Image: 'Dinosaur Island'
Dr. Steve Sweetman
Shown are drawings of some of the prehistoric species whose fossils have recently been found at the Isle of Wight.
By
updated 2/12/2009 12:34:55 PM ET 2009-02-12T17:34:55

In just four years, the Isle of Wight, otherwise known as "Dinosaur Island," has yielded the remains of 48 new animal species, including eight new dinosaurs, six dino-era mammals, and many different types of lizards, frogs and salamanders.

Together, the finds shed light on what life was like when dinosaurs dominated the planet.

All of the fossils were discovered by a resident of the island, Steve Sweetman, who is a research associate with the School of Earth and Environmental Sciences at the University of Portsmouth. His latest paper, which has been accepted for publication in the journal Acta Palaeontologica Polonica, concerns one of his rarest finds -- the remains of a mammal that scurried around on the dinosaur-trampled ground.

"This new species, as is often the case with fossil mammals, is known only from isolated teeth," Sweetman told Discovery News.

"It is of interest not just because it is something new, but because it is a new species of a genus (Eobaatar) that is otherwise known from rocks of roughly the same age occurring in Spain and slightly younger deposits in the Gobi Desert of Mongolia," he added.

He said this mammal, as for most others from the Mesozoic Era, was "very small, shrew or mouse-like and probably insectivorous." Certain others were slightly bigger, "say, rat-sized, and probably filled niches now occupied by rodents."

Of Sweetman's dinosaur discoveries, perhaps the most dramatic was a velociraptorine dromaeosaur, which appears to have been much larger than Velociraptor, a feathered carnivore whose popularity has risen in recent years since the theropod was featured in the movie "Jurassic Park."

Sweetman credits his record-breaking number of prehistoric animal finds with both his search technique and the site itself. For the former, instead of relying upon fossils exposed naturally by weather and waves, he digs up mud, which he transports to a makeshift local laboratory for fine sifting and microscopic analysis.

"In the very first sample I found a tiny jaw of an extinct, newt-sized, salamander-like amphibian and then new species just came coming," he said.

During the Cretaceous and Jurassic periods, the Isle of Wight was part of an island archipelago with landmasses connected by natural bridges at various points in time. The dinosaur-bearing rocks suggest the prehistoric animals thrived near a large river surrounded by coniferous forest.

The land of today's Isle of Wight was once much further south than it is today, with warmer, seasonal temperatures and plenty of rainfall. Sweetman, however, has found geological evidence suggesting that, as in many forests today, blazing fires would sometimes sweep through the region, leaving behind charred animal remains. Floods also appear to have been frequent.

But it was this "chaotic mixture" of events that led to decomposition of plant material contained in the island sediments that took oxygen out of the system, "a major factor in favor of the preservation of bones."

David Martill, a University of Portsmouth dinosaur authority who has also conducted research on the Isle of Wight, said, "Steve has become internationally recognized as a leading expert in his field and has many more exciting discoveries yet to be announced. He has already discovered 48 new species and he hasn't even started on the fish."

Although Sweetman has authored some journal papers documenting his discoveries, he still has many more to write, a project he is tackling now.

"However," he said, "I am still sieving samples and new things keep turning up, so this is probably enough of a project to keep me busy for the foreseeable future."

More on  dinosaurs archaeology

© 2012 Discovery Channel

Discuss:

Discussion comments

,

Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments