Dinosaur Lineage Traced to Africa, Page 2

//

Before the extinction event, 35 percent of four-legged species were found in the majority of the areas studied, with some species having ranges that stretched 1600 miles. Ten million years after the die-off, just 7 percent of species were found in the same number of areas.

In addition to the already mentioned animals, the survivors included other archosaurs, which is a group that includes modern crocodiles, modern birds and- back in the day- dinosaurs. Cynodonts also lived through the onslaught. This group later evolved into mammals, so these were our very distant ancestors. Certain additional reptiles and amphibians survived too.

While the fossil discoveries would seem to suggest that the motherland for dinosaurs was Africa, the researchers point out that landmasses were configured very differently then. What is now Africa was part of Gondwanaland, the southern portion of Pangea.

PHOTOS: Oldest Dinosaur Nursery Found

Co-author and geologist Sterling Nesbitt of the Field Museum of Natural History explained to Discovery News that "true dinosaurs first show up about 230 million years ago from what is now Argentina. We think that dinosaurs first evolved in Gondwanaland-including Africa, South America, India, Madagascar, Australia, Antarctica."

Bruce Rubidge, a dinosaur specialist at the University of Witwatersrand, said, "The expeditions by this team of researchers to little-explored Permian and Triassic aged depositional basins in Africa and Antarctica, which form part of the supercontinent Gondwana, has greatly enhanced our understanding of the distribution of land-living vertebrates that lived more than 200 million years ago."

Rubidge continued, "The results of this research provide documentation of distribution, both in time and space, of important land living vertebrates soon after the greatest extinction event of all times and indicate how the post extinction recovery fauna evolved and became distributed around the world."

The study could serve as a warning to us, since humans are now contributing to yet another mass extinction event. The Triassic animals were only just starting to recover 8 million years after the huge die-off.

"Eight million years is a long time to wait," said Angielczyk. "If we value the communities of organisms around us, conserving and protecting them is the main way we can ensure they will persist."