The region of South America is known for having cave systems which have become popular with tourists from various parts of the world. Aside from their popularity as tourist destinations, the caves and caverns in the region also act as biological reserves. Recently, geologists discovered huge cave networks along the forests, believed to be more than just simple caves.
Huge Cave Networks Reveal Peculiar Marks
A peculiar cave in the state of Rondonia in northwest Brazil was investigated by the Brazilian Geological Survey in 2010. More than 1,500 known paleoburrows have been discovered in Brazil's southern and southeastern regions, which are classified into two types. The smaller burrows reach up to 1.5 meters in diameter, while the bigger ones are up to 2 meters high and 4 meters wide.
Similar colossal burrows, or paleoburrow, have been discovered in South America. The tunnels are very large, neatly constructed, and rank as the largest known paleoburrow in the Amazon region. It is twice the size of the second-largest paleoburrow located in Brazil.
The huge cave networks are estimated at least 8,000 to 10,000 years old, and any geologic process cannot explain their existence. According to researchers, no natural process can produce long tunnels that branch, rise, and fall with a circular or elliptical cross-section. The researchers have known the tunnels since the 1930s, but they were initially considered archaeological structures like the remains of caves carved out by ancient people.
Researchers got their first big clue about the origin of the huge cave networks from the ceiling and inner walls. Strange grooves were discovered in the granite, basalt, and sandstone surfaces, initially identified as the claw marks of a very large, ancient giant. The massive claw marks along the walls and ceilings suggest that the paleoburrows were made by extinct species of ancient giant ground sloth.
Most of the grooves are long and shallow and parallel to each other, probably produced by two or three claws of ancient giants. The marks are also smooth, although irregular ones are made by broken claws.
This finding seems to answer the mystery in paleontology about the burrows of ancient megafauna believed to have existed during the Pleistocene epoch. The size of the burrows and the claw marks in the walls are consistent with the size of giant ground sloths and giant armadillos.
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What Caused the Megafauna Extinction?
Megafauna are huge animals that once roamed the Earth during the Pleistocene era. It was believed that the landscape of South America contained ancient giants during this period in history, around 2.5 million to 11,700 years ago.
The extinction of megafauna occurred in many parts of the world, such as the Americas, Australia, and Madagascar. Among these regions, South America has the largest megafauna extinctions at the end of the Pleistocene era. The mystery surrounding the extinction of megafauna is still not yet resolved.
It was believed that the megafauna got extinct due to environmental and ecological conditions. Scientists predicted that megafauna existed in response to glacial conditions and got extinct when the Earth experienced warmer temperatures.
RELATED ARTICLE: Megafaunal Extinction During Ice Age Caused By Too Much Moisture, Study Suggests
Check out more news and information on Megafauna in Science Times.
