The call of nature has led an Australian man to find the oldest-known evidence of an Aboriginal settlement in existence.
Adnyamathanha elder Clifford Coulthard and a consultant archaeologist and doctoral student, Giles Hamm, were surveying in the outback when Mr Coulthard needed to go to the bathroom.
"A man getting out of the car to go to the toilet led to the discovery of one of the most important sites in Australian prehistory," Mr Hamm told ABC.
"Nature called and Cliff walked up this creek bed into this gorge and found this amazing spring surrounded by rock art."
The rock shelter contained ancient artefacts, tools, and bones from a giant wombat-like marsupial called Diprotodon optatum, placing human settlement in the area back at least 49,000 years.
This is 10,000 years older than previously believed. The new timeframe overlaps human settlement with the existence of Australian megafauna - large animals.
Professor and report co-author Gavin Prideaux of Flinders University, a megafauna expert, told reporters the study was an important breakthrough in the argument over whether humans or climate change led to megafauna dying out.
"The only way those bones and shells got there [because of the steep incline up to the rock shelter] is because people brought them there [to eat] ... in terms of megafauna that's the really significant finding," he said.
"The find undermines one of the supposed pillars of support for climate change, not humans, causing the extinctions because the site shows humans lived alongside these animals and hunted them."