Around 18,000 years earlier, glacial epoch individuals in what is now Ukraine most likely weathered the incredibly severe environment by constructing parts of their shelters out of massive bones, a brand-new research study discovers.

The massive houses demonstrate how neighborhoods grew in severe environments, turning the residues of huge animals into protective architecture,” the archaeologists wrote in a statement.

To investigate these questions, archaeologists re-examined the site to try and get a better idea of when it was built and how long it stayed in use. They dated the remains of about a dozen small animals found near the mammoth dwellings to try and get a more precise chronology.

The largest structure at Mezhyrich dates to 18,323 to 17,839 years ago, the team reported in the study, published on Nov. 21 on the publishing platform Open Research Europe. These dates are just after the Last Glacial Maximum (26,500 to 19,000 years ago), the coldest part of the last ice age. The researchers noted that the dwelling may have been used for up to 429 years. This indicates that the “shelters were useful options for survival instead of long-term settlements,” they wrote in the statement.

The structure of the shelters might have had “mammoth skulls and large long bones, set vertically into the ground [which] formed a kind of plinth or ‘foundation,'” research study co-author Pavlo Shydlovskyian archaeology teacher at the Taras Shevchenko National University of Kyiv, informed Live Science in an e-mail.

A wood structure might have covered parts of the shelter, together with hides from smaller sized animals or perhaps birch bark. In addition, “tusks and large flat bones were placed on the upper part of the structure [the roof] functioning as weights and wind protection,” Shydlovskyi stated.