Oldest Fossil of Modern African Venomous Snake Unearthed in Tanzania
Scientists have discovered what may be the fossilized evidence of a venomous snake in Africa that existed some 25 million years ago, according to a new finding.
Ohio University scientists have unearthed the oldest fossil evidence of modern venomous snake in Africa that existed as early as 25 million years ago. This fossil is strong evidence that elapid snakes that include cobras, kraits and sea snakes were present in Africa.
Elapids are the larger group of snakes known as colubroids and are active foragers and are known to use an array of techniques to capture their prey. Some of these methods involve the use of venom. Also colubroid fossils were found dating some 50 million years ago and researchers did not expect them to dominate the environment 25 million years ago.
"In the Oligocene epoch, from about 34 to 23 million years ago, we would have expected to see a fauna dominated by booid snakes, such as boas and pythons. These are generally 'sit and wait' constricting predators that hide and ambush passing prey," lead author Jacob McCartney, a postdoctoral researcher in the Ohio University Heritage College of Osteopathic Medicine, said in a news release.
The newly discovered species is named 'Rukwabyoka holmani' and was unearthed in the Rukwa Rift Basin of Tanzania. The species genus name comes from the Rukawa region with the Swahili word for snake. And the species name honors J.Alan Holman, a palaeontologist. The team found eight different types of fossil snakes varying in length from 2.6 mm to 5 mm.
The team initially believed that the fauna in the region was mainly dominated by the booids but was surprised to see that there were more colubroids than booids. This suggests that the environment became more open and seasonally dry during early times in Africa, which favored snakes that indulge in active foraging activities that do not require them to hide and ambush prey.
"This finding gives further strength to the idea that tectonic activity in the East African Rift has helped to shape animal habitats in fascinating ways," said Nancy Stevens, an associate professor of biomedical sciences at Ohio University and co-author of the study. "The fossils suggest a fundamental shift toward more active and potentially venomous snakes that could exert very different pressures on the local fauna."
The researchers claim that further excavation program in other locations will indicate whether colubroid snakes dominated all of Africa during the Olugocene or just in the local region around the Rukwa Rift.
This finding was documented in the journal PLOS ONE.