Across northern South America , at that topographic point are hundreds of colossal tunnels large plenty for humans to walk through , but they weren’t dug past times men. Nor they were formed past times whatever known geological process. But their creators accept left testify all closed to the walls as well as ceilings—giant hook marks.
Geologists telephone phone these tunnels “paleoburrow ,” as well as they are believed to accept been dug past times an extinct species of giant Blue Planet sloth.
A large paleoburrow inwards Brazil. Photo credit: Heinrich Frank
The term was coined past times Heinrich Frank , a professor at the Federal University of Rio Grande practise Sul , inwards Brazil , who chanced upon 1 at a structure site inwards the town of Novo Hamburgo , inwards the early on 2000s. Up until thence , picayune was known or written close these tunnels inwards scientific literature. But since he came upon his showtime , Heinrich Frank as well as other researchers accept discovered to a greater extent than than 1 ,500 tunnels , inwards the solid soil of Rio Grande practise Sul alone. Some of these burrows stair out hundreds of feet long as well as branched off into several direction.
The largest 1 measured 2 ,000 feet long , half dozen feet tall as well as iii to v feet wide. An estimated iv ,000 metric tons of dirt as well as stone were dug out of the hillside to practise the burrow. It was champaign the run of non 1 or 2 individuals but several generations.
Frank believes the burrows were dug past times a genus of giant Blue Planet sloths , every bit large every bit modern elephants , that 1 time lived inwards South America until close 10 ,000 years ago. They were some of the biggest solid soil mammals on populace exceeded inwards size only past times the mammoth. Others believe that extinct armadillos , which were smaller than the giant sloths , were responsible for the burrows.
Claw marks on the sides of the burrow. Photo credit: Heinrich Frank
Regardless of who dug them , the sheer size of the burrows is something that Frank as well as his colleagues are silent trying to explain.
The paleoburrows too accept a foreign geographic distribution. They accept been establish only inwards the southern Brazilian states of Rio Grande practise Sul as well as Santa Catarina. Very few accept been establish inwards northern Brazil , or inwards other South American countries. Even inwards North America , where the giant Blue Planet sloths as well as giant armadillos 1 time lived , no paleoburrows accept been found.
Greg McDonald , a paleontologist from the Bureau of Land Management , yet , believes that it’s exactly a affair of fourth dimension earlier nosotros detect them.
“The fact that nosotros don’t accept them hither could but hold upward that we’ve overlooked them ,” he says.
There are silent a lot of unanswered questions surrounding the paleoburrows as well as its creators. Who built them? Why they were built? How they were built , as well as when?
Inside the showtime paleoburrow discovered inwards the Amazon. It’s nearly twice every bit large every bit the second-largest known burrow , located elsewhere inwards Brazil. Photo Credit: Amilcar Adamy/CPRM
A closer await at those hook marks. Photo credit: Heinrich Frank
Outside the entrance to a paleoburrow. Photo credit: Heinrich Frank
Megatherium americanum , the giant sloth.
Source: Discover Magazine