncovered in 1983, but it was formerly named and described in 1987, happy birthday Baryonyx!

Baryonyx was a bizarre carnivorous dinosaur, its discovery led many scientists to reconsider some of their assumptions regarding the habits of large, meat-eating dinosaurs.  Baryonyx may have been an ancestor of Spinosaurus.  The baryonchids had large, elongated skulls resembling that of a crocodile, strong forelimbs and a huge, curved thumb claw up to 30 centimetres long.  First described from the Weald clay (Barremian faunal stage) of Smokejacks, Brickworks clay pit located at Wallis Wood, near Ockley, Surrey in southern England, further remains have been discovered on the Isle of Wight and Spain.  There is also evidence that baryonchids lived in Africa.

Happy Birthday Baryonyx

Anatomical features indicate that Baryonyx may have been an ancestor of Spinosaurus aegyptiacus, however, making direct comparison with the fossils of this spinosaur are not possible as the most complete material was destroyed in a bombing raid on Germany during World War II.  The claw was the first part of the fossil to be discovered, amateur palaeontologist William Walker made the discovery.   A team was despatched from the Natural History museum in London and an excavation began which led to the recovery of about 70% of the skeleton.

An Illustration of Baryonyx

Picture credit: Everything Dinosaur

For a scale model of Baryonyx and other dinosaurs: Dinosaur and Prehistoric Animal Models.

Baryonyx was named and described by British palaeontologists Angela Milner and Alan Charig.  Further study of the fossils have led to speculation that Baryonyx may have had a humped back appearance, one thing is for certain, Baryonyx spp. had a remarkably high number of teeth in the jaws, more than in a typical tyrannosaur for example.  The teeth are gently curving and finely serrated (Spinosauridae teeth tend to be conical in shape and lack the fine serrations in contrast), this suggests that these animals were fish eaters.

A Dinosaur that Ate Fish

Numerous teeth in the jaws are characteristic of animals that catch slippery fish and the shape of the snout, superficially resembling fish eating crocodiles adds credence to this theory regarding the diet of baryonchids.  The presence of partially digested fish scales in the stomach region of the Wallis Wood specimen supports this fish-eating theory.  There would have been plenty of fish about in the area where the first Baryonyx specimen was found, the palaeoenvironmental evidence indicates that it was a wide floodplain dotted with lakes and meandering rivers.

However, remains of a small iguanodontid was also found so perhaps Baryonyx was a general predator happy to eat what it could catch.

The “fishing” dinosaur theory has certainly grabbed the imaginations of a number of scientists.   Many have speculated that whilst hunting for fish baryonchids may have waded or swam in the water or perhaps hunted for fish using stealth as modern herons and egrets do.  A number of eminent writers Buffetaut (1989) for example have suggested that members of the Spinosauridae were amphibious whilst other scientists, notably Bakker (1992) has commented that these creatures could have been slowly evolving a more aquatic lifestyle, becoming more adapted to a marine environment analogous to the Palaeogene placental mammal Ambulocetus which is believed to be an early ancestor of modern whales.