Mini T-Rex and chubby lizard discovered by palaeontologists

27 Aug 2015

Artist's conception of the newly discovered Gueragama sulamericana (Illustration: Julius Csotonyi)

A recent chance discovery in Wales by a palaeontology student produced the foot of a mini T-Rex, which stood half a metre tall 200 million years ago, while Canadian researchers have found the ‘missing link’ of lizard history.

Sam Davies was checking out the site of a cliff fall in Lavernock Beach, where the fossils of a dinosaur were discovered a year ago, with one foot missing.

The young student’s discovery, though, changes that.

“It was pure luck that I found it. It was just sitting on top of a slab of rock,” said Davies.

Graphic of the unnamed dinosaur discovery, via National Museum Cardiff

Graphic of the  discovery, via National Museum Cardiff

The little terror would have lived around 200m years ago, with incredibly sharp teeth, and was found at Jurassic cliffs that are known to be fossil-heavy.

“It was obvious the fossil was fingers or toes, because there were three in a row, but the first thing that came to mind was that it was some sort of plesiosaur,” said Davies.

The foot belongs to a dinosaur discovered a year ago at the same spot, coincidentally now on display at the National Museum in Cardiff.

Move over dinosaur

Meanwhile, Canadian palaeontologists have found fossils of an entirely new species of lizard, called the Gueragama sulamericana in Brazil.

The 80m-year-old fossils could be the missing link between Old World and New World lizards, according to Michael Caldwell, biological sciences professor at the University of Alberta.

“The roughly 1,700 species of iguanas are almost without exception restricted to the New World, primarily the southern United States down to the tip of South America,” said Caldwell.

What’s odd is chameleons and bearded dragons, close relatives of iguanas, are exclusive to the Old World.

This could mean that the remains are from a time when the southern end of the great continent Pangea was still all one continent, with the subsequent breaking off then separating these species.

A floating Noah’s Ark

“South America remained isolated until about five million years ago. That’s when it bumps into North America, and we see this exchange of organisms north and south,” explained Caldwell.

“It was kind of like a floating Noah’s Ark for a very long time, about 100 million years. This is an Old World lizard in the New World at a time when we weren’t expecting to find it. It answers a few questions about iguanid lizards and their origin.”

Caldwell’s references to Noah’s Ark and his use of ‘missing link’ terminology, however, don’t cut it for some, with a response to his findings criticising his “very fascinating findings” that are “muddled by poor communication” in the summary “at the public interface”.

The study is published in Nature.

Gordon Hunt was a journalist with Silicon Republic