BRAZIL: Fossil find has South African links

A fossil of a herbivorous 'reptile' found recently in Brazil has close links to a species discovered at Williston in South Africa's Northern Cape province in 1999. The latest find indicates how the South American and African continents were once part of Gondwana, the southernmost of the two supercontinents.

The South African animal was discovered by a team from the Bernard Price Institute for Palaeontology at the University of the Witwatersrand (Wits) while a former Wits student, Dr Juan Cisneros, discovered and named the Brazilian animal with two colleagues, together with Professor Bruce Rubidge, Director of the institute.

The new find, along with the specimen from Williston, is the oldest evidence of similar land-living vertebrates that once lived on what are now the African and South American continents. The scientists say this shows that more than 260 million years ago, the animals were moving between today's two separate and distant continents.

The new Brazilian animal is remarkable because it has extraordinarily long sabre canines. The researchers say this reflects the oldest evidence of combat behaviour in a herbivorous 'reptile' and is also the oldest record of dental occlusion in the evolutionary lineage leading toward mammals.

Tiarajudens eccentricus is a 260-million year old herbivorous basal anomodont. Its closest relative is Anomocephalus africanus, the species found at Williston. The two species form a previously unknown group that lived in what was then Gondwanaland.

"This provides additional evidence of geographic contact between terrestrial faunas from these now separate continents; but, more importantly, it also establishes a temporal bridge," Rubridge said. "These animals represent nearly similar ages on both continents."

The new Brazilian species has unexpected dental features, as well as being the oldest known herbivore with saber canines. This indicates the animals used the large tooth for display against predators and also intra-specifically.

The new species also has a battery of teeth following the canine that are placed in bones from the palate and show evidence of dental occlusion with teeth from the lower jaw.

A report on the find was published last month in Science.