Living stromatolites found in a cattle trough, proving these ancient structures can form in completely unexpected environments. Life finds a way even in a watering hole.
An unexpected discovery
At Curtin Springs, a million-acre cattle station in the arid center of Australia, a routine check of a water trough led to a surprising scientific find. Submerged in the metal container were living stromatolites, structures nearly identical to the earliest fossil evidence of life on Earth.
Stromatolites are layered, rock-like mounds formed by colonies of microbes, primarily cyanobacteria. These organisms trap and bind sediment or precipitate minerals, slowly building up layers over time. Fossilized stromatolites found in Western Australia's Pilbara region are among the oldest, dating back approximately 3.5 billion years. For billions of years, these microbes were the dominant life form, and their photosynthesis is responsible for releasing the oxygen that transformed Earth's atmosphere and allowed other life to evolve.
Today, living stromatolites are rare. They survive mostly in extreme environments with few predators or competitors, such as the hypersaline waters of Hamelin Pool in Shark Bay, Western Australia. Finding them thriving in the freshwater of a cattle trough, an entirely artificial environment, demonstrated a new context for their formation.
The science of the trough
The water that feeds the trough at Curtin Springs is essential for the stromatolites' existence. It is pumped from an underground bore that taps into a mineral-rich aquifer. The water is high in calcium carbonate and magnesium sulphate, which discourages cattle from drinking excessively but provides the perfect building blocks for the cyanobacteria.
The microbes on the surface of the structures use photosynthesis for energy. This process alters the water chemistry around them, causing dissolved minerals to precipitate and cement the layers of the growing mound. This mechanism links directly to the processes that formed the ancient fossils. The discovery shows that the specific water chemistry, rather than a saline marine environment, is essential for stromatolite growth. It also suggests that similar structures might be found in other freshwater springs and bores where the conditions are right. The find expands our understanding of where these living fossils can exist and provides a readily accessible, modern example of a process that shaped the entire planet.
💡Fun Facts
Stromatolites are sometimes called "living fossils" because modern examples are built by the same type of microbes that created fossils billions of years ago.
The photosynthesis performed by ancient stromatolite-building cyanobacteria produced the oxygen in our atmosphere, which built up to its current level of 21% over eons.
Before the discovery of living stromatolites in 1956, scientists were uncertain about how the fossilized structures had originally formed.
Today, the main locations to see large colonies of living marine stromatolites are Hamelin Pool in Western Australia and the Bahamas.
The Curtin Springs Wayside Inn store and reception are open from 7 am until late daily. Access to the specific stromatolite site may be by inquiry or guided tour.
Admission
Viewing is arranged through the station; some tours and experiences have associated costs.
Accessibility
The terrain is typical of an outback cattle station, with unpaved ground.